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Discussion Starter #1
Any good sources for meter shunts? What is the typical resistance for a
1000 Amp shunt?

A 1 milliOhm shunt at 1000 Amps will be dissipating 1000 watts! That seems
too high.

So 0.1 milliOhm?? Can a shunt be reasonably made??



Thank you,

Dave Delman
1981 Electric DeLorean Project
electricdelorean.com



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Discussion Starter #2
In a message dated 9/17/2007 8:19:01 PM Central Daylight Time,
[email protected] writes:

Any good sources for meter shunts? What is the typical resistance for a
1000 Amp shunt?

A 1 milliOhm shunt at 1000 Amps will be dissipating 1000 watts! That seems
too high.

So 0.1 milliOhm?? Can a shunt be reasonably made??



Thank you,

Dave Delman
1981 Electric DeLorean Project
electricdelorean.com



A 50mv 1000 amp shunt would be 50 micro Ohms and would dissipate 50 watts at
1000 amps.

A 1000 amp 50 mv shunt is available at EVParts:
(_http://www.evparts.com/shopping/index.php?id=602_ (http://www.evparts.com/shopping/index.php?id=602)
(http://www.evparts.com) ).

Ken




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Discussion Starter #4
On the subject of shunts, can they serve double duty? I have a shunt in line for my eMeter, could
I hook up another device (ammeter) to this without affecting the eMeter?

Dave Cover, stepping forward after my last step back

--- [email protected] wrote:

> In a message dated 9/17/2007 8:19:01 PM Central Daylight Time,
> [email protected] writes:
>
> Any good sources for meter shunts? What is the typical resistance for a
> 1000 Amp shunt?
>
> A 1 milliOhm shunt at 1000 Amps will be dissipating 1000 watts! That seems
> too high.
>
> So 0.1 milliOhm?? Can a shunt be reasonably made??
>
>
>
> Thank you,
>
> Dave Delman
> 1981 Electric DeLorean Project
> electricdelorean.com
>
>
>
> A 50mv 1000 amp shunt would be 50 micro Ohms and would dissipate 50 watts at
> 1000 amps.
>
> A 1000 amp 50 mv shunt is available at EVParts:
> (_http://www.evparts.com/shopping/index.php?id=602_
> (http://www.evparts.com/shopping/index.php?id=602)
> (http://www.evparts.com) ).
>
> Ken
>
>
>
>
> ************************************** See what's new at http://www.aol.com
>
> _______________________________________________
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Discussion Starter #8
.001ohms * 1000A = 1volt That is how you are getting 1000Watts

But most shunts are 50-100mv at full scale so a 1000A shunt is 1000 *
.050 or 1000 * .100 or 50-100W. peak.

You can only put that much thru the shunt for a limited amount of time.
I'd be surprised if you can get 1/2 of that on average
So you are probably only talking 25Watts or less. (Could of just not had
that second helping of cake)

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Discussion Starter #9
"50mV at full scale" is common for shunts... so a 250A shunt is 0.0002
ohms. There are lower resistance shunts still.

In general you should be able to hook up a second device to the same
shunt. Do not splice into the sensing wires, just screw new ones onto
the shunt.

Danny

----- Original Message -----
From: Dave Cover <[email protected]>
Date: Monday, September 17, 2007 9:02 pm
Subject: Re: [EVDL] Shunts
To: Electric Vehicle Discussion List <[email protected]>

> On the subject of shunts, can they serve double duty? I have a
> shunt in line for my eMeter, could
> I hook up another device (ammeter) to this without affecting the
> eMeter?
> Dave Cover, stepping forward after my last step back
>
> --- [email protected] wrote:
>
> > In a message dated 9/17/2007 8:19:01 PM Central Daylight Time,
> > [email protected] writes:
> >
> > Any good sources for meter shunts? What is the typical
> resistance for a
> > 1000 Amp shunt?
> >
> > A 1 milliOhm shunt at 1000 Amps will be dissipating 1000 watts!
> That seems
> > too high.
> >
> > So 0.1 milliOhm?? Can a shunt be reasonably made??
> >
> >
> >
> > Thank you,
> >
> > Dave Delman
> > 1981 Electric DeLorean Project
> > electricdelorean.com
> >
> >
> >
> > A 50mv 1000 amp shunt would be 50 micro Ohms and would dissipate
> 50 watts at
> > 1000 amps.
> >
> > A 1000 amp 50 mv shunt is available at EVParts:
> > (_http://www.evparts.com/shopping/index.php?id=602_
> > (http://www.evparts.com/shopping/index.php?id=602)
> > (http://www.evparts.com) ).
> >
> > Ken
> >
> >
> >
> >
> > ************************************** See what's new at
> http://www.aol.com>
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
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Discussion Starter #10
Hi all,

I have a customer seeking a neat 75mV 500A shunt to replace one he's
not particularly happy with - searching "75mV 500A" on eBay shows you
the sort of shunt he's currently got (big nickel-plated shunts with
black vertical strips, made in China).

He'd prefer something like the Deltec shunts (more compact, with
integrated mounting block) but they only seem to come in 50mV and
100mV. Is anyone aware of any other sources I might be able to look
into? (Preferably just the shunt, since he already has the 75mV 500A
meter to suit.)

TIA,

Ian Hooper
[email protected]

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Discussion Starter #11
they appears on Ebay often, i have purchased mine from here

Philippe


2008/4/28, Ian Hooper <[email protected]>:
>
> Hi all,
>
> I have a customer seeking a neat 75mV 500A shunt to replace one he's
> not particularly happy with - searching "75mV 500A" on eBay shows you
> the sort of shunt he's currently got (big nickel-plated shunts with
> black vertical strips, made in China).
>
> He'd prefer something like the Deltec shunts (more compact, with
> integrated mounting block) but they only seem to come in 50mV and
> 100mV. Is anyone aware of any other sources I might be able to look
> into? (Preferably just the shunt, since he already has the 75mV 500A
> meter to suit.)
>
> TIA,
>
> Ian Hooper
> [email protected]
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>
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Discussion Starter #12
> they appears on Ebay often, i have purchased mine from here
>
> Philippe

If he has one like this:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250241133623
they look neat enough. Would be nice to have a non-conductive block
attached at the bottom for mounting, or how about a clear tube
(http://electroauto.com/catalog/elec.shtml#fuselink) to protect from
contact?

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Discussion Starter #16
Ian Hooper wrote:
> Hi all,
>
> I have a customer seeking a neat 75mV 500A shunt to replace one he's
> not particularly happy with - searching "75mV 500A" on eBay shows you
> the sort of shunt he's currently got (big nickel-plated shunts with
> black vertical strips, made in China).
>
> He'd prefer something like the Deltec shunts (more compact, with
> integrated mounting block) but they only seem to come in 50mV and
> 100mV. Is anyone aware of any other sources I might be able to look
> into? (Preferably just the shunt, since he already has the 75mV 500A
> meter to suit.)

The easiest solution is to get a 100mv shunt, and connect a resistor in
series with the meter to drop the extra 25mv (so he gets 75mv at the meter).

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #17
Along the same vein, I picked up a shunt for the motor side of my
controller, 50mv/1000Amps. I wanted to measure the current my controller
could handle and came across a shunt first. I had been watching for a lon g
time before this option came along. The problem I'm finding is no one makes
a meter to match the shunt.

I've been watching eBay as well as the usual sources; DigiKey, Mouser,
SurplusStore, etc. I just can't find a compatible meter. I'd even go with a
50mv/100A meter, but haven't seen one. It seems all the meters in my range
work at 75mv for the top end.

Since you already have a meter, you know what shunt you need. My problem is
I can't find a meter to match my shunt. Go figure. If I'd have known how
incompatible these can be I wouldn't have jumped on it so quickly.

Dave Cover

Zeke Yewdall <[email protected]> wrote:

> I've only seen ones that are 50mV/500A and 100mV/100A (Occasionally
> 100mV/150A or 50mV/100A). I suppose you could use two of the
> 50mV/500A shunts in series, then put a 3:4 voltage divider on the
> signal to generate the 75mV/500A signal.... sort of clunky though...
>
> Z
>
> On Mon, Apr 28, 2008 at 5:39 AM, vehiculeselectriques.free.fr
> <[email protected]> wrote:
> > Mine is more like this one, though for a 75mV/500A,
> > If your customer is in a hurry, i'm willing to sell it as i never
> ordered
> > the Emeter to use it with, contact me off list
> >
> >
> http://cgi.ebay.com/Blue-Sea-9229-Analog-Meter-Shunt-75A-50mV_W0QQitemZ120231828390QQihZ002QQcategoryZ58049QQrdZ1QQssPageNameZWD1VQQcmdZViewItem
> >
> >
> > philippe
> >
> > 2008/4/28, Ian Hooper <[email protected]>:
> > >
> >
> >
> > > Yeah that's the exact sort he's not happy with - apparently they are
> > > too big, too ugly (roughly finished), and too hard to mount (no
> > > insulating base). He's actually not the first of my customers to
> > > complain about these shunts either, oh well..
> > >
> > > -Ian
> > >
> > > On 28/04/2008, at 6:04 PM, [email protected] wrote:
> > >
> > > >> they appears on Ebay often, i have purchased mine from here
> > > >>
> > > >> Philippe
> > > >
> > > > If he has one like this:
> > > > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250241133623
> > > > they look neat enough. Would be nice to have a non-conductive block
> > > > attached at the bottom for mounting, or how about a clear tube
> > > > (http://electroauto.com/catalog/elec.shtml#fuselink) to protect
> from
> > > > contact?
> > > >
> > > > _______________________________________________
> > > > For subscription options, see
> > > > http://lists.sjsu.edu/mailman/listinfo/ev
> > > >
> > >
> > > _______________________________________________
> > > For subscription options, see
> > > http://lists.sjsu.edu/mailman/listinfo/ev
> > >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
>
> _______________________________________________
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Discussion Starter #18
You could always use a standard 50mV/500A meter, and remember that
it's only reading half of the actual amperage......

Z

dave cover <[email protected]> wrote:
> Along the same vein, I picked up a shunt for the motor side of my
> controller, 50mv/1000Amps. I wanted to measure the current my controller
> could handle and came across a shunt first. I had been watching for a lon g
> time before this option came along. The problem I'm finding is no one makes
> a meter to match the shunt.
>
> I've been watching eBay as well as the usual sources; DigiKey, Mouser,
> SurplusStore, etc. I just can't find a compatible meter. I'd even go with a
> 50mv/100A meter, but haven't seen one. It seems all the meters in my range
> work at 75mv for the top end.
>
> Since you already have a meter, you know what shunt you need. My problem is
> I can't find a meter to match my shunt. Go figure. If I'd have known how
> incompatible these can be I wouldn't have jumped on it so quickly.
>
> Dave Cover
>
>
>
> On Mon, Apr 28, 2008 at 9:18 AM, Zeke Yewdall <[email protected]> wrote:
>
> > I've only seen ones that are 50mV/500A and 100mV/100A (Occasionally
> > 100mV/150A or 50mV/100A). I suppose you could use two of the
> > 50mV/500A shunts in series, then put a 3:4 voltage divider on the
> > signal to generate the 75mV/500A signal.... sort of clunky though...
> >
> > Z
> >
> > On Mon, Apr 28, 2008 at 5:39 AM, vehiculeselectriques.free.fr
> > <[email protected]> wrote:
> > > Mine is more like this one, though for a 75mV/500A,
> > > If your customer is in a hurry, i'm willing to sell it as i never
> > ordered
> > > the Emeter to use it with, contact me off list
> > >
> > >
> > http://cgi.ebay.com/Blue-Sea-9229-Analog-Meter-Shunt-75A-50mV_W0QQitemZ120231828390QQihZ002QQcategoryZ58049QQrdZ1QQssPageNameZWD1VQQcmdZViewItem
> > >
> > >
> > > philippe
> > >
> > > 2008/4/28, Ian Hooper <[email protected]>:
> > > >
> > >
> > >
> > > > Yeah that's the exact sort he's not happy with - apparently they are
> > > > too big, too ugly (roughly finished), and too hard to mount (no
> > > > insulating base). He's actually not the first of my customers to
> > > > complain about these shunts either, oh well..
> > > >
> > > > -Ian
> > > >
> > > > On 28/04/2008, at 6:04 PM, [email protected] wrote:
> > > >
> > > > >> they appears on Ebay often, i have purchased mine from here
> > > > >>
> > > > >> Philippe
> > > > >
> > > > > If he has one like this:
> > > > > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250241133623
> > > > > they look neat enough. Would be nice to have a non-conductive block
> > > > > attached at the bottom for mounting, or how about a clear tube
> > > > > (http://electroauto.com/catalog/elec.shtml#fuselink) to protect
> > from
> > > > > contact?
> > > > >
> > > > > _______________________________________________
> > > > > For subscription options, see
> > > > > http://lists.sjsu.edu/mailman/listinfo/ev
> > > > >
> > > >
> > > > _______________________________________________
> > > > For subscription options, see
> > > > http://lists.sjsu.edu/mailman/listinfo/ev
> > > >
> > > _______________________________________________
> > > For subscription options, see
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> > >
> >
> > _______________________________________________
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> >
> _______________________________________________
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Discussion Starter #19
>
> The easiest solution is to get a 100mv shunt, and connect a resistor in
> series with the meter to drop the extra 25mv (so he gets 75mv at the meter).
>

That's pretty tricky, since you'd have to know exactly how much
current the meter was drawing. I'm not familiar with the particular
one he has, but the ones I've used are very low current -- like
microamps, on the sense inputs. If the meter doesn't have seperate
sense and power inputs, the current draw could be up in the mA range,
but could also vary depending on how many digits of the display are
lit up, which won't work.

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Discussion Starter #20
I think if it is analog Lee 1s correct, 1/3 the resistance of the meter in
series will the meter should do it. It's volts at this point not amps, the
current will be very low. If it is a digital meter then a resistor bridge of
two resistors will do. Something like 100 ohms and 33 ohms in series across
the shunt and then the meter across the 100 ohm resistor.

Mark Grasser


-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of Zeke Yewdall
Sent: Monday, April 28, 2008 11:49 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Shunts

>
> The easiest solution is to get a 100mv shunt, and connect a resistor in
> series with the meter to drop the extra 25mv (so he gets 75mv at the
meter).
>

That's pretty tricky, since you'd have to know exactly how much
current the meter was drawing. I'm not familiar with the particular
one he has, but the ones I've used are very low current -- like
microamps, on the sense inputs. If the meter doesn't have seperate
sense and power inputs, the current draw could be up in the mA range,
but could also vary depending on how many digits of the display are
lit up, which won't work.

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