T-Pain Is On A Boat: Re: [Electric Boats] The Project and some questions

Thursday, October 31, 2013

Re: [Electric Boats] The Project and some questions

1 hp = 746 watts = 62 amps at 12 volts. That's a lot of current but not that much power. That's why drive systems usually are higher voltage, 48 v being the most common.

The direct answer on your charger question is yes, connect the charger to the battery bank and plug it into the generator. You can run the motor and charger at the same time. The battery will see the difference between input from the charger and output to the motor. Practically though, you will need a big (expensive) charger to even put 30 amps into the battery bank.

Note when calculating range you ought not drain the battery down more than 50% very often.

On Wednesday, October 30, 2013, wrote:

Okay, some of this is going to seem incredibly stupid, but I'm rather new at some of this and am having trouble getting answers I can understand.

We're in the middle of building an electric pontoon boat with a sternwheel as a driver. The motor is a permanent magnet, series wound dc motor (12v) geared down1/148 and with an output at the shaft of 1hp (or so they tell me). At present I have a bank of 35AH deep cycle batteries comprising 280 ah, with 200 watts of solar and a 30 amp charge controller. That set up on its own should get several hours of power at full tilt, but that's not my question.

Occasionally, we'll need to run the thing for longer than the battery capacity. I have a small 1000W generator aboard. Here's the question: can I use the genny and a charger to direct drive the motor? Can I use the genny and the charger connected to the battery bank while the motor is running to extend the range? What are the implications for the motor and batteries? How big a charger would I need to act as a high amperage power supply for the motor without frying either?

As another note, i have a pulse modulated speed controller available for the motor that will handle 100A if needed.

anyone? anyone?