Re: [Emc-users] 240V single phase input vfd

[Jon Elson]

On 01/03/2018 12:18 PM, Dave Cole wrote:
Did you have to put a choke or filter on the incoming 
power to mimimize EMI ??


I had to put a line filter box on the input to one of my 
VFDs.  It caused "hash" on my computer screen.


Jon

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Re: [Emc-users] 240V single phase input vfd

[andy pugh]

On 3 January 2018 at 22:05, Dave Cole  wrote:

> Andy, do you have a real Huan Yang drive with the braking circuitry or do
> you have a clone of a Huan Yang?

I don't know how you can tell for sure, but mine was sold as a real
HY, and does have the braking connectors.
I haven't bothered to fit one, my lathe has a spindle brake.

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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

Looking on Ebay there are some drives clearly marked Huan Yang on the 
pictures and then there are other drives that are not marked that appear 
identical in the pictures yet they are quite a bit cheaper.


Andy, do you have a real Huan Yang drive with the braking circuitry or 
do you have a clone of a Huan Yang?


Dave

On 1/3/2018 2:29 PM, Eric Keller wrote:

On Tue, Jan 2, 2018 at 10:26 AM, Eric Keller  wrote:


The Huan Yang line of VFDs sold on ebay feature a 4kw version that will
run off of single phase.  The only problem with them is lack of braking on
some models.  The Mach crew have figured out the modbus connections. About
$200.


I'm told that the HY vfd's that don't have provision for braking are the
counterfeits, according to someone on CNCzone.  I believe it, there is a
pretty big difference in quality in the boards people have posted pictures
of online.
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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Wednesday 03 January 2018 11:03:05 Dave Cole wrote:

> Some of the "Driveswarehouse" type places sell solid state "phase
> converters" that have no speed control, but they seem to cost as much
> or more than the equivalent sized VFD.    No idea why.   It must be
> driven by the marketplace.
> I suppose if all you are driving is a blower or pump then having
> onboard braking circuitry might be close to worthless.
> The Estop requirements on most automation machinery requires a rapid
> stop on all rotating machinery.
> So... is anyone going to buy the $125 5 hp drive and let us know how
> long it lasts before the drive goes "pop".  ;-)
>
> Dave

Well, so far and definite not in a production environment as I cut lots 
of air before making swarf, my cheap, break resistorless clone, has 
managed to protect itself from everything I throw at it, and I have a 
g33.1 peck cycle test run that never finishes, I use it to tune the bits 
and pieces of the vfd for the fastest reversal at the end of the 
instroke, or at the other reversal at the end of the outstroke, and have 
succeeded in getting it down to just over 3 turns of the 3 jaw chuck at 
the bottom of the hole at 300 rpms. Correspondingly slower with the 8" 4 
jaw mounted. If the hole is blind, I'll convert the encoder counts shown 
by my hal code capture into turns, then from that inches or mm's, and 
edit the code to shorten the instroke by that amount. A ready source of 
quality blind taps is a plus, most of mine aren't.

Quickness of turnaround is a balancing act of how fast you can actively 
slow it without an overvoltage trip with that sensitivity riseing 
quickly with the rpms, and how long you leave the dc braking on and at 
what amperage. This latter is in time and amps so if you turn that up, 
but are only turning 75 rpm, you waste a lot of time at a slowly oozing 
stop before it actually begins the accel in the other direction. Some 
what of a damned if you do, and damned if you don't.

I get the impression that if this one had the rs485 port mentioned in the 
manual, but there are no places called out on its logic board to even 
connect one, that this type of thing could be done much more 
intelligently by the driver while it was actually running the motor by 
customizing all this to the rpms being turned. This could convert the 
reversal into a stanza of code at least as complex as a tool changer 
robot driver, but quicker than it can do now when one must negotiate 
your way thru the pushbuttons on the panel to change anything in what 
IMO, should be totally under linuxcnc's control, but the best I've got 
is a Spin-X1, no rs485.

I have a corcom brick wall filter to keep its noise from bothering the 
other line powered stuff, on the line side of the vfd. On this machine, 
linuxcnc is the motor power control thru some 40 amp SSR's. Works well 
and theres no huge and clunky drum switches in sight. The 7i90, thru the 
7i42TA's, has no problem controlling the SSR's.

Given that I'm not dealing with a 5hp motor, this $130 1.5 hp rated 
single phase 254 volt src vfd, running an elderly 1 hp 3 phase 230 rated 
motor, is giving me good value for the money. It is, considering the 
difficulty of the job, getting the job done. I bought two of these 
motors off an air compressor, retired after after 40 years without much 
weather protection during a remodel at the local horsepistol. $50 bucks 
for the pair, and 4 new bearings, only 2 have been used, so I have one 
in the bottom of the Sheldon, and a ready to roll spare in case for 
about $75 bucks.  Whats not to like?

Would I buy another if I had a need? Paypal just works.


> On 1/2/2018 6:35 PM, Gregg Eshelman via Emc-users wrote:
> > I run the VFD (that's never varied) on my old Monarch lathe without
> > using braking. It has terminals to connect a braking resistor but
> > for this machine there's no need.
> >
> > What I find crazy is that a simple, single function device that only
> > converts single phase to three phase, without all the fancy features
> > of a VFD, costs so much more than a VFD. When a 3HP VFD for
> > 220~240VAC input can be had for under $300, why isn't a version that
> > does absolutely nothing, no adjustments, no variation, no
> > programmability, but do the phase conversion not cost well under
> > $200 instead of a whole lot more? If some company produced a box
> > that was just a phase converter with an on/off button and terminals
> > for a remote switch as the only 'extras', and put a $199.99 price on
> > it, they'd be hard pressed to keep up with demand.
> >
> >  On Tuesday, January 2, 2018, 9:33:50 AM MST, Dave Cole
> >  wrote:
> >
> >   So what exactly do they do when the bus voltage rises during decel
> > ?? Or is there no decel control at all?
> > I've never seen a drive without braking circuitry and DC bus voltage
> > control.
> > 
> >-- Check out the vibrant tech community on one of the worl

Re: [Emc-users] 240V single phase input vfd

[Eric Keller]

On Tue, Jan 2, 2018 at 10:26 AM, Eric Keller  wrote:

>
> The Huan Yang line of VFDs sold on ebay feature a 4kw version that will
> run off of single phase.  The only problem with them is lack of braking on
> some models.  The Mach crew have figured out the modbus connections. About
> $200.
>

I'm told that the HY vfd's that don't have provision for braking are the
counterfeits, according to someone on CNCzone.  I believe it, there is a
pretty big difference in quality in the boards people have posted pictures
of online.
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Re: [Emc-users] 240V single phase input vfd

[andy pugh]

On 3 January 2018 at 18:18, Dave Cole  wrote:
> Did you have to put a choke or filter on the incoming power to mimimize EMI

I have one, but didn't fit it, and have seen no problems.

> Any issues with that drive?

None so far.

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designed for the especial use of mechanical geniuses, daredevils and
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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

Did you have to put a choke or filter on the incoming power to mimimize 
EMI ??


That's a good reference!

Any issues with that drive?
Thanks,
Dave

On 1/3/2018 11:56 AM, andy pugh wrote:

On 3 January 2018 at 16:03, Dave Cole  wrote:


So... is anyone going to buy the $125 5 hp drive and let us know how long it
lasts before the drive goes "pop".  ;-)

I bought this one, a close relative:
https://www.ebay.co.uk/itm/252036183460

It's been fine since August 2016, according to the date of this blog post:
http://bodgesoc.blogspot.de/2016/08/holbrook08.html



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Re: [Emc-users] 240V single phase input vfd

[Cristian Bontas]

I have one that seems identical, 2.2 kW, since August 2015. Running 
flawlessly since then. Added a 50 ohm 300 W braking resistor (it really 
helps), and controlling it through modbus (the HY version of it, 
available in the standard LinuxCNC distro now) using an USB to RS 485 
adapter.
But cheaper, I got it off AliExpress for 314 USD for the package 
including 2.2 kW water cooled spindle + VFD + clamp + water pump + 13 
pieces ER 20 collets.


On 03.01.2018 18:56, andy pugh wrote:

On 3 January 2018 at 16:03, Dave Cole  wrote:


So... is anyone going to buy the $125 5 hp drive and let us know how long it
lasts before the drive goes "pop".  ;-)

I bought this one, a close relative:
https://www.ebay.co.uk/itm/252036183460

It's been fine since August 2016, according to the date of this blog post:
http://bodgesoc.blogspot.de/2016/08/holbrook08.html




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Re: [Emc-users] 240V single phase input vfd

[Jon Elson]

On 01/03/2018 10:03 AM, Dave Cole wrote:
Some of the "Driveswarehouse" type places sell solid state 
"phase converters" that have no speed control, but they 
seem to cost as much or more than the equivalent sized 
VFD.No idea why.   It must be driven by the marketplace.
Yup, in the basements of most of our buildings at work, 
there are RACKS of VFDs that run ventilators, circulator 
pumps and other stuff like that.  We probably have at least 
1000 units, all controlled by an energy management system.
Many establishments have the same.  So, the world is awash 
in VFDs, new and used.  These places all have 3-phase power, 
but are using the VFDs for energy conservation, mostly.  The 
market for devices to provide just a 3rd phase from 
single-phase power is much smaller.


Jon

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Re: [Emc-users] 240V single phase input vfd

[andy pugh]

On 3 January 2018 at 16:03, Dave Cole  wrote:

> So... is anyone going to buy the $125 5 hp drive and let us know how long it
> lasts before the drive goes "pop".  ;-)

I bought this one, a close relative:
https://www.ebay.co.uk/itm/252036183460

It's been fine since August 2016, according to the date of this blog post:
http://bodgesoc.blogspot.de/2016/08/holbrook08.html

-- 
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designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

Some of the "Driveswarehouse" type places sell solid state "phase 
converters" that have no speed control, but they seem to cost as much or 
more than the equivalent sized VFD.    No idea why.   It must be driven 
by the marketplace.
I suppose if all you are driving is a blower or pump then having onboard 
braking circuitry might be close to worthless.
The Estop requirements on most automation machinery requires a rapid 
stop on all rotating machinery.
So... is anyone going to buy the $125 5 hp drive and let us know how 
long it lasts before the drive goes "pop".  ;-)


Dave

On 1/2/2018 6:35 PM, Gregg Eshelman via Emc-users wrote:

I run the VFD (that's never varied) on my old Monarch lathe without using 
braking. It has terminals to connect a braking resistor but for this machine 
there's no need.
  
What I find crazy is that a simple, single function device that only converts single phase to three phase, without all the fancy features of a VFD, costs so much more than a VFD. When a 3HP VFD for 220~240VAC input can be had for under $300, why isn't a version that does absolutely nothing, no adjustments, no variation, no programmability, but do the phase conversion not cost well under $200 instead of a whole lot more?

If some company produced a box that was just a phase converter with an on/off 
button and terminals for a remote switch as the only 'extras', and put a 
$199.99 price on it, they'd be hard pressed to keep up with demand.

 On Tuesday, January 2, 2018, 9:33:50 AM MST, Dave Cole 
 wrote:
  
  So what exactly do they do when the bus voltage rises during decel ??

Or is there no decel control at all?
I've never seen a drive without braking circuitry and DC bus voltage
control.
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Re: [Emc-users] 240V single phase input vfd

[Gregg Eshelman via Emc-users]

They have to have some type of microprocessor, non-volatile storage, more than 
one switch/button, sometimes a rotary knob, some type of display too, even if 
it's just a pair of 7-segment LEDs. But they do all of that and sell it for 
LESS than the 'dumb' devices that are fixed function with nothing adjustable. 
 

On Wednesday, January 3, 2018, 2:42:37 AM MST, Les Newell 
 wrote:  
 
 Hi Gregg,

The complicated and expensive bit is in creating the 3-phase. Most of 
the other functions are simply software tweaks that in mass production 
add next to nothing to the cost of the drive.

Les

On 02/01/18 23:35, Gregg Eshelman via Emc-users wrote:
> I run the VFD (that's never varied) on my old Monarch lathe without using 
> braking. It has terminals to connect a braking resistor but for this machine 
> there's no need.
>  
> What I find crazy is that a simple, single function device that only converts 
> single phase to three phase, without all the fancy features of a VFD, costs 
> so much more than a VFD. When a 3HP VFD for 220~240VAC input can be had for 
> under $300, why isn't a version that does absolutely nothing, no adjustments, 
> no variation, no programmability, but do the phase conversion not cost well 
> under $200 instead of a whole lot more?
> If some company produced a box that was just a phase converter with an on/off 
> button and terminals for a remote switch as the only 'extras', and put a 
> $199.99 price on it, they'd be hard pressed to keep up with demand.
>
>      On Tuesday, January 2, 2018, 9:33:50 AM MST, Dave Cole 
> wrote:
>  
>  So what exactly do they do when the bus voltage rises during decel ??
> Or is there no decel control at all?
> I've never seen a drive without braking circuitry and DC bus voltage
> control.  
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Re: [Emc-users] 240V single phase input vfd

[Les Newell]

Hi Gregg,

The complicated and expensive bit is in creating the 3-phase. Most of 
the other functions are simply software tweaks that in mass production 
add next to nothing to the cost of the drive.


Les

On 02/01/18 23:35, Gregg Eshelman via Emc-users wrote:

I run the VFD (that's never varied) on my old Monarch lathe without using 
braking. It has terminals to connect a braking resistor but for this machine 
there's no need.
  
What I find crazy is that a simple, single function device that only converts single phase to three phase, without all the fancy features of a VFD, costs so much more than a VFD. When a 3HP VFD for 220~240VAC input can be had for under $300, why isn't a version that does absolutely nothing, no adjustments, no variation, no programmability, but do the phase conversion not cost well under $200 instead of a whole lot more?

If some company produced a box that was just a phase converter with an on/off 
button and terminals for a remote switch as the only 'extras', and put a 
$199.99 price on it, they'd be hard pressed to keep up with demand.

 On Tuesday, January 2, 2018, 9:33:50 AM MST, Dave Cole 
 wrote:
  
  So what exactly do they do when the bus voltage rises during decel ??

Or is there no decel control at all?
I've never seen a drive without braking circuitry and DC bus voltage
control.
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Re: [Emc-users] 240V single phase input vfd

[Peter Blodow]

Gregg,
the 5 Hz is because - at least hereabouts - the VFDs are used mostly for 
ventilation drives and they start with low speed and then accelerate for 
noise reasons. Maybe there are also safety reasons.

Peter

Am 03.01.2018 um 00:43 schrieb Gregg Eshelman via Emc-users:

The one I have on my old Monarch lathe, to start in higher speed gears I have 
to slip the clutch a bit or it'll quit with an overcurrent fault. In lower 
gears I can just pull the lever.
There may be some programmable adjustment that can fix that, but it works as 
it's setup now. One crazy thing was out of the box it was set to a frequency of 
5Hz instead of 60. I'm not worried about any possible negative effects on the 
1943 vintage 3 horsepower motor, I don't use it a lot. A newer motor with lower 
rotating mass might start easier.
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Re: [Emc-users] 240V single phase input vfd

[Gregg Eshelman via Emc-users]

The one I have on my old Monarch lathe, to start in higher speed gears I have 
to slip the clutch a bit or it'll quit with an overcurrent fault. In lower 
gears I can just pull the lever.
There may be some programmable adjustment that can fix that, but it works as 
it's setup now. One crazy thing was out of the box it was set to a frequency of 
5Hz instead of 60. I'm not worried about any possible negative effects on the 
1943 vintage 3 horsepower motor, I don't use it a lot. A newer motor with lower 
rotating mass might start easier.
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Re: [Emc-users] 240V single phase input vfd

[Gregg Eshelman via Emc-users]

I run the VFD (that's never varied) on my old Monarch lathe without using 
braking. It has terminals to connect a braking resistor but for this machine 
there's no need.
 
What I find crazy is that a simple, single function device that only converts 
single phase to three phase, without all the fancy features of a VFD, costs so 
much more than a VFD. When a 3HP VFD for 220~240VAC input can be had for under 
$300, why isn't a version that does absolutely nothing, no adjustments, no 
variation, no programmability, but do the phase conversion not cost well under 
$200 instead of a whole lot more?
If some company produced a box that was just a phase converter with an on/off 
button and terminals for a remote switch as the only 'extras', and put a 
$199.99 price on it, they'd be hard pressed to keep up with demand.

On Tuesday, January 2, 2018, 9:33:50 AM MST, Dave Cole 
 wrote:  
 
 So what exactly do they do when the bus voltage rises during decel ??  
Or is there no decel control at all?
I've never seen a drive without braking circuitry and DC bus voltage 
control.  
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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Tuesday 02 January 2018 12:50:24 Les Newell wrote:

> Hi Gene,
>
> Are you sure your drive isn't shutting down due to over voltage rather
> than over current? The only way to brake a 3 phase motor without
> pumping power back into the bus is to use DC braking. DC braking can
> cause rotor heating problems on machines that decelerate often.
>
This is true, so I've had to program currents for dc braking as well as 
for how long. The only place where I might cause a rotor overheat might 
be with a big tap it can't pull in one stroke and "pecking" the g33.1 
with an incremental depth. I've not tried a tap that big yet. Generally 
I've used a g76 for that as I have tools small enough to make a 1/2" 50 
tpi internal thread, which I had done several times but usually on TLM, 
which has a dc motor setup all the way. I need to make a tap holder to 
fit into an axa tool holder yet. That will likely not get done till I 
need it. :) When will I need it is the $64k question. :)
> Les
>
> On 02/01/2018 17:42, Gene Heskett wrote:
> > And they are full 4 quadrant controllers, so within reason no
> > braking R's are required. Laying on the table, I can reverse a 1hp 3
> > phase motor turning 2400 revs, fast enough to make it jump 3" up in
> > the air with one of those 1.5 horse rated, $128 on ebay controllers.
> > Installed on a lathe with an 8" chuck, I have to program it to take
> > a bit over a second to reverse that 8" chuck from 200 revs because I
> > have to set a limit of the decel current else it self protects with
> > a total shutdown. So I am a happy camper until I decide to put a 5
> > hp on my old Sheldon.  Can I do rigid tapping? Yup. I have hal code
> > to tell me how much overshoot occurs at the bottom of the hole, so I
> > don't break taps  hitting the bottom of a blind hole.
> >
> > Cheers, Gene Heskett
>
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Cheers, Gene Heskett
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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Tuesday 02 January 2018 11:07:19 John Figie wrote:

> That would be a poor design if no braking resistor causes it to blow
> up. Once the bus gets pushed up to its max limit it should let the
> motor coast to a stop.
>
Mine has no place to hook up a braking R at all, and that is exactly what 
mine does, coast to a stop when asked to do something faster than it can 
handle. Programing it properly, is a pain, but the defaults are way 
too "conservative" for real use.

> John Figie
>
> On Jan 2, 2018 9:58 AM, "Eric Keller"  wrote:
> > On Tue, Jan 2, 2018 at 10:46 AM, Les Newell
> > 
> >
> > wrote:
> > >  I would avoid the Huanyang drives as they have a reputation for
> > > blowing up.
> > >
> > > Les
> >
> > My thought is they probably blow up because they have no braking
> > circuitry installed, even internal to the drive. Unless it gets
> > added. The gohz seems to be the same hardware/firmware just from a
> > short scan of the manual. Wonder if it has a braking circuit.
> > 
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Cheers, Gene Heskett
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Re: [Emc-users] 240V single phase input vfd

[Les Newell]

Hi Gene,

Are you sure your drive isn't shutting down due to over voltage rather 
than over current? The only way to brake a 3 phase motor without pumping 
power back into the bus is to use DC braking. DC braking can cause rotor 
heating problems on machines that decelerate often.


Les

On 02/01/2018 17:42, Gene Heskett wrote:

And they are full 4 quadrant controllers, so within reason no braking R's
are required. Laying on the table, I can reverse a 1hp 3 phase motor
turning 2400 revs, fast enough to make it jump 3" up in the air with one
of those 1.5 horse rated, $128 on ebay controllers. Installed on a lathe
with an 8" chuck, I have to program it to take a bit over a second to
reverse that 8" chuck from 200 revs because I have to set a limit of the
decel current else it self protects with a total shutdown. So I am a
happy camper until I decide to put a 5 hp on my old Sheldon.  Can I do
rigid tapping? Yup. I have hal code to tell me how much overshoot occurs
at the bottom of the hole, so I don't break taps  hitting the bottom of
a blind hole.

Cheers, Gene Heskett




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Re: [Emc-users] 240V single phase input vfd

[Les Newell]

That seems expensive. The UK price I paid for mine was £220 + £9 
shipping + tax. It is very unusual for prices to be lower in the UK than 
the US.


They will deliver to the US. I checked the prices and delivery shouldn't 
be more than £50 for 2-3 day delivery. This makes the total around  
$367. I don't know if you would have to pay any duties or tax at your end.


Les

On 02/01/2018 16:26, Ken Strauss wrote:

See http://www.ebay.com/bhp/yaskawa-v1000 for eBay listings of Yaskawa V1000
drives. There is a new 5HP unit for us$499.50 with free shipping. I have no
knowledge of the seller...



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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Tuesday 02 January 2018 10:26:42 Eric Keller wrote:

> On Tue, Jan 2, 2018 at 9:04 AM, Dave Cole  
wrote:
> > Except that he needs a 5 hp single phase inverter.   Those are a
> > little harder to find and  a lot more expensive... near $1000 for
> > this AC Tech Drive.
>
> The Huan Yang line of VFDs sold on ebay feature a 4kw version that
> will run off of single phase.  The only problem with them is lack of
> braking on some models.  The Mach crew have figured out the modbus
> connections. About $200.

And they are full 4 quadrant controllers, so within reason no braking R's 
are required. Laying on the table, I can reverse a 1hp 3 phase motor 
turning 2400 revs, fast enough to make it jump 3" up in the air with one 
of those 1.5 horse rated, $128 on ebay controllers. Installed on a lathe 
with an 8" chuck, I have to program it to take a bit over a second to 
reverse that 8" chuck from 200 revs because I have to set a limit of the 
decel current else it self protects with a total shutdown. So I am a 
happy camper until I decide to put a 5 hp on my old Sheldon.  Can I do 
rigid tapping? Yup. I have hal code to tell me how much overshoot occurs 
at the bottom of the hole, so I don't break taps  hitting the bottom of 
a blind hole.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] 240V single phase input vfd

[John Figie]

If you have no braking resistor, or try to stop too fast for the resitor in
use as the DC bus get pumped up to its maximum then the drive should fault
and no longer control the motor.  If the motor is allowed to just coast it
will no longer pump up the bus.

There are some cases where what I said is not completely true and that
would be for some kind of permanent magnet ac motor running above its base
speed (field weakening mode) when even if the motor is coasting the back
EMF would then go too high.  But these special cases dont apply for our
simple case.  With an induction motor once the ac voltage is removed the
field will quickly decay.

John Figie

On Jan 2, 2018 10:28 AM, "Dave Cole"  wrote:

> So what exactly do they do when the bus voltage rises during decel ??  Or
> is there no decel control at all?
> I've never seen a drive without braking circuitry and DC bus voltage
> control.
>
> Dave
>
> On 1/2/2018 11:07 AM, John Figie wrote:
>
>> That would be a poor design if no braking resistor causes it to blow up.
>> Once the bus gets pushed up to its max limit it should let the motor coast
>> to a stop.
>>
>> John Figie
>>
>> On Jan 2, 2018 9:58 AM, "Eric Keller"  wrote:
>>
>> On Tue, Jan 2, 2018 at 10:46 AM, Les Newell 
>>> wrote:
>>>
>>>   I would avoid the Huanyang drives as they have a reputation for blowing
 up.

 Les



 My thought is they probably blow up because they have no braking
>>> circuitry
>>> installed, even internal to the drive. Unless it gets added. The gohz
>>> seems
>>> to be the same hardware/firmware just from a short scan of the manual.
>>> Wonder if it has a braking circuit.
>>> 
>>> --
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>>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] 240V single phase input vfd

[Eric Keller]

On Tue, Jan 2, 2018 at 11:29 AM, Dave Cole  wrote:

> So what exactly do they do when the bus voltage rises during decel ??  Or
> is there no decel control at all?
> I've never seen a drive without braking circuitry and DC bus voltage
> control.
>
> They do cut out when the bus voltage gets too high. I just expect there
needs to be something to reduce the dc bus, and they don't have anything.
The best theory I have seen is that these VFDs are built for continuous
duty, and braking is not their main concern.  The older ones had places to
easily put braking components, some newer ones deleted that from the
board.  So you never know what you are going to get if you buy one now.

I keep expecting a vendor to start selling ones with the braking circuits
installed, all that is missing is a few cheap parts.  But no joy on that.
I'm hoping mine is one of the ones where you can add the parts, but
probably not.
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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

So what exactly do they do when the bus voltage rises during decel ??  
Or is there no decel control at all?
I've never seen a drive without braking circuitry and DC bus voltage 
control.


Dave

On 1/2/2018 11:07 AM, John Figie wrote:

That would be a poor design if no braking resistor causes it to blow up.
Once the bus gets pushed up to its max limit it should let the motor coast
to a stop.

John Figie

On Jan 2, 2018 9:58 AM, "Eric Keller"  wrote:


On Tue, Jan 2, 2018 at 10:46 AM, Les Newell 
wrote:


  I would avoid the Huanyang drives as they have a reputation for blowing
up.

Les




My thought is they probably blow up because they have no braking circuitry
installed, even internal to the drive. Unless it gets added. The gohz seems
to be the same hardware/firmware just from a short scan of the manual.
Wonder if it has a braking circuit.

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Re: [Emc-users] 240V single phase input vfd

[Ken Strauss]

See http://www.ebay.com/bhp/yaskawa-v1000 for eBay listings of Yaskawa V1000
drives. There is a new 5HP unit for us$499.50 with free shipping. I have no
knowledge of the seller...

> -Original Message-
> From: Les Newell [mailto:les.new...@fastmail.co.uk]
> Sent: Tuesday, January 02, 2018 10:46 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] 240V single phase input vfd
>
> In the UK, inverterdrive.com have really reasonable prices. Probably not
too
> useful for you but this link shows all of their 240V single phase drives
> <https://inverterdrive.com/group/AC-Inverter-Drives-
> 230V/?filter=Power%7c4kW&filter=Input%7c230Vac+1ph>.
> You could see if other companies local to you stock any of those drives.
> Their Yaskawa V1000 drive is only a bit more than the gohz equivalent. I
don't
> know easily available Yaskawa drives are in the US. Yaskawa are a well
known
> and reliable brand.
>
>   I would avoid the Huanyang drives as they have a reputation for blowing
up.
>
> Les
>
>
>
> On 01/01/2018 00:45, John Figie wrote:
> > I have a 5 hp 240V 3 phase induction motor that is for a lathe
> > spindle.  I only have single phase 240V power.  It seems that most 5
> > hp vfds do not allow single phase input.  I found this:
> > http://www.gohz.com/5hp-vfd Does anyone have experience with GOHZ or
> > other affordable 5 hp drives that will run on single phase?
> >
> > John Figie
> > --
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>
>
>

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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

The Precision Electric guys are really good.   I've been in their motor 
rewind shop.    I was involved in a re-control job on a paper web line 
and they rewound some failing DC motors over Christmas.. they did a 
really great job.
They also have a large repair area where they repair drives, servo, VFD, 
etc.    They knows drives to the component level which is rather rare 
these days.

Nothing they do is hobby related.   Its all industrial/heavy industrial.

Regarding the $132 price... I agree.   Just too cheap.  I would avoid.

Les mentioned Yaskawa drives for a reasonable price.    They have a very 
good reputation and are not normally low priced drives.


Dave

On 1/2/2018 10:37 AM, John Figie wrote:

Dave,

Yes I want a 5hp vfd with single phase input and that is why i am
interested in the gohz GK3000-2S0037 @ $294.  On amazon there are some even
cheaper @$132 but there is no on line manual and i don't think a 5 hp
single phase input drive can be made that cheap.

I read the article you referenced https://www.precisi
on-elec.com/derate-three-phase-vfd-for-single-phase-power/ but I don't
agree with it because he is simply scaling the input current by the 3 phase
to single phase conversion constant of square root of 3 or 1.73.  This
holds true for the input current but not the internal DC bus capacitor RMS
ripple current which causes capacitor heating.

On the other hand there is a huge difference between occasional hobby use
and industrial use so maybe I shouldn't be so finicky.

John Figie

On Jan 2, 2018 8:03 AM, "Dave Cole"  wrote:


Except that he needs a 5 hp single phase inverter.   Those are a little
harder to find and  a lot more expensive... near $1000 for this AC Tech
Drive.

https://www.wolfautomation.com/products/ac-drives/ac-drive-
5hp-208-240vac-1-3-phase-input

Phase converters do have some phase current balance issues but for low
tech - I just want to run the machine - they are hard to beat unless you
are running the machine a lot or at a constant full load.   I have a rotary
phase converter built with a 10hp motor 15+ years ago and it will power a
10 hp Quincy two stage air compressor at slightly reduced pressure.   I
probably put about $250 into that phase converter 15 years ago.   Good
motor run caps are the key.   Those can be bought off Ebay and Surplus
Center, etc.

There is a small down the road that manufactures steel stakes for the Army
Corp of engineers and landscape contractors in large quantities and he has
an assortment of small punch presses and the entire shop runs off single
phase power with a phase converter. So it can be done.   Sometimes low tech
is enough and if you don't need variable speed it can work well.

Dave

On 1/1/2018 7:58 PM, Gregg Eshelman via Emc-users wrote:


Or just get a proper single phase to three phase VFD and do the job
right. For under $200 you can get a 230V 1PH in drive that'll run up to a
3HP 3PH
https://www.wolfautomation.com/products/ac-drives

  On Monday, January 1, 2018, 10:49:12 AM MST, John Figie <
zephyr9...@gmail.com> wrote:
 All,

Thanks for your replies.

My real question was to see if anyone had used GOHZ or some other cheap
drive.  I currently run all my machines from a home made rotary phase
converter.  It works pretty well but does not produce the best 3 phase.
Yes I know you can use capacitors to adjust the outputs which I have.  The
rotary converter has been running in my shop for about 15 years. I have a
hydraulic automatic surface grinder that does n't like being run from the
phase converter.  The pump motor overheats when run from my rotary
converter, I think maybe this is because the motor runs near full load.

I know I can use a larger drive and derate it to use on single phase
power,
but that seems like a much more expensive option.
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Re: [Emc-users] 240V single phase input vfd

[John Figie]

That would be a poor design if no braking resistor causes it to blow up.
Once the bus gets pushed up to its max limit it should let the motor coast
to a stop.

John Figie

On Jan 2, 2018 9:58 AM, "Eric Keller"  wrote:

> On Tue, Jan 2, 2018 at 10:46 AM, Les Newell 
> wrote:
>
> >
> >  I would avoid the Huanyang drives as they have a reputation for blowing
> > up.
> >
> > Les
> >
> >
> >
> My thought is they probably blow up because they have no braking circuitry
> installed, even internal to the drive. Unless it gets added. The gohz seems
> to be the same hardware/firmware just from a short scan of the manual.
> Wonder if it has a braking circuit.
> 
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Re: [Emc-users] 240V single phase input vfd

[Eric Keller]

On Tue, Jan 2, 2018 at 10:46 AM, Les Newell 
wrote:

>
>  I would avoid the Huanyang drives as they have a reputation for blowing
> up.
>
> Les
>
>
>
My thought is they probably blow up because they have no braking circuitry
installed, even internal to the drive. Unless it gets added. The gohz seems
to be the same hardware/firmware just from a short scan of the manual.
Wonder if it has a braking circuit.
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Re: [Emc-users] 240V single phase input vfd

[Les Newell]

I've run 3 phase inverters on single phase several times with no real 
problems. For example my lathe has a 7.5kw motor with a 7.5kw inverter 
and it works fine on single phase. I guess it helps that I am using a 
240->415 auto transformer which probably has a significantly higher 
impedance than a direct mains connection.


Les



I read the article you referenced https://www.precisi
on-elec.com/derate-three-phase-vfd-for-single-phase-power/ but I don't
agree with it because he is simply scaling the input current by the 3 phase
to single phase conversion constant of square root of 3 or 1.73.  This
holds true for the input current but not the internal DC bus capacitor RMS
ripple current which causes capacitor heating.

On the other hand there is a huge difference between occasional hobby use
and industrial use so maybe I shouldn't be so finicky.



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Re: [Emc-users] 240V single phase input vfd

[Andy Pugh]

> On 2 Jan 2018, at 15:26, Eric Keller  wrote:
> 
> The Huan Yang line of VFDs sold on ebay feature a 4kw version that will run
> off of single phase.  The only problem with them is lack of braking on some
> models.  The Mach crew have figured out the modbus connections. About $200.

The LinuxCNC crew have figured out the serial connection too (it isn’t exactly 
Modbus) and there is a driver. 

I am using that combo to run my lathe. 



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Re: [Emc-users] 240V single phase input vfd

[Les Newell]

In the UK, inverterdrive.com have really reasonable prices. Probably not 
too useful for you but this link shows all of their 240V single phase 
drives 
. 
You could see if other companies local to you stock any of those drives. 
Their Yaskawa V1000 drive is only a bit more than the gohz equivalent. I 
don't know easily available Yaskawa drives are in the US. Yaskawa are a 
well known and reliable brand.


 I would avoid the Huanyang drives as they have a reputation for 
blowing up.


Les



On 01/01/2018 00:45, John Figie wrote:

I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
only have single phase 240V power.  It seems that most 5 hp vfds do not
allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
Does anyone have experience with GOHZ or other affordable 5 hp drives that
will run on single phase?

John Figie
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Re: [Emc-users] 240V single phase input vfd

[John Figie]

Dave,

Yes I want a 5hp vfd with single phase input and that is why i am
interested in the gohz GK3000-2S0037 @ $294.  On amazon there are some even
cheaper @$132 but there is no on line manual and i don't think a 5 hp
single phase input drive can be made that cheap.

I read the article you referenced https://www.precisi
on-elec.com/derate-three-phase-vfd-for-single-phase-power/ but I don't
agree with it because he is simply scaling the input current by the 3 phase
to single phase conversion constant of square root of 3 or 1.73.  This
holds true for the input current but not the internal DC bus capacitor RMS
ripple current which causes capacitor heating.

On the other hand there is a huge difference between occasional hobby use
and industrial use so maybe I shouldn't be so finicky.

John Figie

On Jan 2, 2018 8:03 AM, "Dave Cole"  wrote:

> Except that he needs a 5 hp single phase inverter.   Those are a little
> harder to find and  a lot more expensive... near $1000 for this AC Tech
> Drive.
>
> https://www.wolfautomation.com/products/ac-drives/ac-drive-
> 5hp-208-240vac-1-3-phase-input
>
> Phase converters do have some phase current balance issues but for low
> tech - I just want to run the machine - they are hard to beat unless you
> are running the machine a lot or at a constant full load.   I have a rotary
> phase converter built with a 10hp motor 15+ years ago and it will power a
> 10 hp Quincy two stage air compressor at slightly reduced pressure.   I
> probably put about $250 into that phase converter 15 years ago.   Good
> motor run caps are the key.   Those can be bought off Ebay and Surplus
> Center, etc.
>
> There is a small down the road that manufactures steel stakes for the Army
> Corp of engineers and landscape contractors in large quantities and he has
> an assortment of small punch presses and the entire shop runs off single
> phase power with a phase converter. So it can be done.   Sometimes low tech
> is enough and if you don't need variable speed it can work well.
>
> Dave
>
> On 1/1/2018 7:58 PM, Gregg Eshelman via Emc-users wrote:
>
>> Or just get a proper single phase to three phase VFD and do the job
>> right. For under $200 you can get a 230V 1PH in drive that'll run up to a
>> 3HP 3PH
>> https://www.wolfautomation.com/products/ac-drives
>>
>>  On Monday, January 1, 2018, 10:49:12 AM MST, John Figie <
>> zephyr9...@gmail.com> wrote:
>> All,
>>
>> Thanks for your replies.
>>
>> My real question was to see if anyone had used GOHZ or some other cheap
>> drive.  I currently run all my machines from a home made rotary phase
>> converter.  It works pretty well but does not produce the best 3 phase.
>> Yes I know you can use capacitors to adjust the outputs which I have.  The
>> rotary converter has been running in my shop for about 15 years. I have a
>> hydraulic automatic surface grinder that does n't like being run from the
>> phase converter.  The pump motor overheats when run from my rotary
>> converter, I think maybe this is because the motor runs near full load.
>>
>> I know I can use a larger drive and derate it to use on single phase
>> power,
>> but that seems like a much more expensive option.
>>---
>> ---
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>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] 240V single phase input vfd

[Eric Keller]

On Tue, Jan 2, 2018 at 9:04 AM, Dave Cole  wrote:

> Except that he needs a 5 hp single phase inverter.   Those are a little
> harder to find and  a lot more expensive... near $1000 for this AC Tech
> Drive.


The Huan Yang line of VFDs sold on ebay feature a 4kw version that will run
off of single phase.  The only problem with them is lack of braking on some
models.  The Mach crew have figured out the modbus connections. About $200.
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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

Except that he needs a 5 hp single phase inverter.   Those are a little 
harder to find and  a lot more expensive... near $1000 for this AC Tech 
Drive.


https://www.wolfautomation.com/products/ac-drives/ac-drive-5hp-208-240vac-1-3-phase-input

Phase converters do have some phase current balance issues but for low 
tech - I just want to run the machine - they are hard to beat unless you 
are running the machine a lot or at a constant full load.   I have a 
rotary phase converter built with a 10hp motor 15+ years ago and it will 
power a 10 hp Quincy two stage air compressor at slightly reduced 
pressure.   I probably put about $250 into that phase converter 15 years 
ago.   Good motor run caps are the key.   Those can be bought off Ebay 
and Surplus Center, etc.


There is a small down the road that manufactures steel stakes for the 
Army Corp of engineers and landscape contractors in large quantities and 
he has an assortment of small punch presses and the entire shop runs off 
single phase power with a phase converter. So it can be done.   
Sometimes low tech is enough and if you don't need variable speed it can 
work well.


Dave

On 1/1/2018 7:58 PM, Gregg Eshelman via Emc-users wrote:

Or just get a proper single phase to three phase VFD and do the job right. For 
under $200 you can get a 230V 1PH in drive that'll run up to a 3HP 3PH
https://www.wolfautomation.com/products/ac-drives

 On Monday, January 1, 2018, 10:49:12 AM MST, John Figie 
 wrote:
  
  All,


Thanks for your replies.

My real question was to see if anyone had used GOHZ or some other cheap
drive.  I currently run all my machines from a home made rotary phase
converter.  It works pretty well but does not produce the best 3 phase.
Yes I know you can use capacitors to adjust the outputs which I have.  The
rotary converter has been running in my shop for about 15 years. I have a
hydraulic automatic surface grinder that does n't like being run from the
phase converter.  The pump motor overheats when run from my rotary
converter, I think maybe this is because the motor runs near full load.

I know I can use a larger drive and derate it to use on single phase power,
but that seems like a much more expensive option.
   
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Re: [Emc-users] 240V single phase input vfd

[John Dammeyer]

Thanks.
 
Have to investigate those G codes in more depth.

John


> -Original Message-
> From: Gene Heskett [mailto:ghesk...@shentel.net]
> Sent: January-01-18 6:19 PM
> To: emc-users@lists.sourceforge.net
> Subject: Re: [Emc-users] 240V single phase input vfd
> 
> On Monday 01 January 2018 18:59:08 John Dammeyer wrote:
> 
> > Most of those VFDs appear to be open loop.
> >
> > What's normally done with LinuxCNC for closed loop spindle control?
> > Say you want to do the equivalent of internal threading on a lathe.
> > Is a run-out area required or can LinuxCNC control the spindle speed
> > in sync with the Z axis so either a tap or cutter follows the threads?
> >
> > Is an AC Servo (with encoder) even required on a CNC system or just
> > open loop variable speed control?
> >
> > Thanks
> > John
> >
> All thats needed is a reliable way to track the spindle as it turns.
> 
> From that and the 1/tpi or tpmm of the tap, the rest of the required
> motion to carry the tap into the hole in synch with the taps own
> threads, and a reversable spindle to back the tap out of the hole,
> totally in synch with the taps own threads.  This is G33.1 at work.
> 
> Switching from a tap to a single tooth, usually triangular cutter, (using
> G76) will drive the cutter at the desired number of threads per unit of
> travel again to cut the thread, retracting the cutter over a programable
> distance at the end of the thread, or drive the tool into the thread at
> the beginning of the cut or both. Here the spindle synch is disconnected
> at the end of the cut, the tool is taken back to a point about 1 turn
> away from the start of the thread, and synchronized motion is
> re-established at the next index pulse from the encoder on the spindle.
> Here also, the tool is driven at 29.5 to 30 degrees as its driven into
> thread so that the cutting action is only on the leading edge of the
> tool, much cleaner cut.
> 
> G76 has the concept of a drive line, which can be adjusted for increased
> clearance during the tools retrace move, this and the length of the
> extraction move can be exploited to make tapered threads with very low
> taper angles. That in turn can make an extremely high pressure
> compression joint for attaching a extended drive shaft to the end of a
> ball screw.
> >
> Both of those 2 gcodes need carefull study. They can be very powerfull
> when used correctly.
> >
> >
> >
> >
> >
> > --
> > Check out the vibrant tech community on one of the world's
> > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> > ___
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> > https://lists.sourceforge.net/lists/listinfo/emc-users
> 
> 
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page <http://geneslinuxbox.net:6309/gene>
> 
>

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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Monday 01 January 2018 18:59:08 John Dammeyer wrote:

> Most of those VFDs appear to be open loop.
>
> What's normally done with LinuxCNC for closed loop spindle control?  
> Say you want to do the equivalent of internal threading on a lathe. 
> Is a run-out area required or can LinuxCNC control the spindle speed
> in sync with the Z axis so either a tap or cutter follows the threads?
>
> Is an AC Servo (with encoder) even required on a CNC system or just
> open loop variable speed control?
>
> Thanks
> John
>
All thats needed is a reliable way to track the spindle as it turns.

>From that and the 1/tpi or tpmm of the tap, the rest of the required 
motion to carry the tap into the hole in synch with the taps own 
threads, and a reversable spindle to back the tap out of the hole, 
totally in synch with the taps own threads.  This is G33.1 at work.

Switching from a tap to a single tooth, usually triangular cutter, (using 
G76) will drive the cutter at the desired number of threads per unit of 
travel again to cut the thread, retracting the cutter over a programable 
distance at the end of the thread, or drive the tool into the thread at 
the beginning of the cut or both. Here the spindle synch is disconnected 
at the end of the cut, the tool is taken back to a point about 1 turn 
away from the start of the thread, and synchronized motion is 
re-established at the next index pulse from the encoder on the spindle. 
Here also, the tool is driven at 29.5 to 30 degrees as its driven into 
thread so that the cutting action is only on the leading edge of the 
tool, much cleaner cut.

G76 has the concept of a drive line, which can be adjusted for increased 
clearance during the tools retrace move, this and the length of the 
extraction move can be exploited to make tapered threads with very low 
taper angles. That in turn can make an extremely high pressure 
compression joint for attaching a extended drive shaft to the end of a 
ball screw.
>
Both of those 2 gcodes need carefull study. They can be very powerfull 
when used correctly.
>
>
>
>
>
> --
> Check out the vibrant tech community on one of the world's
> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
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> https://lists.sourceforge.net/lists/listinfo/emc-users


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] 240V single phase input vfd

[John Dammeyer]

Super.
Thanks
John

> -Original Message-
> From: John Figie [mailto:zephyr9...@gmail.com]
> Sent: January-01-18 4:25 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] 240V single phase input vfd
> 
> John,
> 
> To be clear you need either closed loop servos or steppers on all of the
> motion axis for CNC control.  The spindle however can be open loop just as
> Jon said.  A spindle encoder essentially allows all other motion to be
> electronically geared to the spindle motion. You can run linuxCNC without
a
> spindle encoder but then you cannot do ridged tapping or threading.
> 
> 
> 
> John Figie
> 
> On Mon, Jan 1, 2018 at 6:06 PM, Jon Elson  wrote:
> 
> > On 01/01/2018 05:59 PM, John Dammeyer wrote:
> >
> >> Most of those VFDs appear to be open loop.
> >>
> >> What's normally done with LinuxCNC for closed loop spindle control?
Say
> >> you want to do the equivalent of internal threading on a lathe.  Is a
> >> run-out area required or can LinuxCNC control the spindle speed in sync
> >> with the Z axis so either a tap or cutter follows the threads?
> >>
> >> Is an AC Servo (with encoder) even required on a CNC system or just
open
> >> loop variable speed control?
> >>
> >>
> >> I run entirely open-loop, and it works fine.  You do need a spindle
> > encoder for any threading operation.
> > On my minimill, the spindle slows noticeably when threading, but the Z
> > axis stays in synch with the spindle,
> > and it works fine.  You need both a "run-in" and "run-out" distance, as
> > the Z axis cannot start and stop
> > instantly.
> >
> > Jon
> >
> >
> > 
> > --
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> > engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
>

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Re: [Emc-users] 240V single phase input vfd

[Gregg Eshelman via Emc-users]

Or just get a proper single phase to three phase VFD and do the job right. For 
under $200 you can get a 230V 1PH in drive that'll run up to a 3HP 3PH
https://www.wolfautomation.com/products/ac-drives 

On Monday, January 1, 2018, 10:49:12 AM MST, John Figie 
 wrote:  
 
 All,

Thanks for your replies.

My real question was to see if anyone had used GOHZ or some other cheap
drive.  I currently run all my machines from a home made rotary phase
converter.  It works pretty well but does not produce the best 3 phase.
Yes I know you can use capacitors to adjust the outputs which I have.  The
rotary converter has been running in my shop for about 15 years. I have a
hydraulic automatic surface grinder that does n't like being run from the
phase converter.  The pump motor overheats when run from my rotary
converter, I think maybe this is because the motor runs near full load.

I know I can use a larger drive and derate it to use on single phase power,
but that seems like a much more expensive option.
  
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Re: [Emc-users] 240V single phase input vfd

[John Figie]

John,

To be clear you need either closed loop servos or steppers on all of the
motion axis for CNC control.  The spindle however can be open loop just as
Jon said.  A spindle encoder essentially allows all other motion to be
electronically geared to the spindle motion. You can run linuxCNC without a
spindle encoder but then you cannot do ridged tapping or threading.



John Figie

On Mon, Jan 1, 2018 at 6:06 PM, Jon Elson  wrote:

> On 01/01/2018 05:59 PM, John Dammeyer wrote:
>
>> Most of those VFDs appear to be open loop.
>>
>> What's normally done with LinuxCNC for closed loop spindle control?   Say
>> you want to do the equivalent of internal threading on a lathe.  Is a
>> run-out area required or can LinuxCNC control the spindle speed in sync
>> with the Z axis so either a tap or cutter follows the threads?
>>
>> Is an AC Servo (with encoder) even required on a CNC system or just open
>> loop variable speed control?
>>
>>
>> I run entirely open-loop, and it works fine.  You do need a spindle
> encoder for any threading operation.
> On my minimill, the spindle slows noticeably when threading, but the Z
> axis stays in synch with the spindle,
> and it works fine.  You need both a "run-in" and "run-out" distance, as
> the Z axis cannot start and stop
> instantly.
>
> Jon
>
>
> 
> --
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Re: [Emc-users] 240V single phase input vfd

[Jon Elson]

On 01/01/2018 05:59 PM, John Dammeyer wrote:

Most of those VFDs appear to be open loop.

What's normally done with LinuxCNC for closed loop spindle control?   Say you 
want to do the equivalent of internal threading on a lathe.  Is a run-out area 
required or can LinuxCNC control the spindle speed in sync with the Z axis so 
either a tap or cutter follows the threads?

Is an AC Servo (with encoder) even required on a CNC system or just open loop 
variable speed control?


I run entirely open-loop, and it works fine.  You do need a 
spindle encoder for any threading operation.
On my minimill, the spindle slows noticeably when threading, 
but the Z axis stays in synch with the spindle,
and it works fine.  You need both a "run-in" and "run-out" 
distance, as the Z axis cannot start and stop

instantly.

Jon

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Re: [Emc-users] 240V single phase input vfd

[John Dammeyer]

Most of those VFDs appear to be open loop.  

What's normally done with LinuxCNC for closed loop spindle control?   Say you 
want to do the equivalent of internal threading on a lathe.  Is a run-out area 
required or can LinuxCNC control the spindle speed in sync with the Z axis so 
either a tap or cutter follows the threads?

Is an AC Servo (with encoder) even required on a CNC system or just open loop 
variable speed control?

Thanks
John








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Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

Might want to read this.   I know the owner of this company.  He's a 
good guy.

https://www.precision-elec.com/derate-three-phase-vfd-for-single-phase-power/

There are other cheap 5hp drives on Ebay..  but this would probably need 
to be derated for single phase..  or not??

https://www.ebay.com/itm/UPDATED-220V-4KW-5HP-VARIABLE-FREQUENCY-DRIVE-INVERTER-VFD-NEW-/272864297426?_trksid=p2349526.m4383.l4275.c10

Really cheap!

Dave

On 1/1/2018 3:53 PM, Greg Bernard wrote:

Yes I did! Sorry.
https://www.driveswarehouse.com/?gclid=Cj0KCQiAsqLSBRCmARIsAL4Pa9T6TYOzrv9mH_DO_eki29PtK-inTHt_0W3FwgAUKC-Z19-jeWD0krAaAjZxEALw_wcB#&&fb=iv

On Mon, Jan 1, 2018 at 2:48 PM, John Figie  wrote:


Greg,

I don't see a link.  Did you forget to add it?

John Figie

On Jan 1, 2018 1:32 PM, "Greg Bernard"  wrote:


Check out this place. Good prices on drives and motors.

On Mon, Jan 1, 2018 at 11:46 AM, John Figie 

wrote:

All,

Thanks for your replies.

My real question was to see if anyone had used GOHZ or some other cheap
drive.  I currently run all my machines from a home made rotary phase
converter.  It works pretty well but does not produce the best 3 phase.
Yes I know you can use capacitors to adjust the outputs which I have.

The

rotary converter has been running in my shop for about 15 years. I

have a

hydraulic automatic surface grinder that does n't like being run from

the

phase converter.  The pump motor overheats when run from my rotary
converter, I think maybe this is because the motor runs near full load.

I know I can use a larger drive and derate it to use on single phase

power,

but that seems like a much more expensive option. Some drives have

missing

phase detection that I could probably trick with some kind of AC

input. I

think the concerns for me are that the input diode bridge will see the
input current distributed among 4 diodes but instead of 6.  Also the
conduction angle of the diodes will be longer since all of the input
current must be supplied from the single phase rather than overlapping
phases. Finally the stress on the DC bus capacitors will be much higher

due

to the higher DC bus ripple. This bus capacitor RMS ripple current

degrades

the capacitors due to internal heating.

Now since this is a lathe spindle and I am a hobbyist how often will I
really need to load the machine to 5hp? Probably not very often. Also I

can

set the acceleration/deceleration to a conservative value to reduce the
peak currents.  Additionally I think I could replace my rotary phase
converter (which is kind of noisy) with the VFD which will produce a
different kind of noise (electrical) but It will be quiet.

My motivation for asking about GOHZ is that I just discovered them and

they

have a $294 drive rated for single phase input so I would presume that

the

additional stress was considered in the design.

Automation direct does not list any VFDs of 5hp or higher rated for
operation from a single phase.

Here is what I have found so far listed on a spreadsheet.
https://docs.google.com/spreadsheets/d/1YS-

QKbJIlBYDSPdWAelA6ZF0zbS30HrHn

qE02-opSRI/edit?usp=sharing

If anyone knows of other options please let me know.

John Figie

On Mon, Jan 1, 2018 at 11:09 AM, Dave Cole 
wrote:


I have heard that sometimes you can get around that by putting  a

motor

run capacitor between one of the live phases and the unconnected

input

power terminal.
That can sometimes trick the drive into thinking that it has power at

all

of the terminals.

Back when VFDs were very expensive the way to do this was with a

static

or

rotary phase converter.
I have a 5 hp 3 phase motor on an old turret lathe spindle that I run

off

a rotary phase converter that I put together a long time ago.It
works.   You can find how to instructions on how to build one on the
net.You will need a 3 to 10 hp 3 phase motor as a base device for

the

converter.

You can also make a static 3 phase adapter for your existing motor

simply

by adding some capacitors to "power" the third phase.  Info for that

is

also on the net.

Dave


On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:


Usually there is a diode rectifier at the input but I guess they

also

measure voltage and refuse to run then to low so experience is

important.

On Sun, 31 Dec 2017 18:45:44 -0600
John Figie  wrote:

I have a 5 hp 240V 3 phase induction motor that is for a lathe

spindle.  I

only have single phase 240V power.  It seems that most 5 hp vfds do

not

allow single phase input.  I found this:

http://www.gohz.com/5hp-vfd

Does anyone have experience with GOHZ or other affordable 5 hp

drives

that
will run on single phase?

John Figie

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Re: [Emc-users] 240V single phase input vfd

[Greg Bernard]

Yes I did! Sorry.
https://www.driveswarehouse.com/?gclid=Cj0KCQiAsqLSBRCmARIsAL4Pa9T6TYOzrv9mH_DO_eki29PtK-inTHt_0W3FwgAUKC-Z19-jeWD0krAaAjZxEALw_wcB#&&fb=iv

On Mon, Jan 1, 2018 at 2:48 PM, John Figie  wrote:

> Greg,
>
> I don't see a link.  Did you forget to add it?
>
> John Figie
>
> On Jan 1, 2018 1:32 PM, "Greg Bernard"  wrote:
>
> > Check out this place. Good prices on drives and motors.
> >
> > On Mon, Jan 1, 2018 at 11:46 AM, John Figie 
> wrote:
> >
> > > All,
> > >
> > > Thanks for your replies.
> > >
> > > My real question was to see if anyone had used GOHZ or some other cheap
> > > drive.  I currently run all my machines from a home made rotary phase
> > > converter.  It works pretty well but does not produce the best 3 phase.
> > > Yes I know you can use capacitors to adjust the outputs which I have.
> > The
> > > rotary converter has been running in my shop for about 15 years. I
> have a
> > > hydraulic automatic surface grinder that does n't like being run from
> the
> > > phase converter.  The pump motor overheats when run from my rotary
> > > converter, I think maybe this is because the motor runs near full load.
> > >
> > > I know I can use a larger drive and derate it to use on single phase
> > power,
> > > but that seems like a much more expensive option. Some drives have
> > missing
> > > phase detection that I could probably trick with some kind of AC
> input. I
> > > think the concerns for me are that the input diode bridge will see the
> > > input current distributed among 4 diodes but instead of 6.  Also the
> > > conduction angle of the diodes will be longer since all of the input
> > > current must be supplied from the single phase rather than overlapping
> > > phases. Finally the stress on the DC bus capacitors will be much higher
> > due
> > > to the higher DC bus ripple. This bus capacitor RMS ripple current
> > degrades
> > > the capacitors due to internal heating.
> > >
> > > Now since this is a lathe spindle and I am a hobbyist how often will I
> > > really need to load the machine to 5hp? Probably not very often. Also I
> > can
> > > set the acceleration/deceleration to a conservative value to reduce the
> > > peak currents.  Additionally I think I could replace my rotary phase
> > > converter (which is kind of noisy) with the VFD which will produce a
> > > different kind of noise (electrical) but It will be quiet.
> > >
> > > My motivation for asking about GOHZ is that I just discovered them and
> > they
> > > have a $294 drive rated for single phase input so I would presume that
> > the
> > > additional stress was considered in the design.
> > >
> > > Automation direct does not list any VFDs of 5hp or higher rated for
> > > operation from a single phase.
> > >
> > > Here is what I have found so far listed on a spreadsheet.
> > > https://docs.google.com/spreadsheets/d/1YS-
> > QKbJIlBYDSPdWAelA6ZF0zbS30HrHn
> > > qE02-opSRI/edit?usp=sharing
> > >
> > > If anyone knows of other options please let me know.
> > >
> > > John Figie
> > >
> > > On Mon, Jan 1, 2018 at 11:09 AM, Dave Cole 
> > > wrote:
> > >
> > > > I have heard that sometimes you can get around that by putting  a
> motor
> > > > run capacitor between one of the live phases and the unconnected
> input
> > > > power terminal.
> > > > That can sometimes trick the drive into thinking that it has power at
> > all
> > > > of the terminals.
> > > >
> > > > Back when VFDs were very expensive the way to do this was with a
> static
> > > or
> > > > rotary phase converter.
> > > > I have a 5 hp 3 phase motor on an old turret lathe spindle that I run
> > off
> > > > a rotary phase converter that I put together a long time ago.It
> > > > works.   You can find how to instructions on how to build one on the
> > > > net.You will need a 3 to 10 hp 3 phase motor as a base device for
> > the
> > > > converter.
> > > >
> > > > You can also make a static 3 phase adapter for your existing motor
> > simply
> > > > by adding some capacitors to "power" the third phase.  Info for that
> is
> > > > also on the net.
> > > >
> > > > Dave
> > > >
> > > >
> > > > On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:
> > > >
> > > >> Usually there is a diode rectifier at the input but I guess they
> also
> > > >> measure voltage and refuse to run then to low so experience is
> > > important.
> > > >>
> > > >> On Sun, 31 Dec 2017 18:45:44 -0600
> > > >> John Figie  wrote:
> > > >>
> > > >> I have a 5 hp 240V 3 phase induction motor that is for a lathe
> > > spindle.  I
> > > >>> only have single phase 240V power.  It seems that most 5 hp vfds do
> > not
> > > >>> allow single phase input.  I found this:
> > http://www.gohz.com/5hp-vfd
> > > >>> Does anyone have experience with GOHZ or other affordable 5 hp
> drives
> > > >>> that
> > > >>> will run on single phase?
> > > >>>
> > > >>> John Figie
> > > >>> 
> > > >>> --
> > > >>> Check out the vibrant tech community on o

Re: [Emc-users] 240V single phase input vfd

[John Figie]

Greg,

I don't see a link.  Did you forget to add it?

John Figie

On Jan 1, 2018 1:32 PM, "Greg Bernard"  wrote:

> Check out this place. Good prices on drives and motors.
>
> On Mon, Jan 1, 2018 at 11:46 AM, John Figie  wrote:
>
> > All,
> >
> > Thanks for your replies.
> >
> > My real question was to see if anyone had used GOHZ or some other cheap
> > drive.  I currently run all my machines from a home made rotary phase
> > converter.  It works pretty well but does not produce the best 3 phase.
> > Yes I know you can use capacitors to adjust the outputs which I have.
> The
> > rotary converter has been running in my shop for about 15 years. I have a
> > hydraulic automatic surface grinder that does n't like being run from the
> > phase converter.  The pump motor overheats when run from my rotary
> > converter, I think maybe this is because the motor runs near full load.
> >
> > I know I can use a larger drive and derate it to use on single phase
> power,
> > but that seems like a much more expensive option. Some drives have
> missing
> > phase detection that I could probably trick with some kind of AC input. I
> > think the concerns for me are that the input diode bridge will see the
> > input current distributed among 4 diodes but instead of 6.  Also the
> > conduction angle of the diodes will be longer since all of the input
> > current must be supplied from the single phase rather than overlapping
> > phases. Finally the stress on the DC bus capacitors will be much higher
> due
> > to the higher DC bus ripple. This bus capacitor RMS ripple current
> degrades
> > the capacitors due to internal heating.
> >
> > Now since this is a lathe spindle and I am a hobbyist how often will I
> > really need to load the machine to 5hp? Probably not very often. Also I
> can
> > set the acceleration/deceleration to a conservative value to reduce the
> > peak currents.  Additionally I think I could replace my rotary phase
> > converter (which is kind of noisy) with the VFD which will produce a
> > different kind of noise (electrical) but It will be quiet.
> >
> > My motivation for asking about GOHZ is that I just discovered them and
> they
> > have a $294 drive rated for single phase input so I would presume that
> the
> > additional stress was considered in the design.
> >
> > Automation direct does not list any VFDs of 5hp or higher rated for
> > operation from a single phase.
> >
> > Here is what I have found so far listed on a spreadsheet.
> > https://docs.google.com/spreadsheets/d/1YS-
> QKbJIlBYDSPdWAelA6ZF0zbS30HrHn
> > qE02-opSRI/edit?usp=sharing
> >
> > If anyone knows of other options please let me know.
> >
> > John Figie
> >
> > On Mon, Jan 1, 2018 at 11:09 AM, Dave Cole 
> > wrote:
> >
> > > I have heard that sometimes you can get around that by putting  a motor
> > > run capacitor between one of the live phases and the unconnected input
> > > power terminal.
> > > That can sometimes trick the drive into thinking that it has power at
> all
> > > of the terminals.
> > >
> > > Back when VFDs were very expensive the way to do this was with a static
> > or
> > > rotary phase converter.
> > > I have a 5 hp 3 phase motor on an old turret lathe spindle that I run
> off
> > > a rotary phase converter that I put together a long time ago.It
> > > works.   You can find how to instructions on how to build one on the
> > > net.You will need a 3 to 10 hp 3 phase motor as a base device for
> the
> > > converter.
> > >
> > > You can also make a static 3 phase adapter for your existing motor
> simply
> > > by adding some capacitors to "power" the third phase.  Info for that is
> > > also on the net.
> > >
> > > Dave
> > >
> > >
> > > On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:
> > >
> > >> Usually there is a diode rectifier at the input but I guess they also
> > >> measure voltage and refuse to run then to low so experience is
> > important.
> > >>
> > >> On Sun, 31 Dec 2017 18:45:44 -0600
> > >> John Figie  wrote:
> > >>
> > >> I have a 5 hp 240V 3 phase induction motor that is for a lathe
> > spindle.  I
> > >>> only have single phase 240V power.  It seems that most 5 hp vfds do
> not
> > >>> allow single phase input.  I found this:
> http://www.gohz.com/5hp-vfd
> > >>> Does anyone have experience with GOHZ or other affordable 5 hp drives
> > >>> that
> > >>> will run on single phase?
> > >>>
> > >>> John Figie
> > >>> 
> > >>> --
> > >>> Check out the vibrant tech community on one of the world's most
> > >>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> > >>> ___
> > >>> Emc-users mailing list
> > >>> Emc-users@lists.sourceforge.net
> > >>> https://lists.sourceforge.net/lists/listinfo/emc-users
> > >>>
> > >> 
> > >> --
> > >> Check out the vibrant tech community on one of the world's most
> > >> enga

Re: [Emc-users] 240V single phase input vfd

[Greg Bernard]

Check out this place. Good prices on drives and motors.

On Mon, Jan 1, 2018 at 11:46 AM, John Figie  wrote:

> All,
>
> Thanks for your replies.
>
> My real question was to see if anyone had used GOHZ or some other cheap
> drive.  I currently run all my machines from a home made rotary phase
> converter.  It works pretty well but does not produce the best 3 phase.
> Yes I know you can use capacitors to adjust the outputs which I have.  The
> rotary converter has been running in my shop for about 15 years. I have a
> hydraulic automatic surface grinder that does n't like being run from the
> phase converter.  The pump motor overheats when run from my rotary
> converter, I think maybe this is because the motor runs near full load.
>
> I know I can use a larger drive and derate it to use on single phase power,
> but that seems like a much more expensive option. Some drives have missing
> phase detection that I could probably trick with some kind of AC input. I
> think the concerns for me are that the input diode bridge will see the
> input current distributed among 4 diodes but instead of 6.  Also the
> conduction angle of the diodes will be longer since all of the input
> current must be supplied from the single phase rather than overlapping
> phases. Finally the stress on the DC bus capacitors will be much higher due
> to the higher DC bus ripple. This bus capacitor RMS ripple current degrades
> the capacitors due to internal heating.
>
> Now since this is a lathe spindle and I am a hobbyist how often will I
> really need to load the machine to 5hp? Probably not very often. Also I can
> set the acceleration/deceleration to a conservative value to reduce the
> peak currents.  Additionally I think I could replace my rotary phase
> converter (which is kind of noisy) with the VFD which will produce a
> different kind of noise (electrical) but It will be quiet.
>
> My motivation for asking about GOHZ is that I just discovered them and they
> have a $294 drive rated for single phase input so I would presume that the
> additional stress was considered in the design.
>
> Automation direct does not list any VFDs of 5hp or higher rated for
> operation from a single phase.
>
> Here is what I have found so far listed on a spreadsheet.
> https://docs.google.com/spreadsheets/d/1YS-QKbJIlBYDSPdWAelA6ZF0zbS30HrHn
> qE02-opSRI/edit?usp=sharing
>
> If anyone knows of other options please let me know.
>
> John Figie
>
> On Mon, Jan 1, 2018 at 11:09 AM, Dave Cole 
> wrote:
>
> > I have heard that sometimes you can get around that by putting  a motor
> > run capacitor between one of the live phases and the unconnected input
> > power terminal.
> > That can sometimes trick the drive into thinking that it has power at all
> > of the terminals.
> >
> > Back when VFDs were very expensive the way to do this was with a static
> or
> > rotary phase converter.
> > I have a 5 hp 3 phase motor on an old turret lathe spindle that I run off
> > a rotary phase converter that I put together a long time ago.It
> > works.   You can find how to instructions on how to build one on the
> > net.You will need a 3 to 10 hp 3 phase motor as a base device for the
> > converter.
> >
> > You can also make a static 3 phase adapter for your existing motor simply
> > by adding some capacitors to "power" the third phase.  Info for that is
> > also on the net.
> >
> > Dave
> >
> >
> > On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:
> >
> >> Usually there is a diode rectifier at the input but I guess they also
> >> measure voltage and refuse to run then to low so experience is
> important.
> >>
> >> On Sun, 31 Dec 2017 18:45:44 -0600
> >> John Figie  wrote:
> >>
> >> I have a 5 hp 240V 3 phase induction motor that is for a lathe
> spindle.  I
> >>> only have single phase 240V power.  It seems that most 5 hp vfds do not
> >>> allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
> >>> Does anyone have experience with GOHZ or other affordable 5 hp drives
> >>> that
> >>> will run on single phase?
> >>>
> >>> John Figie
> >>> 
> >>> --
> >>> Check out the vibrant tech community on one of the world's most
> >>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >>> ___
> >>> Emc-users mailing list
> >>> Emc-users@lists.sourceforge.net
> >>> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>>
> >> 
> >> --
> >> Check out the vibrant tech community on one of the world's most
> >> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> >> ___
> >> Emc-users mailing list
> >> Emc-users@lists.sourceforge.net
> >> https://lists.sourceforge.net/lists/listinfo/emc-users
> >>
> >
> > 
> > --
> > Check out the vibra

Re: [Emc-users] 240V single phase input vfd

[John Figie]

All,

Thanks for your replies.

My real question was to see if anyone had used GOHZ or some other cheap
drive.  I currently run all my machines from a home made rotary phase
converter.  It works pretty well but does not produce the best 3 phase.
Yes I know you can use capacitors to adjust the outputs which I have.  The
rotary converter has been running in my shop for about 15 years. I have a
hydraulic automatic surface grinder that does n't like being run from the
phase converter.  The pump motor overheats when run from my rotary
converter, I think maybe this is because the motor runs near full load.

I know I can use a larger drive and derate it to use on single phase power,
but that seems like a much more expensive option. Some drives have missing
phase detection that I could probably trick with some kind of AC input. I
think the concerns for me are that the input diode bridge will see the
input current distributed among 4 diodes but instead of 6.  Also the
conduction angle of the diodes will be longer since all of the input
current must be supplied from the single phase rather than overlapping
phases. Finally the stress on the DC bus capacitors will be much higher due
to the higher DC bus ripple. This bus capacitor RMS ripple current degrades
the capacitors due to internal heating.

Now since this is a lathe spindle and I am a hobbyist how often will I
really need to load the machine to 5hp? Probably not very often. Also I can
set the acceleration/deceleration to a conservative value to reduce the
peak currents.  Additionally I think I could replace my rotary phase
converter (which is kind of noisy) with the VFD which will produce a
different kind of noise (electrical) but It will be quiet.

My motivation for asking about GOHZ is that I just discovered them and they
have a $294 drive rated for single phase input so I would presume that the
additional stress was considered in the design.

Automation direct does not list any VFDs of 5hp or higher rated for
operation from a single phase.

Here is what I have found so far listed on a spreadsheet.
https://docs.google.com/spreadsheets/d/1YS-QKbJIlBYDSPdWAelA6ZF0zbS30HrHnqE02-opSRI/edit?usp=sharing

If anyone knows of other options please let me know.

John Figie

On Mon, Jan 1, 2018 at 11:09 AM, Dave Cole  wrote:

> I have heard that sometimes you can get around that by putting  a motor
> run capacitor between one of the live phases and the unconnected input
> power terminal.
> That can sometimes trick the drive into thinking that it has power at all
> of the terminals.
>
> Back when VFDs were very expensive the way to do this was with a static or
> rotary phase converter.
> I have a 5 hp 3 phase motor on an old turret lathe spindle that I run off
> a rotary phase converter that I put together a long time ago.It
> works.   You can find how to instructions on how to build one on the
> net.You will need a 3 to 10 hp 3 phase motor as a base device for the
> converter.
>
> You can also make a static 3 phase adapter for your existing motor simply
> by adding some capacitors to "power" the third phase.  Info for that is
> also on the net.
>
> Dave
>
>
> On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:
>
>> Usually there is a diode rectifier at the input but I guess they also
>> measure voltage and refuse to run then to low so experience is important.
>>
>> On Sun, 31 Dec 2017 18:45:44 -0600
>> John Figie  wrote:
>>
>> I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
>>> only have single phase 240V power.  It seems that most 5 hp vfds do not
>>> allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
>>> Does anyone have experience with GOHZ or other affordable 5 hp drives
>>> that
>>> will run on single phase?
>>>
>>> John Figie
>>> 
>>> --
>>> Check out the vibrant tech community on one of the world's most
>>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>>> ___
>>> Emc-users mailing list
>>> Emc-users@lists.sourceforge.net
>>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>>
>> 
>> --
>> Check out the vibrant tech community on one of the world's most
>> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
>> ___
>> Emc-users mailing list
>> Emc-users@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/emc-users
>>
>
> 
> --
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>
---

Re: [Emc-users] 240V single phase input vfd

[Dave Cole]

I have heard that sometimes you can get around that by putting  a motor 
run capacitor between one of the live phases and the unconnected input 
power terminal.
That can sometimes trick the drive into thinking that it has power at 
all of the terminals.


Back when VFDs were very expensive the way to do this was with a static 
or rotary phase converter.
I have a 5 hp 3 phase motor on an old turret lathe spindle that I run 
off a rotary phase converter that I put together a long time ago.    It 
works.   You can find how to instructions on how to build one on the 
net.    You will need a 3 to 10 hp 3 phase motor as a base device for 
the converter.


You can also make a static 3 phase adapter for your existing motor 
simply by adding some capacitors to "power" the third phase.  Info for 
that is also on the net.


Dave

On 1/1/2018 3:46 AM, Nicklas Karlsson wrote:

Usually there is a diode rectifier at the input but I guess they also measure 
voltage and refuse to run then to low so experience is important.

On Sun, 31 Dec 2017 18:45:44 -0600
John Figie  wrote:


I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
only have single phase 240V power.  It seems that most 5 hp vfds do not
allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
Does anyone have experience with GOHZ or other affordable 5 hp drives that
will run on single phase?

John Figie
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Re: [Emc-users] 240V single phase input vfd

[Nicklas Karlsson]

Usually there is a diode rectifier at the input but I guess they also measure 
voltage and refuse to run then to low so experience is important.

On Sun, 31 Dec 2017 18:45:44 -0600
John Figie  wrote:

> I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
> only have single phase 240V power.  It seems that most 5 hp vfds do not
> allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
> Does anyone have experience with GOHZ or other affordable 5 hp drives that
> will run on single phase?
> 
> John Figie
> --
> Check out the vibrant tech community on one of the world's most
> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users

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Re: [Emc-users] 240V single phase input vfd

[Gene Heskett]

On Sunday 31 December 2017 19:45:44 John Figie wrote:

> I have a 5 hp 240V 3 phase induction motor that is for a lathe
> spindle.  I only have single phase 240V power.

1, here in the us, 240 will actually measure about 254 as its 2 legs of 
nominally 127 volts.

2, most vfd's are if derated, tolerant of single phase power, and are 
often labeled for both uses. But because that seriously ups the AC 
currents flowing in its input AC to DC convertors, it can effect the 
life of those parts, so expect to have to replace then at scheduled 
intervals for best dependability.

Your 5 hp will need its 7.5 rated vfd to have its own circuit, which will 
need to be wired in 8ga range wire or bigger, and a correspondingly big 
circuit breaker.  Possibly a 40 amp breaker. I have a 1.5 horse rated 
vfd, running a 1 hp 3 phase motor 230 volt motor on a 10 gauge circuit 
with a dual linked 20 amp breaker, and have had no nuisance trips, or 
complaints from the vfd even under locked rotor conditions.

YMMV of course, but these should be a decent starting point. I don't have 
a power switch for it, but use a couple 40 amp rated SSR's driven from 
the pi that runs the lathe when LinuxCNC has been enabled. That brings 
up all motor power at the same time and has been working well for about 
a year.

> It seems that most 5 
> hp vfds do not allow single phase input.  I found this: 
> http://www.gohz.com/5hp-vfd Does anyone have experience with GOHZ or
> other affordable 5 hp drives that will run on single phase?

See above, and look for a 7.5 hp rated vfd. It should/will be far more 
dependable when fed with single phase power.
>
> John Figie
> --
> Check out the vibrant tech community on one of the world's
> most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
> ___
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] 240V single phase input vfd

[Jon Elson]

On 12/31/2017 06:45 PM, John Figie wrote:

I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
only have single phase 240V power.  It seems that most 5 hp vfds do not
allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
Does anyone have experience with GOHZ or other affordable 5 hp drives that
will run on single phase?


Many "3-phase only" VFDs will run off single-phase power.  
It is best to derate the HP, so maybe use a 7.5 - 10 HP
VFD for a 5 HP motor.  I am using two 3-phase only VFDs here 
in my shop on 240 V single-phase power, and have been doing 
so for many years.  (But, there are a few units that will 
detect the missing phase.)


Jon

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[Emc-users] 240V single phase input vfd

[John Figie]

I have a 5 hp 240V 3 phase induction motor that is for a lathe spindle.  I
only have single phase 240V power.  It seems that most 5 hp vfds do not
allow single phase input.  I found this:  http://www.gohz.com/5hp-vfd
Does anyone have experience with GOHZ or other affordable 5 hp drives that
will run on single phase?

John Figie
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