On Monday 04 April 2016 09:37:08 Nicklas Karlsson wrote:
> > Maybe. OTOH, I can probably knock up something in eagle or geda/pcb,
> > and carve it on my machine by the time UPS could make a drop here.
> > Those pictured boards Farnell shows me are quite simple, and adding
> > another thru-hole fo
> Maybe. OTOH, I can probably knock up something in eagle or geda/pcb, and
> carve it on my machine by the time UPS could make a drop here. Those
> pictured boards Farnell shows me are quite simple, and adding another
> thru-hole for the supply bypassing those chips ought to have would be
> ea
On Monday 04 April 2016 01:52:42 Nicklas Karlsson wrote:
> > > > > ISO7421
> > > >
> > > > Now thats sweet, and a heck of a lot better thought out than the
> > > > last such chip I looked at a decade ago. Needs a 4 wire cable
> > > > from each direction, but I don't see as that as a problem other
Lemme clarify- whether or not you're galvanically isolating, any RS485
transceiver needs either 3-wire or 4-wire logic due to its half-duplex
nature, OR to be protocol-aware.
I don't know if the RTS could be used that way. RTS is hardware flow
control, which is obsolete now and often not imple
> That's a bare unidirectional isolator. OK for RS232. Problem being,
> Modbus is over RS422/RS485, a bidirectional protocol and there's a lot
> of difficult problems in creating buffers of any sort. It doesn't know
> which direction it's supposed to drive at any given time.
>
> http://www.mo
That's a bare unidirectional isolator. OK for RS232. Problem being,
Modbus is over RS422/RS485, a bidirectional protocol and there's a lot
of difficult problems in creating buffers of any sort. It doesn't know
which direction it's supposed to drive at any given time.
http://www.mouser.com/Sea
> > > > ISO7421
> > >
> > > Now thats sweet, and a heck of a lot better thought out than the
> > > last such chip I looked at a decade ago. Needs a 4 wire cable from
> > > each direction, but I don't see as that as a problem other than
> > > stealing the ground and 3.3 or 5 volts to run its side
On Sunday 03 April 2016 18:12:28 Nicklas Karlsson wrote:
> > > ISO7421
> >
> > Now thats sweet, and a heck of a lot better thought out than the
> > last such chip I looked at a decade ago. Needs a 4 wire cable from
> > each direction, but I don't see as that as a problem other than
> > stealing t
> > ISO7421
>
> Now thats sweet, and a heck of a lot better thought out than the last
> such chip I looked at a decade ago. Needs a 4 wire cable from each
> direction, but I don't see as that as a problem other than stealing the
> ground and 3.3 or 5 volts to run its side of it at both ends.
On Sunday 03 April 2016 15:07:59 Nicklas Karlsson wrote:
> ISO7421
Now thats sweet, and a heck of a lot better thought out than the last
such chip I looked at a decade ago. Needs a 4 wire cable from each
direction, but I don't see as that as a problem other than stealing the
ground and 3.3 o
ISO7421 is two channel bidirectional, there are more of them with different
configurations.
On Sun, 3 Apr 2016 14:30:50 -0400
Gene Heskett wrote:
> On Sunday 03 April 2016 14:10:04 Nicklas Karlsson wrote:
>
> > I tried opto isolators and they did not work without errors while
> > capacitive i
On Sunday 03 April 2016 14:10:04 Nicklas Karlsson wrote:
> I tried opto isolators and they did not work without errors while
> capacitive insulation barriers did. It was a suprise and I can't tell
> why. I think most devices including opto have a limited dv/dt
> tolerance.
Damn, old wet ram strik
On Sunday 03 April 2016 13:36:23 Danny Miller wrote:
> Well, if you have 2 differential wires with a simple optoisolator at
> the far end, ground noise/ground loops would have no effect
> whatsoever. You don't need a ground. There would be no place to put a
> ground. There are no common-mode iss
I tried opto isolators and they did not work without errors while capacitive
insulation barriers did. It was a suprise and I can't tell why. I think most
devices including opto have a limited dv/dt tolerance.
On Sun, 3 Apr 2016 12:36:23 -0500
Danny Miller wrote:
> Well, if you have 2 differe
On Sunday 03 April 2016 09:35:04 Nicklas Karlsson wrote:
[huge snip]
> You could also read if there is something in the manual about a
> shielded cable and how it should be connected.
>
>
> Nicklas Karlsson
Such information is not mentioned in my Chinglish manual. And thats
troublesome too IMO
Well, if you have 2 differential wires with a simple optoisolator at the
far end, ground noise/ground loops would have no effect whatsoever. You
don't need a ground. There would be no place to put a ground. There are
no common-mode issues. The slave device's ground could be +300VDC above
the
> > Gene Heskett wrote:
> > > On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote:
> > > > > I had SERIOUS problems with my X200 VFD and RS485 bus- I
> > > > > "mostly" fixed it.
> > > > >
> > > > > Here's the thing- yes, RS485 is differential, but the VFD is
> > > > > probably NOT opto-isol
On Sunday 03 April 2016 06:21:38 Nicklas Karlsson wrote:
> On Sat, 2 Apr 2016 11:34:25 -0400
>
> Gene Heskett wrote:
> > On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote:
> > > > I had SERIOUS problems with my X200 VFD and RS485 bus- I
> > > > "mostly" fixed it.
> > > >
> > > > Here's th
On Sat, 2 Apr 2016 11:34:25 -0400
Gene Heskett wrote:
> On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote:
>
> > > I had SERIOUS problems with my X200 VFD and RS485 bus- I "mostly"
> > > fixed it.
> > >
> > > Here's the thing- yes, RS485 is differential, but the VFD is
> > > probably NOT
On Saturday 02 April 2016 07:04:14 Nicklas Karlsson wrote:
> > I had SERIOUS problems with my X200 VFD and RS485 bus- I "mostly"
> > fixed it.
> >
> > Here's the thing- yes, RS485 is differential, but the VFD is
> > probably NOT opto-isolated input. Differential conveys strong noise
> > immunity-
> I had SERIOUS problems with my X200 VFD and RS485 bus- I "mostly" fixed it.
>
> Here's the thing- yes, RS485 is differential, but the VFD is probably
> NOT opto-isolated input. Differential conveys strong noise immunity-
> but ONLY when both A and B wires' voltages are within the input range
I had SERIOUS problems with my X200 VFD and RS485 bus- I "mostly" fixed it.
Here's the thing- yes, RS485 is differential, but the VFD is probably
NOT opto-isolated input. Differential conveys strong noise immunity-
but ONLY when both A and B wires' voltages are within the input range of
the VF
On Friday 01 April 2016 17:17:16 John Thornton wrote:
> You're going to turn copper to steel?
>
Puzzled me too John, until I remembered the date. Today I don't believe
a thing I read, and only about 5% of what I see.
> On 4/1/2016 3:57 PM, Nicklas Karlsson wrote:
> >> On 1 April 2016 at 20:07,
I can turn gold to lead, do you want see. It should have been that kind of
steal.
> You're going to turn copper to steel?
>
> On 4/1/2016 3:57 PM, Nicklas Karlsson wrote:
> >> On 1 April 2016 at 20:07, Dave Cole wrote:
> >>> Profibus is basically an RS485 network as well.I have no idea why
On 4/1/2016 1:48 PM, andy pugh wrote:
> On 1 April 2016 at 20:07, Dave Cole wrote:
>> Profibus is basically an RS485 network as well.I have no idea why
>> they used a purple jacket color.
> There is an awful lot of purple wiring on the London Underground.
> Perhaps that is data cable.
Siemens
You're going to turn copper to steel?
On 4/1/2016 3:57 PM, Nicklas Karlsson wrote:
>> On 1 April 2016 at 20:07, Dave Cole wrote:
>>> Profibus is basically an RS485 network as well.I have no idea why
>>> they used a purple jacket color.
>> There is an awful lot of purple wiring on the London U
> On 1 April 2016 at 20:07, Dave Cole wrote:
> > Profibus is basically an RS485 network as well.I have no idea why
> > they used a purple jacket color.
>
> There is an awful lot of purple wiring on the London Underground.
> Perhaps that is data cable.
What do you plan to do with it? Steel it
On Friday 01 April 2016 13:58:55 Stephen Dubovsky wrote:
> You can not include the termination or pull up/down resistors on a
> RS422/485 network in the drivers (unless they can by disabled.) You
> don't know where (or how many) are located on the bus. They are
> multi-drop networks after all.
Well that is true. It does tend to stand out from the generic gray
control cabling.
Dave
On 4/1/2016 1:26 PM, Peter Blodow wrote:
> ... because this will be different from all other kinds of cables.
> Imagine large facilities, dozens of buildings, with thousands of devices
> being controlled b
On 1 April 2016 at 20:07, Dave Cole wrote:
> Profibus is basically an RS485 network as well.I have no idea why
> they used a purple jacket color.
There is an awful lot of purple wiring on the London Underground.
Perhaps that is data cable.
--
atp
"A motorcycle is a bicycle with a pandemoniu
... because this will be different from all other kinds of cables.
Imagine large facilities, dozens of buildings, with thousands of devices
being controlled by a central control room, wired by random cable
colours. These are being mixed with current supply, LAN, telephone and
all other cables t
On 4/1/2016 11:55 AM, andy pugh wrote:
> On 1 April 2016 at 18:33, Dave Cole wrote:
>> Unless you are running at 60+ Kbaud and up and long distances you likely
>> won't need anything but twisted pair cabling.
> It was mainly the purple thing.
Ha ha...
Well, I must like purple also.I have the
Yes termination with pull up/down in both ends.
On Fri, 1 Apr 2016 13:58:55 -0400
Stephen Dubovsky wrote:
> You can not include the termination or pull up/down resistors on a
> RS422/485 network in the drivers (unless they can by disabled.) You don't
> know where (or how many) are located on t
You can not include the termination or pull up/down resistors on a
RS422/485 network in the drivers (unless they can by disabled.) You don't
know where (or how many) are located on the bus. They are multi-drop
networks after all. Only terminate the two far ends.
On Fri, Apr 1, 2016 at 1:37 PM,
> > > Twisted pair is a transmission line and subject to all the vagaries
> > > of load matching and such.
> > >
> > > That cables impedance is not listed there,
> >
> > Yes it is. 120 Ohms.
>
> Resistance is NOT impedance, Andy. And I first read that as 1200 because
> my screen is high res and
On 1 April 2016 at 16:58, John Dammeyer wrote:
> Which cable is the Van Damme?
> Can you post an ebay # or link?
http://www.ebay.co.uk/itm/141838984494
--
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lun
On Friday 01 April 2016 11:33:18 andy pugh wrote:
> On 1 April 2016 at 16:22, Gene Heskett wrote:
> >> http://www.rapidonline.com/cables-connectors/belden-9841-data-cable
> >>-for-rs-485-51-6887
> >
> > Twisted pair is a transmission line and subject to all the vagaries
> > of load matching and s
On 1 April 2016 at 18:33, Dave Cole wrote:
> Unless you are running at 60+ Kbaud and up and long distances you likely
> won't need anything but twisted pair cabling.
It was mainly the purple thing.
--
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial
On 4/1/2016 10:33 AM, andy pugh wrote:
> On 1 April 2016 at 16:22, Gene Heskett wrote:
>>> http://www.rapidonline.com/cables-connectors/belden-9841-data-cable-for-rs-485-51-6887
>> Twisted pair is a transmission line and subject to all the vagaries of
>> load matching and such.
>>
>> That cables i
Which cable is the Van Damme?
Can you post an ebay # or link?
Thanks
John
> -Original Message-
> From: andy pugh [mailto:bodge...@gmail.com]
> Sent: April-01-16 8:33 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Modbus wiring
>
> On 1 Apri
On 1 April 2016 at 16:22, Gene Heskett wrote:
>> http://www.rapidonline.com/cables-connectors/belden-9841-data-cable-for-rs-485-51-6887
>
> Twisted pair is a transmission line and subject to all the vagaries of
> load matching and such.
>
> That cables impedance is not listed there,
Yes it is. 12
On Friday 01 April 2016 07:02:14 andy pugh wrote:
> On 1 April 2016 at 11:46, Erik Christiansen
wrote:
> > Incidentally, is that cable in the last picture twisted pair?
> > Shielded or no, is its characteristic impedance controlled?
>
> It is just what I cold find in Maplin that evening.
> I wil
On Friday 01 April 2016 06:46:02 Erik Christiansen wrote:
> On 30.03.16 17:13, andy pugh wrote:
> > In the end, I fitted a different VFD which has a pre-written HAL
> > driver. It also only has two connections for RS485, so is less
> > confusing. I found a way to connect the dongle to the motherbo
On 1 April 2016 at 11:46, Erik Christiansen wrote:
>
> Incidentally, is that cable in the last picture twisted pair? Shielded
> or no, is its characteristic impedance controlled?
It is just what I cold find in Maplin that evening.
I will see how well it works, and if there is a problem I can buy
On 30.03.16 17:13, andy pugh wrote:
> In the end, I fitted a different VFD which has a pre-written HAL driver.
> It also only has two connections for RS485, so is less confusing.
> I found a way to connect the dongle to the motherboard header:
> https://forum.linuxcnc.org/forum/18-computer/30675-on
On 9 February 2016 at 11:23, andy pugh wrote:
> This is where things get iffy. Imagine that I have the 2-terminal
> dongle plugged into a laptop. What do I use for a gnd? Stuff a wire
> down the side of the USB connector? trap the wire in the hinge? :-)
In the end, I fitted a different VFD which
On 09.02.16 11:23, andy pugh wrote:
> On 9 February 2016 at 09:10, Erik Christiansen
> wrote:
> > The two-terminal dongle would be used for half-duplex, with separate
> > grounds, relying on less than 7v float.
>
> This is where things get iffy. Imagine that I have the 2-terminal
> dongle plugge
On 08/02/16 13:16, andy pugh wrote:
> Is that ever going to work? The YSB dongle seems deficient in
> terminals by at least 1, possibly 4...
The quick answer here is YES the dongle is deficient in that it should
provide at least a screen connection rather than just data. The adapter
I use with the
On 9 February 2016 at 09:10, Erik Christiansen wrote:
> The two-terminal dongle would be used for half-duplex, with separate
> grounds, relying on less than 7v float.
This is where things get iffy. Imagine that I have the 2-terminal
dongle plugged into a laptop. What do I use for a gnd? Stuff a w
On 9 February 2016 at 09:10, Erik Christiansen wrote:
> What about 20 mA current loop? Sending an analogue signal as a current,
> rather than a voltage is reputed to be significantly more noise immune
> than sending it as a voltage.
I have a 7i49 with 6 channels of +/- 10V for servo drives that I
On 08.02.16 13:16, andy pugh wrote:
> I need to connect to 8P8C connector on the VFD which has pins
> 1 A'
> 2 B'
> 3 A'
> 4 R
> 5 D
> 6 B'
> 7 DP5V
> 8 SG(GND)
>
> Is that ever going to work? The YSB dongle seems deficient in
> terminals by at least 1, possibly 4...
The above looks a lot like fu
On 09/02/16 05:20, Kirk Wallace wrote:
> (Bottom of page here:
> http://wiki.linuxcnc.org/cgi-bin/wiki.pl?AVR
> has it been five years already?)
Sounds about right ... must get some of these longer term projects
finished ;) That includes a nice modbus module for additional inputs and
control ...
--
From: "andy pugh"
To: "Enhanced Machine Controller (EMC)"
Sent: Monday, February 8, 2016 7:22:17 PM
Subject: Re: [Emc-users] Modbus wiring
On 8 February 2016 at 23:10, Bertho Stultiens wrote:
> I'd start with writing the manufacturer for the right docs.
I tri
On 02/08/2016 12:54 PM, andy pugh wrote:
> On 8 February 2016 at 20:34, Bertho Stultiens wrote:
>> But, I should not hijack the thread with information theory...
>
> In theory Modbus should be better, but I don't have any information
> about the VFD interface.
>
> That's the version of information
On 2/8/2016 3:54 PM, andy pugh wrote:
> On 8 February 2016 at 20:34, Bertho Stultiens wrote:
>> But, I should not hijack the thread with information theory...
> In theory Modbus should be better, but I don't have any information
> about the VFD interface.
>
> That's the version of information theo
On 8 February 2016 at 23:10, Bertho Stultiens wrote:
> I'd start with writing the manufacturer for the right docs.
I tried.
http://www.lovatoelectric.co.uk/Information-request/cnt
Appears to have a "Send" button that doesn't do anything.
--
atp
If you can't fix it, you don't own it.
http://www.
On 8 February 2016 at 23:10, Bertho Stultiens wrote:
>> I thought of that, but they only document writable parameters. None of
>> them look like a likely place to read currents or voltages.
>
> Often you have r/w registers, where you read a measured value and write
> a parameter. However, you are
On 2/8/2016 1:03 PM, Bertho Stultiens wrote:
> Telephony has been digitalized completely today. Television has
> transitioned from analog to digital, freeing more than 50% of the
> bandwidth, while increasing the number of channels. Radio will follow
> (currently running parallel).
There have bee
Andy,
This isn't the worst thing I've seen. Rs485 is a two wire differential half
duplex signalling system. The doc says that it can run up to 38.4kbps.
So you one 1 wire to the plus of the master and the vfd and the other wire
to the minus. It will run on anything twisted that is better than tin
On 02/08/2016 11:56 PM, andy pugh wrote:
>> My best guess is that they have mapped the entire register space from
>> the front-panel config (page 4-9 and forward), as documented, to the
>> communications register map. That should be possible to test with a few
>> read commands.
>
> I thought of th
On 8 February 2016 at 22:20, Bertho Stultiens wrote:
> My best guess is that they have mapped the entire register space from
> the front-panel config (page 4-9 and forward), as documented, to the
> communications register map. That should be possible to test with a few
> read commands.
I thought
On 02/08/2016 11:03 PM, andy pugh wrote:
>> Try and try again, or get a hold of the documentation. ;-)
>
> The documentation is silent on the subject:
> http://www.lovatoelectric.com/Single-phase-supply-200-240VAC-50-60Hz-EMC-suppressor-built-in-PNP-24VDC-programmable-inputs/150005010/spd
Interes
On 8 February 2016 at 21:42, Bertho Stultiens wrote:
> Try and try again, or get a hold of the documentation. ;-)
The documentation is silent on the subject:
http://www.lovatoelectric.com/Single-phase-supply-200-240VAC-50-60Hz-EMC-suppressor-built-in-PNP-24VDC-programmable-inputs/150005010/spd
On 02/08/2016 10:12 PM, andy pugh wrote:
>> I thought that ModBus was pretty standardized:
> So which register do I write to to set output frequency?
Do you have the original documentation of the VFD? I guess not.
Do you have any "old" VFD control or test software, If you have, you can
reverse eng
On 8 February 2016 at 21:04, Bertho Stultiens wrote:
> I thought that ModBus was pretty standardized:
So which register do I write to to set output frequency?
Which register do I read to monitor motor current?
(And, back to the original question, how do I wire the 8 pins on the
VFD to the 2 pi
On 02/08/2016 09:54 PM, andy pugh wrote:
> On 8 February 2016 at 20:34, Bertho Stultiens wrote:
>> But, I should not hijack the thread with information theory...
> In theory Modbus should be better, but I don't have any information
> about the VFD interface.
>
> That's the version of information
On 8 February 2016 at 20:34, Bertho Stultiens wrote:
> But, I should not hijack the thread with information theory...
In theory Modbus should be better, but I don't have any information
about the VFD interface.
That's the version of information theory that matters to me here.
--
atp
If you can
On 02/08/2016 09:12 PM, Peter C. Wallace wrote:
>> The number of bits required goes to the root of Shannon's information
>> theory. We see how effective it is in our daily life everywhere and it
>> is better than analog.
>>
>> Telephony has been digitalized completely today. Television has
>> trans
> On 02/08/2016 08:52 PM, Nicklas Karlsson wrote:
> >> Noise in analog will reduce the effective resolution, whereas noise in
> >> digital can be easily filtered and the resolution stays constant.
> >> Analog signals cannot be isolated easily and trying so results in
> >> awkward non-linearities th
On 02/08/2016 09:01 PM, Nicklas Karlsson wrote:
>> I agree with the sentiment that it is less than ideal to have something
>> that certainly has a local microprocessor that then creates an analog out
>> which you then read in. It's a lossy channel and subject to any number of
>> problems. That assu
On Mon, 8 Feb 2016, Bertho Stultiens wrote:
> Date: Mon, 8 Feb 2016 21:03:44 +0100
> From: Bertho Stultiens
> Reply-To: "Enhanced Machine Controller (EMC)"
>
> To: "Enhanced Machine Controller (EMC)"
> Subject: Re: [Emc-users] Modbus wiring
>
&
On 02/08/2016 08:23 PM, Jerry Scharf wrote:
> I agree with the sentiment that it is less than ideal to have something
> that certainly has a local microprocessor that then creates an analog out
> which you then read in. It's a lossy channel and subject to any number of
> problems. That assumes you
On 02/08/2016 08:52 PM, Nicklas Karlsson wrote:
>> Noise in analog will reduce the effective resolution, whereas noise in
>> digital can be easily filtered and the resolution stays constant.
>> Analog signals cannot be isolated easily and trying so results in
>> awkward non-linearities that need to
On Mon, 8 Feb 2016 11:23:23 -0800
Jerry Scharf wrote:
> Bertho,
>
> I agree with the sentiment that it is less than ideal to have something
> that certainly has a local microprocessor that then creates an analog out
> which you then read in. It's a lossy channel and subject to any number of
> pr
> On 02/08/2016 07:01 PM, Dave Cole wrote:
> >>> RS485 is two wire, half duplex.
> >>> I think you have a RS422 connection that can run full duplex.
> >>> I don't recognize the D and R pins??Perhaps Data Ready and Request
> >>> to Send ??
> >>> Those aren't normally required for RS422.
> >> I a
Bertho,
I agree with the sentiment that it is less than ideal to have something
that certainly has a local microprocessor that then creates an analog out
which you then read in. It's a lossy channel and subject to any number of
problems. That assumes you have the software skills and documentation
On 02/08/2016 07:01 PM, Dave Cole wrote:
>>> RS485 is two wire, half duplex.
>>> I think you have a RS422 connection that can run full duplex.
>>> I don't recognize the D and R pins??Perhaps Data Ready and Request
>>> to Send ??
>>> Those aren't normally required for RS422.
>> I am becoming inc
> On 8 February 2016 at 17:40, Dave Cole wrote:
> > RS485 is two wire, half duplex.
> > I think you have a RS422 connection that can run full duplex.
> > I don't recognize the D and R pins??Perhaps Data Ready and Request
> > to Send ??
> > Those aren't normally required for RS422.
>
> I am be
On 2/8/2016 12:51 PM, andy pugh wrote:
> On 8 February 2016 at 17:40, Dave Cole wrote:
>> RS485 is two wire, half duplex.
>> I think you have a RS422 connection that can run full duplex.
>> I don't recognize the D and R pins??Perhaps Data Ready and Request
>> to Send ??
>> Those aren't normall
On 8 February 2016 at 17:40, Dave Cole wrote:
> RS485 is two wire, half duplex.
> I think you have a RS422 connection that can run full duplex.
> I don't recognize the D and R pins??Perhaps Data Ready and Request
> to Send ??
> Those aren't normally required for RS422.
I am becoming increasin
RS485 is two wire, half duplex.
I think you have a RS422 connection that can run full duplex.
I don't recognize the D and R pins??Perhaps Data Ready and Request
to Send ??
Those aren't normally required for RS422.
Dave
On 2/8/2016 8:16 AM, andy pugh wrote:
> I am tempted to attempt to contro
yea it's a bit short on pins
i use these
http://www.ebay.co.uk/itm/Useful-80mm-USB-2-0-to-RS-485-RS-422-Serial-Converter-Adapter-Cable-ST-/151912461839
On 8 February 2016 at 13:16, andy pugh wrote:
> I am tempted to attempt to control the lathe VFD with Modbus.
>
> I have one of these:
>
> ht
I am tempted to attempt to control the lathe VFD with Modbus.
I have one of these:
http://www.ebay.com/itm/CH340-USB-to-RS485-485-Converter-Adapter-Module-For-Win7-Linux-XP-Vista-/201258967189?hash=item2edbf82095:g:SDAAAOSw2s1UrPYd
I need to connect to 8P8C connector on the VFD which has pins
1 A
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