Re: (ET) shunt for Alltrax E15 retrofit - what specs, or how to substitute?

[SteveS <ssawtelle fcc net>]

That is true on the E20 - it has a motor current shunt (plate) and an 
ammeter shunt (wire). However, at least on some E12S and E15 models, a 
plate shunt was used for the ammeter. It is also wired differently from 
the E20, appearing at the negative end of the battery pile instead of at 
the positive end. The E12 on the other hand is wired like the E20 - go 
figure....

- SteveS

Chris Zach wrote:

> > The E12S (and E15 too I think) use a piece of copper sheet about an 
> > 1"x3" (I'm guessing here) just about in the middle of the relay area 
> > behind the large panel under the dash. It's set up as a four point 
> > probe - big bolts at each end for power connections with two small 
> > sense connections in between. 
>
>
> I think this is *not* the shunt you're thinking of. The center shunt 
> is used by the field weakening system and shows current draw across 
> the motor armature. When it gets too high, it raises a pair of 
> transistors and shuts down the field weakening resistors.
>
> The ammeter shunt is the length of wire. If you need the size and type 
> I can look it up.
>
> Chris