wire size for electric trolling motor

[38plymouth]

I have an electric trolling motor that I mounted to the front of a 20 foot pontoon boat. I ran pretty heavy wire from the motor to the battery that is mounted in the rear. I don't remember the gauge of the wire I used (8 gauge is sticking in my head). The motor doesn't seem like it has the power it did when it was mounted on my last (smaller) boat. I'm wondering if the wire is too small and that it could be causing the problem. The wire is probably 22-23 feet long, is there a way to tell what gauge it should be?

 

[Ralph 123]

Re: wire size for electric trolling motor

Yes just visit this link and it will tell you the proper gauge.<br /><br /> http://www.ancorproducts.com/Technical_information/Wire_calculator.htm

 

[kball]

Re: wire size for electric trolling motor

Not to piggyback onto someone else, but this is a very similar question to what I'm wondering.<br /><br />I just bought a motorguide PRO70 70# motor. THe manual suggests 6 gauge wire. I only plan to run about 6' of wire from the battery to the plug. According to the calculator in the link, 10 gauge is all that is required. Who should I believe?<br /><br />M

 

[Ralph 123]

Re: wire size for electric trolling motor

The Manual. Did you put in 6ft or 12ft? It should be 12.<br /><br />IMPORTANT!<br />Length (feet): Determined by measuring the length of the conductor from the positive (+) power source connection to the electrical device and back to the negative (-) power source connection. Note that the power source connection may be either the battery, panelboard or switchboard. Current (amps): Determined by adding the total amps on a circuit. Conductor sizes not covered in Table B or Table C may be calculated by using the following formula: CM = K x I x LE<br /><br /> http://www.ancorproducts.com/Technical_information/Conductor_Sizes_B.html

 

[38plymouth]

Re: wire size for electric trolling motor

I can't get the first link to open. If I play it safe and say I have 50 feet of wire, what size wire do I need?

 

[kball]

Re: wire size for electric trolling motor

what is your amp draw and voltage?

 

[Realgun]

Re: wire size for electric trolling motor

If the wire is 14 FT total to and from length and you draw 50 amps @ 24V then 10 is all you need However the MFG does not know the true lenght and really is just protecting the customer. Also there is a surge current with motors. What if the surge is 100 Amps? Then guess what your at 6 guage.

 

[kball]

Re: wire size for electric trolling motor

But wouldn't the 50A breaker that the manufacturer recomends prevent that from being an issue? I figured that Motorguide was just defaulting to the 6 awg because, as you said, they have no idea of the length. I'm probably going with the 6 awg, but was just wondering why they wanted that much wire when it seems like overkill. Thanks for your help.<br />M

 

[Homerr]

Re: wire size for electric trolling motor

Like house wiring... When in doubt... Use the next largest size. <br /><br />Only thing that will hurt is your pocketbook!<br /><br />I just got my Minn-Kota 55PD, and it says to use 8 ga. wire.<br /><br />H.

 

[Silvertip]

Re: wire size for electric trolling motor

Mac -- Surge current is an issue with fuses as they tend to open immediately at their rated current. Circuit breakers are a little more forgiving and can tolerate a little surge current.