[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Front lift and 12-volt batteries

Folks, thanks again for all the generous support and advice.  There were
several thoughtful responses, something to learn from each.  Here's a
synopsis of what I heard, and what happened when I installed the batteries.

tonyascrizzi juno com (TONY B ASCRIZZI) wrote:

> Dave,the 12  volt batteries will work fine.  As far as the lift, I have
> always run mine on 12 volts. I think 18 volts is too high. 

Christopher <Christopher Meier MCI2000 com> wrote:

> I've  been wondering this also. I'd guess that 12v would also make
> it try to draw more current to perform the task, and burn it out.

Larry <lelie ford com> wrote:

> Your idea should work fine but you are right in that the lift is too
wimpy at > 12 V.  I have not tried one at 24 V, and am sure it would not
work for 
> continuous duty.  For light duty, you might get away with it.  Another 
> thought; measure the current for typical lifting.  Compute the 
> equivilant 
> resistance, and add a heavy voltage dropping resistor in series to the
lift to > bring the voltage under load back to 18 or say 21 volts (fully
> batteries are 6.5 to 7.0 V; I'm sure the lift was designed for 3
batteries of > 7 V each).  I suspect you can get away with it.

Walt <dwfh voicenet com> wrote:

> Try looping the strap 2 times. That is to say, instead of only going 
> down to
> the deck, have it loop back to the top of the pulley. this gives a
> advantage and causes the lifting action to go up and down slower.

After these notes, I decided to chance it at 12 volts.  I figured that if
it turned out to be too wimpy, I'd take Larry's advice and add a series
resistor to the 24 volt tap.  I'd also monitor the motor for possible

I found that the lift works a little slowly, but not intolerably so, at 12
volts.  I suspect that when the pack charge begins to get flaky, it might
get to be a problem -- but it's time to stop working then anyway.  I did
not note any funny smells from the lift motor area (just from the traction
motor speed resistors, which were working overtime until I wised up and
shifted to low).

BTW, I used the tractor a little over an hour tonight, and I didn't detect
any decline in performance.  This is with six group 24 Deka Dominator gel
type deep cycle batteries, connected in series-parallel for 36 volts.  They
are rated either 68 or 86 amp hours at the 20 hour rate (I forget which).

I am not using the onboard charger, but rather three external 12v automatic
shutoff chargers, one for each paralleled pair of 12v batteries.  A little
more awkward to connect, but probably better for the Dominators than the
tractor's timer-shutoff charger.  As valve regulated batteries, Dominators
can be damaged by too high a finish rate and/or too long a charge.

Millions of thanks to those who helped out with this question.

     David Roden          THE VIRTUAL PD         roden ald net
     Services for radio broadcasters targeting educated adults
 Programming   Air talent development   Research   Classical music