Re: Thruster Construction

[Subscuba@aol.com]

Rickoshea,

I'm interested in your problem with your circuit breakers blowing. Do you know
if the motors are series wound or shunt wound. Both at turn on, when the
armature is not turning, draw a surge of current. This surge could be what's
tripping the circuit breakers. Have you tried bringing the motors up to speed
at lower voltages and then while the motor is running apply the 36 volts? This
would reduce the surge when the 36 volts is applied, assuming you can sequence
your solenoids fast enough. I assume the circuit breakers are correctly chosen
for steady state current, but it sounds like they may not be rated for the
surge.

Anyway, good luck. It sounds like you have a fast Sub.  Especially if you can
get all 25 horses going. That would be a  total draw on your batteries of
about 563 amps, an appreciable current.

I considered using oil on my batteries also but found Absorbed Glass Mat lead
acid instead. I was worried about acid getting into the oil during charging
and oil getting on the battery plates. My Sub can invert. The oil technique
has a long history and has been sucessful. Can you tell me where I can find
the Woods Hole study on the batteries? I've looked at the Alvin reports.

Have fun,

Ken Martindale