series or parallel

[michael defrain]

Well the jet drive didn't work well, pulled way to many amps,Hot Hot Hot I'm going with a out drive. major re-construction looking to do it fast would like to run two 4000amp 11.V Lipo. My Castle can handle the volts or the amps whats the best way to go with the batteries parallel or Series. Whats better?? amps or volts running a 2650 castle brushles in a 30"Mono Mamba monster ESC gotta get back in the water

here we go Cut and paste, Little advice?

 

[ron upton]

well series will give you 22 volts and as a rule of thumb that will give you too many rpm for the motor (around 58000rpm) parallel will give you longer run time and about 29000 rpm unloaded

 

[Larry Roberts]

I tryed a jet drive a few years ago and had the same problem, I found the cure was to run a gear reduction off the motor,these units maybe hard to find Mac products may still be around check with Fine Design or run a lower KV motor 1500 or so. Two motor units will only double your headache

 

[Curtis Beaumont]

The question is what was the current draw? From that you may be able to infer where you need to go. I would bring the kv of the motor down if at all possible, but you only have the one motor. Do you have any 4S or 5S batteries lying around to test? A wattmeter would be very helpful and relatively cheap right now. It's hard to know where to go if you don't know where you are.

Good luck,

Curtis

 

[jayt]

The jet drive didn't work because you had the wrong motor for it. Looks like you could be headed in the same direction again if you're not careful. Definately parallel wiring with that motor.

Why chose an "outdrive", the steerable ones are very inefficient. A standard strut or stinger is a far better solution. Start with a prop around an x442 or m445 and see how the boat runs. That ESC is not the strongest......

.

 

[michael defrain]

Jayt... You are right, no I will not be going with an out drive I miss spoke. The stinger is a much better option and adjustable pitch, so I picked up the Ros-Mono speedmaster. As Far as the power source It will be parallel 3s 4000 it's what I use in my truck, so what I have. I need the amps and current not so much the volts. I have a couple grimes prop here not sure how they convert to your recommendations still learning whats good and whats bad so who makes a good ESC?

 

[JimZaremski]

when you parallel batteries, the voltage they give stays the same but you double the current capacity. When you series them, the voltage doubles but the current stays the same. e.g. you have two 12 volt, 20 Amp*hr batteries. connect them in parallel, you have a 12 volt, 40 Amp*hr battery. Connect them in series, you have a 24 volt, 20 Amp*hr battery.

that said, it usually makes sense to go with higher voltage (assuming the equipment can handle it.) If you go for more current you need to up-gauge your wiring and it gets more stressful on the power electronics.