RE: E-meter help (still having trouble)

["Roger Stockton" <rstockton@delta-q.com>]

Hi Paul,

For best results, you need to leave the twisted pair shield disconnected
at the shunt end.  Connect it to ground at the E-Meter.  Above all, do
not terminate it at both ends and do not leave it floating.  Do your
shunt sense wires meet or exceed the E-Meter's recommended minimum
guage?

You might also try disconnecting the shunt wires at the E-Meter and just
connect a jumper in their place.  If the current reading is still
non-zero with the rear contactor energised, the noise isn't getting into
the E-Meter via the shunt wires.

It might also be worth temporarily stringing a dedicated ground lead
from the load side of the shunt up to the pack negative side of the
prescaler (disconnecting the original pack negative connection to the
prescaler, of course!) to see if this helps.  One wouldn't expect a
<0.1V difference to have a large effect, but it seems sensible to try
wiring things by the book first to see if that makes the problem go
away.

Cheers,

Roger.

> -----Original Message-----
> From: owner-ev@listproc.sjsu.edu 
> [mailto:owner-ev@listproc.sjsu.edu] On Behalf Of Paul G
> Sent: November 30, 2001 3:09 PM
> To: ev@listproc.sjsu.edu
> Subject: E-meter help (still having trouble)
> 
> 
> Hi,
> 
> I have replaced the wires from the shunt to the e-meter with 
> a shielded twisted pair. This doesn't affect the result,

[snip]

> I made some attemps to shield between the shunt and contactor 
> while my son watched the e-meter I moved it around, tried 
> hooking it to frame ground, tried hooking it to 120v 
> negative.

[snip]

> P.S. - what would happen if there was a slight (<0.1v) 
> difference between pack negative sense and shunt wires?