Amazing to me that the cell installed in reverse hasn't caused other
issues during this time.
Years ago, I installed a PakTrakr monitor on one of my tractors when I
knew I had a sagging pack of lead-acid 6-volters once I had been
running a while, but couldn't find it with a hand held meter by the
time the problem surfaced and I could get off the tractor and start
jabbing at battery terminals.
Anyway, the Paktrakr found it for me, and the drop was hard enough on
that one battery, I decided the aging pack (original with the tractor
I bought used) had done it's time.
I bought a new pack from a known brand and installed it, and left the
PakTrakr in place. Within an hour of operation it flagged a bad
battery and another that was lower then the other four, although the
meter on the ET dash wasn't indicating a big problem. I reported this
to the dealer where I had bought them (special order from an
automotive tire and batteries), and they started the stall tactics.
There isn't much joy in pulling the 66-pounders back out of the ETs,
but I took them back to the dealer after about a week, who couldn't
test them when I arrived. So I left those behind. Later the same day
they called to say the batteries tested perfect. I went back the next
day with my load tester (basic commercial hand held), and tested with
that. First battery went to red immediately. Second went to yellow.
Took the rest of the batteries back and got a refund.
From my perspective, that module level monitoring tool paid for itself
twice in that adventure.
Unfortunately, that product line went out of production many years ago.
Darryl
On 2025-10-31 5:34 p.m., Christopher Zach via Elec-trak wrote:
So about 30 years ago when I first got an Elec-trak I wanted to see
if the lead acid batteries were roughly in sync, or tell when a 6v
battery or cell was hitting zero volts so I could ease off on the
power and bring the tractor in for a charge.
I built a little circuit that used 2 color LEDs (red/green) with a
pair of zener diodes per 12 volt circuit to tell what the battery
voltage was. The code is:
Green: Over 14 volts. Fully charged.
Off: Between 13.8 volts and 10.x volts. Running voltage
Red: Dropping to 10 volts and below.
As a bonus the LEDs would light up brighter as the voltage passed the
setpoints. Thus if a battery was below 10 volts that LED would be
bright while one at 10.4 volts would be dim. Go above 15 volts and
the green LED would turn yellow (bad).
Just dug it out of a box I was cleaning out in the shed and figured
I'd try it on the Elec-trak with the NICD cells. Now the big tractor
has 4 sets of cells in parallel so that won't work well but the
smaller E15's each run with a single string in the front.
Started hooking it up every 10 cells. Dark LED, Bright Red LED, Dark
LED....
Hm. The second set of cells had a voltage imbalance. Got my meter
went from cell to cell then spotted the problem.
Years ago when I replaced this pack I put one of the cells in
backwards. In other words it's been running backwards for at least 5
and maybe 10 years. That resulted in the second set being 1.2 volts
low and thus the red LED.
Pulled the cell and put in a spare that was at 1.0 volts. Light is
out, however when I moved the tractor the middle LED came on (showing
that the second set of 10 batteries has a low cell). Now it's on
charge and in theory all three LEDs should come to a nice green at
the same time.
Kind of amazing this 30 year old thing helped me troubleshoot the
pack like this. I have the cell on my bench, it was empty but not
shorted so I'm charging it at 3.2a rate (at 1.4 volts) and will see
if it's ok. To be honest, it might be fine.....
Chris
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