(ET) NiCD powered Elec-trak report

[Christopher Zach <czach computer org>]

Just spent the morning with the BB600 powered Elec-trak; thought I would 
pass on the performance statistics.

Tractor: Elec-trak E20 outfitted with 60 30ah rated (ho ho) BB600's in 
two strings of 30 batteries, nominal voltage of 36 volts, 60ah capacity.

Was running the tractor pretty much flat out today mulching leaves and 
using the power sweeper to sweep them up for the back yard. Average 
draws on the pack were in the range of 60-100 amps constant.

At the end of the job the tractor's pack was reading 32 volts, and the 
packs read 34ah and 36ah (dual E-meters and shunts). Performance was 
still fine.

Oh and the temps. I store the tractor outside, it was in the low 20's 
last night, warmed up to the 30's by the time I went outside to do all this.

So in a nutshell, the BB600 based pack with a rated capacity of 60ah was 
putting out 70ah at a draw rate of 1C to 1.5C constant.

By comparison my 52ah 300 volt pack on the Prizm is down to about 15ah 
capacity at 20 degrees before I am scraping the 260's for voltage.

God I love NiCDs. I can't wait for the snow. Though I think I will add a 
 thrid pack of 30 cells for some ballast in the rear and more range. 
Will report on how three strings in parallel share the load.

Chris