RE: (ET) Tapping your pack for different battery voltages.

["Elie, Larry (L.D.)" <lelie ford com>]

Well Dwight, using the tiller lift, I have indeed seen the 3 rear lift 
batteries go down faster, very noticeably and measurably faster than the 
other 3.  I never saw it on the mower or blower.  I use it mostly to 
cultivate in sand soil, and do not till very deep.  The load is similar to 
that of the mower in normal grass.  I raise the tiller on either end of a 
180' long row; raising takes probably 30 seconds on a fresh charge and 60 
seconds on a low charge, and the lift fails to lift while the tiller is 
still very much able to till.  In low gear, about 1.5 or 2 mph, that's 
about 132 to 176 feet per minute, so I am using the lift (with tiller on) 
between 20 and 40% of the time.  I have never measured the current on the 
lift, and it may be higher than normal, but it doesn't show on the current 
meter.  That long of a duty cycle is enough that without my equalizer on, 
the 3 batteries in question are .5V lower each than the rest of the pack 
by the time the lift fails to lift.  Gra!
nted, that seems like an enormous amount of charge relative to the other 
batteries, and seems to represent more power than I have a right to 
expect, and my main complaint is not that the tractor is 'dead' (it 
isn't), just that the lift won't work anymore.  My batteries aren't 
matched, so sure, that could be part of the problem, but I am guessing 
anyone else with a tiller has noticed the same thing.  Anyone?

Larry Elie


-----Original Message-----
From: Hazen, Dwight L [mailto:hazen indiana edu]
Sent: Wednesday, October 31, 2001 3:49 PM
To: Elec-Trak
Subject: (ET) Tapping your pack for different battery voltages.




I think we all understand that discharging any cells out or order in our
ElecTrak battery pack is not good for the long term health of the pack. But
I wonder just how much would anyone will use the lift motor? Come on, how
could you get even one amp hour of usage on your 18v tap during one mowing
discharge cycle? The head lights could use about 10 amp hours if you used
the tractor for two hours with the lights on. But this is a 220 amp hour
battery pack that we are tapping into!

I am not sure spending hundreds of dollars to fix this problem is worth it.
If you want to spend money just get all new batteries! You will be
suppressed how much better the tractor will perform. Also rotating your
batteries in the tractor may be a good thing, if not just for the fact that
you will be forced to clean up the connections.

Has everyone noticed how much faster you batteries go down now that cold
weather has arrived and the mowing mulching season is in full swing?
Mulching backwards makes dry leaves disappear! If I need to mulch a big 
pile
I just back into it and raise the back of the deck so the leaves will go
under the deck to meet their fate.  

 Dwight 


Dwight L. Hazen, Indiana University, UITS 
Bloomington, In. 47408-7378 Phone 812-855-5367 hazen indiana edu
http://php.ucs.indiana.edu/~hazen/ Ham Radio wb9tlh arrl net