Thread: battery voltage
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Dr. Di Dr. Di is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 16
Default battery voltage
On Sat, 8 Mar 2008 04:11:20 -0800 (PST),
wrote:

I am making a B.Tech final year project on Lifting Jacks.On certain
calculations i found that i would need a 6 horsepower.I would like to
know battery specifications for the DC Motor to do so....

You didn't say what voltage you planned on using, but if I assume
you'd like to use 12 volts, your 6hp motor would consume around 400
amps.. It wouldn't be very practical or advisable..

The calculations are simple.. 1 horsepower = 746 watts.. You can
assume roughly a 90% efficiency for a DC motor of 6 hp, so your demand
would be just shy of 5000 watts.. To calculate the amps required for
any given voltage, simply divide the watts required for your
application by the voltage delivered to the motor, and divide that
result by the efficiency of the motor..

Remember also, to delivery 12 volts to a 6 hp motor, you'd need some
very heavy cables...

I doubt if your application would require a constant 6 hp for an
extended time, but if it did, batteries would have to have an
impractical capacity and would likely to be of excessive cost and
weight to sustain your application

hope this helps..

Diana