In a message dated 7/14/01 3:35:03 AM Eastern Daylight Time,
Recovry4x4@aol.com writes:
<< was to mount 2 12 volt
pumps tee'd together on the frame rail. Wiring them in series compensates
for
the voltage difference >>
Au Contraire, mon frere: (that's French for it ain't gonna happen, buddy).
You can put two (similar) light bulbs in series, and they will split the
voltage evenly. If, however, you put two motors in series, even if perfectly
matched in terms of current draw and general condition, one will invariably
start before the other, and what is known as a "chase" condition will occur.
One pump will run very fast, possibly to the point of burning out, and the
other will just sit there and pass current to the other.
At some point, they may even trade places, so to speak, and the running one
will stop, and the stalled one will start. I speak from a position of
humility in this matter, as I once tried to impress a boss of mine with my
electrical prowess, by taking a 12 volt light bar, and putting matched pairs
of lamps and motors in series within the bar, so that it could be used on 24
volts on an M35 that our police dept was using as a dive-team support
vehicle. What a hoot. Half of the rotating lights went so fast you could
barely see them, while their mates just stood still, until the motors started
to burn out.
A simpler expedient is to get a 24 volt pump, or use the center tap between
the batteries to derive the 12 volts.
"Been there, done that, got laughed at" A P Bloom
This archive was generated by hypermail 2b29 : Tue Aug 07 2001 - 09:34:12 PDT