(ET) Rewiring the shunt

[Chris Zach <czach computer org>]

In other news, I am getting a bit tired of the tractor slowing down so 
much in D1 and D2, even with FW disabled. So I took apart the shunt 
wires and rewired it.

Now the main power wires are right on either side of the shunt strip. 
This should make for less resistance in the bolts there and hopefully 
less heating. Nope, that copper shunt gets very hot anyway. Something's 
wrong with it.

For now I have bypassed it with a small length of 8 gauge wire. Now it's 
cool, tractor runs better. One other thing I have noticed: When the 
batteries are low flooring it in D1 and D2 causes the motor to drop out. 
I couldn't figure out why but I think it's because the voltage sag at 
the batteries is high enough that the relays drop out from undervoltage. 
Nice Elec-trak "feature" (sort of)

Chris