Battery Cables for Trolling Motor

[blackberg]

I am having a brain fart, and cant compute this anymore, those EE classes in college are blur now.

So, I have 24v trolling motor, bow mount.

Currently, I have 2 of the big marine costco batteries in the front. Last time out last year, have not been out this year ,

I tended to submarine a bit when slowing down, never did it before when the batteries where near the console.
I think 2 batteries, trolling motor and anchor with chain and rode, is just to much weight up front, but my dad wanted to try it his way.

I am thinking of moving the batteries back toward the middle to distribute the weight better, which would mean a about a 12'-14' run of cable.

Also should I run both on one side, or should I see about putting one on either side?

I currently have the console on the right, and a third starting battery, and the pilot, me 99% of the time , weighing at 220ish. On the left side I have the fuel tank, about 15 gallons.

So how thick of a cable should I run? would I be better running two 12v runs or 1 24v run? Sources of cable that wont cost an arm and a leg?

Want to this soon so I can put the underskinning on I bought last year.


thanks

-bb

[HandymanHerb]

How many amps does you TM pull ?

[MH Hawker]

Some thing in a 8 gage should do fine, The older 12 volt 55 pound thrust would draw around 50 amps max and under a 25 foot total run of both wires, 8 gage is whats used. That way what ever you end up using or change to later your in good shape. Especially if your going to under skin.

[HandymanHerb]

That's what I used too, but being an electrician I still like to check amps first

[blackberg]

cant find the specs, but I am assuming its 70-80 amps
mine is just like this
http://www.skifflife.com/306258/minn-ko ... odore-900/
-bb

[HandymanHerb]

I say we be in the 50 amp area, so the #8 would be fine

[blackberg]

I forgot to say, this is a 74# thrust motor,

-bb

[blackberg]

so I should be fine with this then right?
http://shop.genuinedealz.com/Items/Item ... 0BLK%20/ft


-bb

[HandymanHerb]

so I should be fine with this then right?
http://shop.genuinedealz.com/Items/Item ... 0BLK%20/ft


-bb

YEP

[MH Hawker]

I may be wrong in my thinking, but the older 55 pound thrust motors did draw around 50 amps at 12 volts and the new 110 pound thrust motors still draw 50 amps but at 24 volts so 8 gage will cover about any of them.

[blackberg]

Thanks for the help so far.
I dont want any significant voltage loss, if I could avoid it.

Thinking about it more, I think the actual run will be about 16-18 feet.

And I think having it opposite of the console, the same side the gas is is the best place for weight distribution.
I will have each one in its separate box away from each other.

-bb

[blackberg]

Thanks again for the help,

ordered 20ft of 6-gauge this morning, didnt want to be short

also ordered one of these for the plug
http://www.amazon.com/gp/product/B002UC ... =soca0f-20

already had a circuit breaker.


thanks

-bb

[rancherlee]

I may be wrong in my thinking, but the older 55 pound thrust motors did draw around 50 amps at 12 volts and the new 110 pound thrust motors still draw 50 amps but at 24 volts so 8 gage will cover about any of them.

You thinker has thunk correctly, double the voltage = half the amperage. I run a 40amp circuit breaker on my 55lb and have never tripped it, 8 gauge is plenty. Also remember if you are installing a separate battery in a different location on the boat make SURE to fuse/breaker both ends of the cable linking the remote battery(s) to the main since power can flow both ways.

[blackberg]

I went with the 6 over the 8 since it was only $9 more, and will reduce the voltage loss by about 50% since it is a long run,
its not much averaging about 1%-2% during normal usage, but when the batteries start to run out, it can be 4-5% of remaining battery life making it that much lower.

-bb