How many hours from a battery?

[wewak1111]

I'm after some advice, guys, I'm getting about 5 hours continuous use on my 46 lb elect motor, from a 70 a.h. brand new battery.

A mate tells me I should get at least 12 hours...any opinions?

Cheers! :D

[finga64]

what's the maximum drain (or current) drawn by the 'lectric motor??

[wewak1111]

It says in the book "0.28 kwatts"

[finga64]

By my calcs if you run flat maggots all the time is

Motor 0.28kW (ie 280VA) therefore current drawn =280VA/12Volts (assuming the thing is 12 volts as only 1 battery is mentioned)
= 23.333Amps (full load current)

Battery used is a 70Ah so the number of hours to flatten the battery should be:- 70Ah/23.333A = 3 hours

tada..... the answer is if you go flat maggots for 3 hours the battery should be flat.

So the 5 hours you get is a bonus :)

Please, please correct me anyone if I'm wrong as I had to put the thinking cap on and it hasn't been on for over 20 odd years :-/
Had to get the INOX out to stop the squeaks, clunks, bumps and rattles in my head ;)

[wewak1111]

Yep, that was how I figured it, too. I only troll on #3 so that would give the extra time. I'll ask him where he bought his magic battery. :D

[finga64]

the magic battery must be related to my mates father-in-laws beer fridge.
It also doesn't get empty ;D

[ahoj]

you talking about Minn Kota? if so then extra usage is possible because it has Maximiser # 3 will mean 50% 6 hours in that case is very possible and will have some juice left over

Ahoj

[Angla]

The calculations seem right to me. Things that may vary the result would be altering the speed constantly will consume a higher amount. Also stop/start will draw more because of start up currents being probably 3 to 5 times the running current. They don't last long but they will deplete the battery faster.

Angla