EV Digest 5082
Topics covered in this issue include:
1) power steering
by mike golub <[EMAIL PROTECTED]>
2) RE: Neg supply for E-meter
by Cor van de Water <[EMAIL PROTECTED]>
3) Re: Pack voltage switches for peripheral devices?
by "John Luck Home" <[EMAIL PROTECTED]>
4) Re: Motor Question
by Jim Husted <[EMAIL PROTECTED]>
5) Re: power steering
by Bob Bath <[EMAIL PROTECTED]>
6) Re: New NEDRA Voltage Divisions
by "Roderick Wilde" <[EMAIL PROTECTED]>
7) Gliders
by Rush <[EMAIL PROTECTED]>
8) Re: Gliders
by "Bob Rice" <[EMAIL PROTECTED]>
9) Re: Listed by anyone on the EVDL?
by "Bob Rice" <[EMAIL PROTECTED]>
10) Re: TEST for turn off digest mode
by "damon henry" <[EMAIL PROTECTED]>
11) RE: Mk3 Regs
by "Myles Twete" <[EMAIL PROTECTED]>
12) RE: Neg supply for E-meter
by "Myles Twete" <[EMAIL PROTECTED]>
13) RE: Neg supply for E-meter
by "Don Cameron" <[EMAIL PROTECTED]>
14) Re: Pack voltage switches for peripheral devices?
by Lee Hart <[EMAIL PROTECTED]>
15) RE: Neg supply for E-meter
by "Roger Stockton" <[EMAIL PROTECTED]>
16) RE: Mk3 Regs
by "Roger Stockton" <[EMAIL PROTECTED]>
17) Re: I want to build a PWM DC motor controller
by Lee Hart <[EMAIL PROTECTED]>
18) Re: Motor Question
by "Stefan T. Peters" <[EMAIL PROTECTED]>
19) RE: Neg supply for E-meter
by "damon henry" <[EMAIL PROTECTED]>
20) RE: Neg supply for E-meter
by "Don Cameron" <[EMAIL PROTECTED]>
21) RE: Neg supply for E-meter
by Cor van de Water <[EMAIL PROTECTED]>
22) Re: Motor Question
by Jim Husted <[EMAIL PROTECTED]>
--- Begin Message ---
In general when the power steering is disconnected
what options do you have when you don't install a
replacement battery powered pump or do some sort of
belt connection?
1-Do you have to reconnect a different box?
2-Can you just disconnect the two hoses to the power
steering, and just let them drain out?
Thanks
Mike
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--- Begin Message ---
Interesting data point:
I tried a handful of "switching" power supplies on 70V DC
(all were spec'ed between 100 and 240V AC) and half of them
did supply output power at such low input voltage!
NOTE that you will have to cut the max output power at least
in half, because the input voltage is half, so the input
current is double the usual - you don't want to blow a fuse
or switching transistor...
No guarantees, but I certainly would give a surplus laptop
or other isolated switching DC supply a test on 70V DC, see
if it can power a small 12V (or whatever the output voltage)
load and MEASURE the output it supplies, then check and see
if the E-meter is happy....
Regards,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-501-641-8576
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of STEVE CLUNN
Sent: Tuesday, January 10, 2006 9:51 PM
To: [email protected]
Subject: Re: Neg supply for E-meter
I wasn't to clear , my mower set up is with 12v orbitals so with a 400 amp
curtis , it dose have some power , for a lawn mower. . I wasn't talking
about the voltage sense , just powering the meter ,( but somthing would have
to be done for this to ) I was thinking that the transistor and resistor
would be in oppisite places as you described so the resistor would pass the
same current as the meter and zenor would split the current with the meter ,
and protect the meter from going over set voltage .
all in all , its probable best to buy some power supply to get the isolation
, and not take a chance .
steve clunn 4
----- Original Message -----
From: "Cor van de Water" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, January 10, 2006 8:50 PM
Subject: RE: Neg supply for E-meter
> Sounds like either:
> - voltage divider, feeding a follower transistor which can withstand 120V.
> The current through the resistors should be low, under 5mA. The transistor
> carries the same current as the E-meter and dissipates between 50 and 90V
> at that current.
> If the max current of the E-meter is 100mA, the transistor will take
> up to 9W, much more than Lee's solution but likely cheaper.
> - big zener diode + resistor.
> The resistor will need to carry MORE current than the E-meter ever draws,
> so this is even less efficient, likely you will dissipate 20W continuous
> and you will need a zener that can handle up to 200mA at 15V or more,
> so a 3+ Watt zener. This is a rather crude solution....
>
> BTW if your pack is 96V (8x12?) how can your min voltage be 70?
> I would think you need to keep it over 1.75 - 1.67V per cell, so
> about 80 - 84V?
>
> Regards,
>
> Cor van de Water
> Systems Architect
> Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
> Skype: cor_van_de_water IM: [EMAIL PROTECTED]
> Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
> Fax: +1 408 731 3675 eFAX: +31-87-784-1130
> Proxim Wireless Networks eFAX: +1-501-641-8576
> Take your network further http://www.proxim.com
>
>
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> Behalf Of STEVE CLUNN
> Sent: Tuesday, January 10, 2006 5:01 AM
> To: [email protected]
> Subject: Re: Neg supply for E-meter
>
>
> I kind of have the same problem you do , with my e mower , pack voltage is
> 96v , and I have no 12v alx battery . I was thinking , e meter takes 80 ma
> max , min pack voltage will be 70 , max voltage to meter 35v , so to power
> the meter off traction pack , I could have a 400 ohm resistor ( 10 watts
> min) for the traction pack + going to the meter b+ , at the meter b+ have
> a
> regulator to ground to keep the meter b+ for going over 35v . The
> regulator
> would have to pass at least 250 ma to deal with 120v battery charge
> voltage
>
> and e meter in sleep mode using just 20 ma.
> steve clunn 3
> ----- Original Message -----
> From: "damon henry" <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Monday, January 09, 2006 1:50 PM
> Subject: RE: Neg supply for E-meter
>
>
>> Actually, there is very little wiring on the motorcycle and most of it I
>> have replaced already. If it weren't for the way the dumb lights are
>> made, I could easily isolate my whole 12volt system from the frame.
>> Unfortunately all the lights mounting hardware is built expecting the
>> negative side of the power equation from the frame, so even if I ran a
>> seperate ground wire to each, I would also have to figure out a way to
>> isolate the individual hardware piece from the frame. That is just not
>> worth the effort...
>>
>> damon
>>
>>
>>>From: Mike & Paula Willmon <[EMAIL PROTECTED]>
>>>Reply-To: [email protected]
>>>To: [email protected]
>>>Subject: RE: Neg supply for E-meter
>>>Date: Mon, 09 Jan 2006 00:45:34 -0900
>>>
>>>Not to change the subject from the E-meter problem but 10 of those babies
>>>would give the requisite 30A at 12V (nominal) to run an accessory system.
>>>Keep 'em cool enough, the input wires protected and you wouldn't have to
>>>worry about isolating their chassis' from your frame ground. Throw a
>>>Trace
>>>(now Xantrex)C-40 charge controller inline and there's an inexpensive
>>>alternatve to DC-DC converters. More versatile too.
>>>
>>>Mike
>>>
>>>-----Original Message-----
>>>From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
>>>Behalf Of Cor van de Water
>>>Sent: Sunday, January 08, 2006 1:09 AM
>>>To: [email protected]
>>>Subject: RE: Neg supply for E-meter
>>>
>>>
>>>I suggest to look at (used) laptop power supplies.
>>>They are always switchers (you can use them from
>>>100 - 240V AC, so they should be fine up to 360V
>>>DC, which limits the voltage (during eq charge)
>>>to about 22 x 12V batteries or 264V system.
>>>They have plenty of output current (3+ Amp) and
>>>often deliver around 15 - 18V.
>>>
>>>One currently on Ebay for $5 +$8 shipping:
>>>Item nr 6837357331
>>>
>>>You can still look in your junk-box for old
>>>power supplies - make sure they have a wide
>>>input voltage range.
>>>
>>>Success,
>>>
>>>Cor van de Water
>>>Systems Architect
>>>Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
>>>Skype: cor_van_de_water IM: [EMAIL PROTECTED]
>>>Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
>>>Fax: +1 408 731 3675 eFAX: +31-87-784-1130
>>>Proxim Wireless Networks eFAX: +1-501-641-8576
>>>Take your network further http://www.proxim.com
>>>
>>>
>>>-----Original Message-----
>>>From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
>>>Behalf Of Rush
>>>Sent: Saturday, January 07, 2006 2:40 PM
>>>To: [email protected]
>>>Subject: Re: Neg supply for E-meter
>>>
>>>
>>>Lee,
>>>
>>>Would this one work - http://datasheet.astrodyne.com/PWB.pdf
>>>
>>>Model AFC-15S, output V- 15vdc, output A - 0.66, output W - 10W, input
>>>V -
>>>85-265vac?
>>>
>>>sorta pricy, $39 from them.
>>>
>>>Thanks
>>>
>>>Rush
>>>Tucson AZ
>>>www.ironandwood.org
>>>
>>>
>>>----- Original Message -----
>>>From: "Lee Hart" <[EMAIL PROTECTED]>
>>>To: <[email protected]>
>>>Sent: Saturday, January 07, 2006 12:29 PM
>>>Subject: Re: Neg supply for E-meter
>>>
>>>
>>> > From: damon henry
>>> >> I still have a couple more questions specific to my application. I
>>>don't
>>> >> currently have an accesory battery, just a DC-DC converter. The
>>>negative
>>> >> side of my DC-DC is connected to my frame. The E-meter manual states
>>> >> that I must connect pin one to both the negative side of my traction
>>>pack
>>> >> as well as the negative supply for the E-meter. This of course
>>> >> connects
>>> >> the negative side of my traction pack to the negative side of my
>>> >> DC-DC
>>> >> and my frame. This sounds bad...
>>> >
>>> > Correct! You can't power the E-meter directly from your 12v accessory
>>>power.
>>> >
>>> >>The manual offers two options...
>>> >
>>> > There is another option, which I prefer. Get a small switching power
>>>supply
>>> > that can run directly off your traction pack, and which has an
>>> > isolated
>>>12v
>>> > output to power the E-meter (and nothing else). The E-meter takes so
>>>little
>>> > power that this can be a "wall wart" or old laptop power brick. Just
>>>make
>>> > sure it is a SWITCHING power supply, not one with a 60hz transformer!
>>> >
>>> > Almost all low-power switchers have "universal" inputs and work on AC
>>> > or
>>> > DC, at anything from 90-300v. For example, I use an Astrodyne 15vdc
>>> > 0.5amp switcher. It is rated for 90-264vac input, but actually works
>>>from
>>> > 60-350vdc. It's a little potted "brick", and would even work
>>> > underwater.
>>> >
>>> > The advantage of this approach is that the little switcher is more
>>>efficient
>>> > than having to run the main DC/DC just to power a *second* DC/DC to
>>> > get
>>> > the 25ma or so the E-meter needs. The Astrodyne I use draws 4-9ma from
>>> > my 132v propulsion pack, depending on whether the E-meter is asleep or
>>>in
>>> > full sunlight. A normal "full-size" DC/DC would draw over 20ma even
>>> > with
>>>NO
>>> > load on its output.
>>> > --
>>> > Lee Hart
>>> >
>>> >
>>> >
>>>
>>
>>
>
>
--- End Message ---
--- Begin Message ---
Tried the snubber and the diode across 3 sets of contacts in one relay today
and it was greatly improved although still some arcing.
After about 10 on/off cycles the contacts welded shut . so back to the
drawing board :-(
I was thinking of using the Infeon
http://pdf.alldatasheet.co.kr/datasheet-pdf/view/80054/INFINEON/SPP11N60S5.html
Cool MOS SPP11N60S5 rated at 500volts 11amps to turn off the heater before
opening the relay contacts. This would give me a redundant safe(ish) method
of isolating the heater and only switching the relay at zero amps.
However (& isnt there always a however...) it seems I would need to tie my
aux 12v supply negative to the traction pack negative and I do not want to
do this I want to keep the traction pack isolated from vehicle ground.
Are there any electronic guru's who could suggest a way of switching on
the MOSFET safely using the existing switched 12volt relay that operates
the blower motor.
Thanks
John
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, January 10, 2006 5:26 PM
Subject: Re: Pack voltage switches for peripheral devices?
John Luck Home wrote:
Thanks Lee - I think the 10 Ohm and the 1uF are in series with each
other
then across the contacts.
Correct.
As I am going to be breaking 10 amps should I increase to say 20ohm and
4.7uF? Is it CxR seconds that I am trying to make large?
It takes about 1 msec for the contact to go from its closed to its fully
open
position. The value of C is to limit the rate of rise in voltage when the
switch contact opens. This C is being charged by you load current, so it
needs to go up proportionately as the load current increases.
The R is there for two reasons. First, it limits the peak current when the
contact closes (and has to both power the load *and* discharge the
capacitor). Second, it provides damping to prevent oscillations and
ringing
if the load is inductive.
If the R and C values get unreasonable, you can add a diode across the R.
Orient it to conduct when the capacitor is charging (i.e. it shorts the
R). C
can now be smaller, and R larger.
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 [EMAIL PROTECTED]
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--- End Message ---
--- Begin Message ---
Hey Stephan
Do to the brush tension you shouldn't really be able to spin these motor by
hand very good. They shouldn't spin like an AC motor would. They should just
stop as soon as you quit turning it. If yours is spinning real easy then you
might have dry bearings (no grease left) and or worn brushes that are not
getting good spring tension. If your motor stops as soon as you quit turning
it (by hand) that is a good sign usually. If you have a vid camera and want to
take a short clip I'd be happy to look at it to see what "rustling" noise you
may be talking about.
Hope this helps
Jim Husted
Hi-Torque Electric
Stefan Peters <[EMAIL PROTECTED]> wrote:
I have my eBay Prestolite MKH4002 pump motor cleaned up and nicely
mounted to it's current home, the "gogo-kart". Tried a single twelve
volt battery straight to the terminals today (had to make it move, it
was just killing me sitting there on the shop floor) - my that's alot of
torque for such a little vehicle... nice and smooth ramp-up though.
Anyways, the motor makes a gentle "rustling" sound while running at
those moderate RPMs. I am a little concerned about the bearings. Is it
supposed to freewheel when turned by hand with nothing attached? Or just
turn easily but quickly (not suddenly) stop when you stop spinning it?
---------------------------------
Yahoo! Photos
Ring in the New Year with Photo Calendars. Add photos, events, holidays,
whatever.
--- End Message ---
--- Begin Message ---
You don't want to leave in the same rack. The
gearings (leverage) will be different. In the case
of my Civic, the hatch has manual, the sedan (200 lbs.
heavier) has power. I swapped in the manual, and life
is just fine. I'm 163 lbs, and the wife is 130, but
no problems parallel parking, esp. with tires inflated
to 42 PSI.
--- mike golub <[EMAIL PROTECTED]> wrote:
> In general when the power steering is disconnected
> what options do you have when you don't install a
> replacement battery powered pump or do some sort of
> belt connection?
>
> 1-Do you have to reconnect a different box?
>
> 2-Can you just disconnect the two hoses to the power
> steering, and just let them drain out?
>
> Thanks
>
> Mike
>
> __________________________________________________
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> Tired of spam? Yahoo! Mail has the best spam
> protection around
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>
>
'92 Honda Civic sedan, 144V (video or DVD available)!
www.budget.net/~bbath/CivicWithACord.html
____
__/__|__\ __
=D-------/ - - \
'O'-----'O'-'
Would you still drive your car if the tailpipe came out of the steering wheel?
Are you saving any gas for your kids?
__________________________________________________
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--- End Message ---
--- Begin Message ---
Victor, the future of EV racing was most definitely a major consideration
when setting up these new voltage divisions. The new system allows for
expanded high voltage classes. Thanks for your input and concern.
Roderick Wilde
NEDRA Rules Committee
----- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, January 10, 2006 10:58 PM
Subject: Re: New NEDRA Voltage Divisions
Rod,
When AC machines (typically hi voltage will enter the scene, there is
a bit shortage of "A"s as you said. Current inverters run at 380V max
and next step up is 650VDC inverters - performance will be very different
and yet they both fall to the same A3 class "348V and above".
Do we care how much "above"?
I suppose this can be addressed later...
Whatever you guys decide please leave room to made additions and
corrections later (perhaps without disturbing already established
classes). Just a thought ahead of time.
Victor
Roderick Wilde wrote:
Don't freak out just yet by the title. All we did was start making new
classes for higher voltage cars. We came to the realization that cars
were climbing in voltage and there was a big difference between a 241 and
348. Kind of like over 100 volts. We had first toyed with calling the two
new divisions AA and AAA but came to the additional realization that we
may run out of As someday as voltages get higher and we need more
divisions. This idea also goes along with wire gauge sizing, the littler
the number the bigger the wire (the lower the letter in the alphabet, the
higher the voltage) until they got to 0/0 then it started going back up;
1/0, 2/0, 3/0, 4/0 etc. See what I mean, 2A, 3A, 4A, 5A, etc. Using A's
we run out of space eventually when we get to the AAAAAA voltage
division. For slang puposes you can still tell people you are running
double A division or triple A division. I hope most of you can accept all
these changes in your life at one time :-)
Roderick Wilde
NEDRA Rules Committee
A3 348V and above
A2 301V-347V
A 241V -300V
B 193V - 240V
C 169V - 192V
D 145V - 168V
E 121V - 144V
F 97V - 120V
G 73V - 96V
H 49V - 72V
I 25V - 48V
J 24V and below
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--- End Message ---
--- Begin Message ---
HI all,
Tonight on the NBC nightly news there will be a piece about that new Chinese
car that will sell for under $10,000. Maybe that is a good place to start for a
glider.
Rush
Tucson AZ
www.ironandwood.org
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "Rush" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Wednesday, January 11, 2006 11:00 AM
Subject: Gliders
> HI all,
>
> Tonight on the NBC nightly news there will be a piece about that new
Chinese car that will sell for under $10,000. Maybe that is a good place to
start for a glider.
>
> Rush
> Tucson AZ
> www.ironandwood.org
>
Hi All;
Saw a good article in yesterdaze NY Times. A Chinese out fit has a car
at Detroit, to show the world, They aim to come in at 10 grand, too.
Different than the "Cherry "one that is SUPOSED to go on sale here soon.
AFTER they get it to meet USA crash tests? Well, we ,USA , laffed at the
"Toyopets" and VW Beetles when they first hit these shores.Gees! Will they
sell them at Wal*Mart?<g>!
Chinese Auto folks might offer cars as AS BUILT Electrics, too. Hope
so.
Seeya at BBB
Bob
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: "EV Discussion List" <[email protected]>
Sent: Wednesday, January 11, 2006 12:08 AM
Subject: Listed by anyone on the EVDL?
> Pay a buck to find http://www.myersmotors.com/?
>
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5655015913
>
Gees! Theres a sucker born EVery minute<g>! Gotta admire his gall!Ain't
GOOGLE a great thing, or EVen Yahoo?
Seeya
Bob
--- End Message ---
--- Begin Message ---
Digest mode does not affect the emails you send, it just sends you digests
rather than individual emails. I believe there is a setting in the
mailserver that automatically switches you to digest mode if it gets a
certain number of bounced emails back from you. This could happen if your
email is full, or your ISP has a temporary problem.
From: "STEVE CLUNN" <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: <[email protected]>
Subject: Re: TEST for turn off digest mode
Date: Sat, 7 Jan 2006 22:02:52 -0500
how do to test for this , most of my post arn't going through , . steve
clunn
----- Original Message ----- From: "Joe Smalley" <[EMAIL PROTECTED]>
To: "EV discussion list" <[email protected]>
Sent: Saturday, January 07, 2006 7:21 PM
Subject: TEST for turn off digest mode
Someone set my mail setting to digest yesterday.
This is a test to see if it got changed back.
--- End Message ---
--- Begin Message ---
> You could be right... I think the price feels really high
> because you and I know it can be done for so much less.
Perhaps. More likely the price feels high because it is a substantial
fraction of the cost of a battery.
--- End Message ---
--- Begin Message ---
> Keep in mind that this may be OK for **your** EMeter, but has failed with
others.
Is that the confirmed Root Cause or a guess?
My boat with 36v pack has had an emeter now for some 3 years.
I tap at the 24v point as recommended in the Xantrex manual.
I've NEVER had a power problem with either of the 2 emeters I used.
Initially I used an older non-Xantrex EMETER w/o serial port---no problems.
Eventually I sold the emeter to friend and I upgraded to a Xantrex Link10.
During this time I've also disconnected the entire pack at least once while
having the boat out of water.
Without evidence of root cause on the returned meters you mention, the cause
could well have been something entirely different than the tapped pack. A
loose power connection or failure to connect the wires up in the proper
sequence (also a very much known cause of failure) seems more likely to me
given my experience with 2 meters.
I took the suggestion by fellow listers to avoid these problems: I wired a
connector to the harness and installed a connector header to the back of the
emeter. Once it's right, it stays right unless a connection fails. Then
EVERY TIME you mess with the pack wiring, remove the connector plug. When
done, reinstall the plug.
Q: Has anyone who's using such a connector ever had a failed emeter?
-Myles Twete
http://www.austinev.org/evalbum/492.html
--- End Message ---
--- Begin Message ---
Not a guess. If you read my two other notes: this was confirmed by the tech
at Xantrex.
I do not understand the pushback on this. Again, a few people have had this
problem, and the tech at Xantrex confirms it.
Why bother tapping the pack and risking the hassle of getting the thing
fixed if a $10 miniature DC-DC is a reasonable precaution? Seems silly to
me.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Myles Twete
Sent: January 11, 2006 9:32 AM
To: [email protected]
Subject: RE: Neg supply for E-meter
> Keep in mind that this may be OK for **your** EMeter, but has failed
> with
others.
Is that the confirmed Root Cause or a guess?
My boat with 36v pack has had an emeter now for some 3 years.
I tap at the 24v point as recommended in the Xantrex manual.
I've NEVER had a power problem with either of the 2 emeters I used.
Initially I used an older non-Xantrex EMETER w/o serial port---no problems.
Eventually I sold the emeter to friend and I upgraded to a Xantrex Link10.
During this time I've also disconnected the entire pack at least once while
having the boat out of water.
Without evidence of root cause on the returned meters you mention, the cause
could well have been something entirely different than the tapped pack. A
loose power connection or failure to connect the wires up in the proper
sequence (also a very much known cause of failure) seems more likely to me
given my experience with 2 meters.
I took the suggestion by fellow listers to avoid these problems: I wired a
connector to the harness and installed a connector header to the back of the
emeter. Once it's right, it stays right unless a connection fails. Then
EVERY TIME you mess with the pack wiring, remove the connector plug. When
done, reinstall the plug.
Q: Has anyone who's using such a connector ever had a failed emeter?
-Myles Twete
http://www.austinev.org/evalbum/492.html
--- End Message ---
--- Begin Message ---
From: John Luck Home
> Tried the snubber and the diode across 3 sets of contacts in one relay today
> and it was greatly improved although still some arcing. After about 10 on/off
> cycles the contacts welded shut, so back to the drawing board :-(
Remind me again; what voltage and current are you trying to switch? And what
were the ratings of the contacts you tried in series, and the snubber part
values?
Also, I'm not sure what your goal is. You can buy off-the-shelf relays
(mechanical
and solid state) that will safely switch your heater. What was the reason for
wanting
to build something yourself?
> I was thinking of using the Infeon Cool MOS SPP11N60S5 rated at 500volts
> 11amps to turn off the heater before opening the relay contacts. This would
> give
> me a redundant safe(ish) method of isolating the heater and only switching the
> relay at zero amps.
A redundant circuit requires that *either* the MOSFET or the relay can safely
turn
off the load all by itself. If the relay can't safely break the load by itself,
then don't use it.
>Are there any electronic guru's who could suggest a way of switching on
>the MOSFET safely using the existing switched 12volt relay that operates
>the blower motor.
What you are describing is a "solid state relay". There are dozens of circuits
for them,
and many commercial products. They usually use an optocoupler.
--- End Message ---
--- Begin Message ---
Don Cameron [mailto:[EMAIL PROTECTED] wrote:
> Not a guess. If you read my two other notes: this was
> confirmed by the tech at Xantrex.
What a tech tells the user does not necessarily have to be accurate.
The tech could be new to servicing this product and/or have poor
understanding of the root cause of the problem, or he could know very
well what the problem is and feed you a line anyway.
> I do not understand the pushback on this. Again, a few people
> have had this problem, and the tech at Xantrex confirms it.
A few people claim to have let their meter's smoke out by supplying the
E-Meter with supply voltage near/at the maximum that the manual claims
the meter can handle; this is different from letting it out due to
tapping the pack.
There is *no* electrical reason for tapping the pack to cause any
problem at all. The meter internally connects the supply negative and
traction pack negative, so even using a DC/DC converter is electrically
the same as tapping the pack, unless you tap the pack improperly. That
is, tapping the pack such that the E-Meter's supply negative is not at
the same potential as the traction pack negative, such as would happen
if you tapped off across any group of batteries in the string that does
not include the most negative battery.
Tapping the pack at 12V to supply the meter will *not* harm it, but the
meter may shut down if the supply voltage browns out when the battery
sags under heavy load. Tapping the pack at 18V or 24V will eliminate
the brownout concern and keeps the supply voltage well away from the
potential danger zone of 35-40V even at the peak of the charge cycle.
Tap the pack at 30-36V at your own risk; it is not the fact that you are
supplying the meter from a tap that is the issue, but rather than the
voltage during charge *might* exceed what the meter can survive.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Chris Brune [mailto:[EMAIL PROTECTED] wrote:
> You could be right... I think the price feels really high
> because you and I know it can be done for so much less.
I think this is it precisely.
> If
> only you and I could get our companies to play in the
> hobbyist market...or I need a lot more spare time.
Yeah, you and me both! ;^>
> But I
> think Rich has done a great job with the PFC Chargers. He
> seems to be selling quite a few at a price I would have never
> thought possible, and I think that's great. For those who
> really want the features that these offer, I bet people will
> be willing to pay. I think this is espicially true if we get
> some great feedback from the initial users.
Yes, absolutely! For those who need the functionality, it is a steal at
twice the price. My gut feeling is that those who need the reg function
will continue buying the $45 Mk2 and only those who really lust for
data, etc. will spring for a $75 unit.
> How does EVILbus support 99 nodes???? I thought the hardware
> limited the number of nodes to around 32.
It doesn't, although my understanding is that it is a sliding scale and
the number fo nodes increases as the baud rate decreases. 32 nodes at
9600baud might just correspond to about 99 at 2400baud. But my guess is
that the regs continue to use Rich's 5-wire analog REGBUS to daisychain
them together and connect to the PFCxx charger, and the "bridge" is
really a REGBUS to EvilBus bridge that translates the various conditions
signalled on the analog REGBUS into EvilBus messages.
Of course, it could be the opposite, with the regs daisychained using
EvilBus and then an EvilBus to REGBUS bridge connecting them to the
PFCxx, but this seems a bit of an odd arrangement (forcing every PFCxx
customer to spend an additional $75 in order to connect the Mk3 regs to
their charger).
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Rod Hower wrote:
>> I think the term that best applies here is 'Kluge'.
From: Stefan Peters
>Hey now. I'm definitely not trying to throw together parts to create a
>makeshift controller. It's quite a bit more systematic and nit-picky
>than that.
Stefan, you should look up the word "Kluge". It is not a derrogative
term, and I think you will agree that it describes what you are doing.
A "kluge" is a complicated solution to a simple problem that nevertheless
works very well. It comes from the Kluge printing presses, which were
fantastically complicated but very high quality. Competitors used it as a
term of derision, but users loved them because they worked so well.
The extra complexity was a sort of "belts and suspendors" design so it
could keep working despite problems.
A modern PWM controller is kind of a kluge, too. Instead of one big power
transistor, most use dozens of cheap little ones. This makes it far harder
to design and build. But it works if you get all the details right. (And if you
don't, it all collapses like a house of cards!).
I do think that your controller strategy is going in the wrong direction
(extra complications; will just lead to higher cost and lower reliability).
But, I can't tell if there is any "light at the end of the tunnel" that may
justify it in the end. For all I know, maybe it *is* possible to use dozens
of cheap little controllers instead of one big one, and come out ahead
in the long run. So, best of luck with it! I'll provide whatever advice I can.
--- End Message ---
--- Begin Message ---
Jim Husted wrote:
Hey Stephan
Do to the brush tension you shouldn't really be able to spin these motor by hand very good. They shouldn't spin like an AC motor would. They should just stop as soon as you quit turning it. If yours is spinning real easy then you might have dry bearings (no grease left) and or worn brushes that are not getting good spring tension. If your motor stops as soon as you quit turning it (by hand) that is a good sign usually. If you have a vid camera and want to take a short clip I'd be happy to look at it to see what "rustling" noise you may be talking about.
Thanks!
I likely would have a hard time spinning it by hand if the large pulley
(6") wasn't on it. It stops within a second or less when I let go of the
pulley. The top of the brushes are about even with the top of the brush
holders, with plenty of spring travel left, and every spring has tension
on it and is centered on each brush (the springs look shinier and newer
then the rest of the motor). I sprayed some electrical contact cleaner
on the commuter and checked the black film that came off the brushes as
I turned it slowly (then wiped it off afterwards). It was nice and even
on each brush, so they appear in good condition and making full contact
with the commuter bars.
No video camera (been spending all my extra money on electronic parts).
I will ask around and see if I can get a loaner.
Can I simply repack the bearings? Is there any special procedure or
grease I should use? I have noticed that it takes noticeably more
current to run in one direction then the other (only two terminals).
Which would be the direction that the motor was set to spin from the
factory (less or more)?
--
Stefan T. Peters
--- End Message ---
--- Begin Message ---
I took the suggestion by fellow listers to avoid these problems: I wired a
connector to the harness and installed a connector header to the back of
the
emeter. Once it's right, it stays right unless a connection fails. Then
EVERY TIME you mess with the pack wiring, remove the connector plug. When
done, reinstall the plug.
Q: Has anyone who's using such a connector ever had a failed emeter?
I am setting mine up this way as well, but I believe there is one caveat.
According to a chat I had with John Wayland on Sunday, who always has
several e-meters in use, a common way to blow an e-meter is to disconnect
other wires (I'm not sure which specific one is the culprit, but the HV neg
seems likely) before the High Voltage positive lead. Since the HV+ is fused
he recommended always removing this fuse first when disconnected and
inserting this fuse last when reconnecting. When you pull a connector
header you have no control over which pin disconnects first, and electricity
is very fast. Also this may only apply to higher voltages so might not be a
problem on a 36v system like Myles's boat.
So in addition to using the connector header I am planning on using Johns
HV+ fuse guidelines as well.
damon
--- End Message ---
--- Begin Message ---
We disagree.
People will do what they want. I for one have had the experience and do not
want to repeat it. I will tend to trust the manufacturer's technician over
anecdotal evidence to the contrary.
I am more than happy to have the $10 part to protect the unit even if you or
others think it is a waste of my money.
Don
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Roger Stockton
Sent: January 11, 2006 10:14 AM
To: [email protected]
Subject: RE: Neg supply for E-meter
Don Cameron [mailto:[EMAIL PROTECTED] wrote:
> Not a guess. If you read my two other notes: this was confirmed by the
> tech at Xantrex.
What a tech tells the user does not necessarily have to be accurate.
The tech could be new to servicing this product and/or have poor
understanding of the root cause of the problem, or he could know very well
what the problem is and feed you a line anyway.
> I do not understand the pushback on this. Again, a few people have had
> this problem, and the tech at Xantrex confirms it.
A few people claim to have let their meter's smoke out by supplying the
E-Meter with supply voltage near/at the maximum that the manual claims the
meter can handle; this is different from letting it out due to tapping the
pack.
There is *no* electrical reason for tapping the pack to cause any problem at
all. The meter internally connects the supply negative and traction pack
negative, so even using a DC/DC converter is electrically the same as
tapping the pack, unless you tap the pack improperly. That is, tapping the
pack such that the E-Meter's supply negative is not at the same potential as
the traction pack negative, such as would happen if you tapped off across
any group of batteries in the string that does not include the most negative
battery.
Tapping the pack at 12V to supply the meter will *not* harm it, but the
meter may shut down if the supply voltage browns out when the battery sags
under heavy load. Tapping the pack at 18V or 24V will eliminate the
brownout concern and keeps the supply voltage well away from the potential
danger zone of 35-40V even at the peak of the charge cycle.
Tap the pack at 30-36V at your own risk; it is not the fact that you are
supplying the meter from a tap that is the issue, but rather than the
voltage during charge *might* exceed what the meter can survive.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Roger wrote:
> Tap the pack at 30-36V at your own risk; it is not the fact that you are
> supplying the meter from a tap that is the issue, but rather than the
> voltage during charge *might* exceed what the meter can survive.
Make that "Will" exceed:
36V battery (18 cells) will go over 18 x 2.5 = 45V during charge.
Even a tap at 30V can give you 15 cells x 2.6 = 39V during equalization
which is too close to the max voltage of the E-meter to be safe.
Do take the effort of limiting to around 24V and your E-meter will be
much happier.
Your batteries will be happy if you don't tap, causing imbalance in your
pack.
IMHO the E-meter should include an _isolated_ power supply, it is causing
too much headache and causes for faulty wiring (read: deadly mistakes)
while in the end you need to create a supply anyway. The burden has now
been pushed from equipment maker to user, but the bigger picture does not
change. Only the extra hassle for the user, instead of the ease of use
if this feature was integrated.
I know, I know - cost is an issue for some of us.
Regards,,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-501-641-8576
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Roger Stockton
Sent: Wednesday, January 11, 2006 10:14 AM
To: [email protected]
Subject: RE: Neg supply for E-meter
Don Cameron [mailto:[EMAIL PROTECTED] wrote:
> Not a guess. If you read my two other notes: this was
> confirmed by the tech at Xantrex.
What a tech tells the user does not necessarily have to be accurate.
The tech could be new to servicing this product and/or have poor
understanding of the root cause of the problem, or he could know very
well what the problem is and feed you a line anyway.
> I do not understand the pushback on this. Again, a few people
> have had this problem, and the tech at Xantrex confirms it.
A few people claim to have let their meter's smoke out by supplying the
E-Meter with supply voltage near/at the maximum that the manual claims
the meter can handle; this is different from letting it out due to
tapping the pack.
There is *no* electrical reason for tapping the pack to cause any
problem at all. The meter internally connects the supply negative and
traction pack negative, so even using a DC/DC converter is electrically
the same as tapping the pack, unless you tap the pack improperly. That
is, tapping the pack such that the E-Meter's supply negative is not at
the same potential as the traction pack negative, such as would happen
if you tapped off across any group of batteries in the string that does
not include the most negative battery.
Tapping the pack at 12V to supply the meter will *not* harm it, but the
meter may shut down if the supply voltage browns out when the battery
sags under heavy load. Tapping the pack at 18V or 24V will eliminate
the brownout concern and keeps the supply voltage well away from the
potential danger zone of 35-40V even at the peak of the charge cycle.
Tap the pack at 30-36V at your own risk; it is not the fact that you are
supplying the meter from a tap that is the issue, but rather than the
voltage during charge *might* exceed what the meter can survive.
Cheers,
Roger.
--- End Message ---
--- Begin Message ---
Hey Stefan
Okay I looked up the MKH motor in my Prestolite manual. Although it is
listed as a traction motor it should only be a 2 terminal motor designed to run
CCWDE, that's CCW looking at the drive (non-brush) end. If this is correct as
to what you have then I don't know how you are getting CWDE as the motor is not
set-up to rotate that direction. Furthermore it shouldn't change anything
electrically if Positive was connected to the "A" terminal or to the "F"
terminal. That raises some flags for me as there maybe a short of some kind
that is causing the motor to draw higher current. This is unless you've
disconnect the field jumper connection going to the brush ring. Prestolite
didn't advance these types brush rings as far as I've ever seen. I thought I'd
get you what the manual said this should run so you can compare it to what you
are running. I caution however that the manual has been found to be wrong from
time to time. These specks look correct but this is not a commo!
n motor
to me. Anyway here are the spec's
36 volt 19 amps 3250rpm's 0 Ft. Lbs.
36 volt 175 amps 1880 to 2100 rpm's 17.5 Ft. Lbs.
Keep me posted as now you have perked my curiosity
Hope this helps
Jim Husted
Hi-Torque Electric
---------------------------------
Yahoo! Photos Showcase holiday pictures in hardcover
Photo Books. You design it and well bind it!
--- End Message ---
