Size of trolling motor wiring
14ledo81
Posted 11/11/2014 11:14 AM (#739577)
Subject: Size of trolling motor wiring





Posts: 4269


Location: Ashland WI		When I moved my battery for my electric trolling motor (48lb thrust), I noticed a loss of power.

Not knowing, I had installed about 7' of 14 gauge wiring connecting it. Would this cause loss of power?

I had thought undersized wiring would cause overheating problems (and potential safety issues), was not sure it would cause loss of power though.
tcbetka
Posted 11/11/2014 11:40 AM (#739585 - in reply to #739577)
Subject: Re: Size of trolling motor wiring




Location: Green Bay, WI		Absolutely...wire size (diameter) has a direct influence on its resistance:

http://www.powerstream.com/Wire_Size.htm
mnmusky
Posted 11/11/2014 11:44 AM (#739586 - in reply to #739577)
Subject: Re: Size of trolling motor wiring




Is the wire getting warm/hot when you run the motor for a bit? If yes, you probably have too small gauge wiring and high resistance.
Trophyseeker50
Posted 11/11/2014 12:26 PM (#739592 - in reply to #739577)
Subject: Re: Size of trolling motor wiring





Posts: 791


Location: WI		As a certified electrician reading this I have to tell you I literally gasped when I read this! I don't mean to offend but 14 gauge wire is good for less than 20 amps. Your trolling motor more than likely recommends a 40 amp fuse. Proper size wire would be a min of a #8 gauge. #6 preferably. You are putting your self at risk for a serious disaster. I am not being dramatic. This is how fires start. Also make sure that you are using a tinned marine grade wire. Again I mean no disrespect but this is serious.
kjgmh
Posted 11/11/2014 12:36 PM (#739595 - in reply to #739577)
Subject: Re: Size of trolling motor wiring





Posts: 1095


Location: Hayward, WI		Direct from Minnkota: http://www.minnkotamotors.com/WorkArea/DownloadAsset.aspx?id=1429
Trophyseeker50
Posted 11/11/2014 12:57 PM (#739599 - in reply to #739577)
Subject: Re: Size of trolling motor wiring





Posts: 791


Location: WI		Good link^. Remember that marine grade wiring has different amp ratings than your standard wire. This is why I said that 14awg is rated under 20 amps rather than 15 in say a Romex or thhn wire.
14ledo81
Posted 11/11/2014 2:50 PM (#739625 - in reply to #739592)
Subject: Re: Size of trolling motor wiring





Posts: 4269


Location: Ashland WI
Trophyseeker50 - 11/11/2014 12:26 PM

As a certified electrician reading this I have to tell you I literally gasped when I read this! I don't mean to offend but 14 gauge wire is good for less than 20 amps. Your trolling motor more than likely recommends a 40 amp fuse. Proper size wire would be a min of a #8 gauge. #6 preferably. You are putting your self at risk for a serious disaster. I am not being dramatic. This is how fires start. Also make sure that you are using a tinned marine grade wire. Again I mean no disrespect but this is serious.


Good to hear. I needed something like this.

I guess I used it because the wire coming off of the pedal did not seem very big. I was visually trying to match sizes.

I can't say it ever gets really hot, but then I am not on it very often. My boat is small and light, and it does not take much to move it.

BTW, I appreciate your honesty. I am a licensed journeyman plumber so I understand what can happen when "rookies" (myself here) try to do things.