Battery cables for tm

[progator123]

I,ve been having problems with my 30amp breaker tripping on my 24 volt tm. Cleaned all connectors and replaced breaker. This only happens when i have to run on max spd. Should i replace cables and what gauge wire should i use.

[Grey Wolf]

Six gauge.

[K_Mac]

You are probably pulling more than 30A at full speed. My MK recommends a 60A breaker and #6 wire. Full load is 54A according to the manual.

[progator123]

Thanks for the info.  I will try going to a 60 amp breaker.

[K_Mac]

Thanks for the info. I will try going to a 60 amp breaker.

Just make sure your wiring is rated for 60A. #8 for a shorter run might be OK, but #6 if going from the back to the bow would be better. I'm no expert, but went through all this a couple of years ago while refurbishing my boat. Good luck.

[slonezp]

Thanks for the info. I will try going to a 60 amp breaker.

Make sure the motor is rated for a max of 60 amps. if 30 amp is the max and you put in a 60 you'll burn up the motor.

[K_Mac]

Thanks for the info. I will try going to a 60 amp breaker.

Make sure the motor is rated for a max of 60 amps. if 30 amp is the max and you put in a 60 you'll burn up the motor.

That is an excellent point. I just took for granted the motor rating. That is not good idea.  :-[

[Team_Dougherty]

Make sure the motor is rated for a max of 60 amps. if 30 amp is the max and you put in a 60 you'll burn up the motor.

The breaker is to protect the wiring, to keep your boat from catching fire, not the motor. Use a 60 amp breaker if you are using 8 awg wire.

The motor will draw what ever current it needs to run. If the motor draws 50 amps on high it will blow your 30 amp breaker all the time.

[progator123]

Thanks for info. 

[slonezp]

Make sure the motor is rated for a max of 60 amps. if 30 amp is the max and you put in a 60 you'll burn up the motor.

The breaker is to protect the wiring, to keep your boat from catching fire, not the motor. Use a 60 amp breaker if you are using 8 awg wire.

The motor will draw what ever current it needs to run. If the motor draws 50 amps on high it will blow your 30 amp breaker all the time.

Yes and no.

You are assuming the motor is in perfect working order. If the motor has been working ok, not tripping the 30 amp breaker up until now, I would believe there may be something causing additional resistance and tripping the breaker. Could be an internal issue which may be repairable before smoking the motor. Could be fishing line. If the motor RLA is 30 amps and it is drawing 50 there is something wrong. If you just change the breaker to a 60 you may smoke the motor and it will no longer be repairable. We don't know if this motor is equipped with an internal overload for motor protection, and even if it is, that doesn't mean it works properly.

I guess the question to ask is...

Is this a new problem, new boat, or was it working ok up until now and just recently started happening?

[Way2slow]

I see all these recommendations and not once has anyone asked what size TM.  Knowing the size/amp draw and how long the cables are from the battery to the TM and if it's a four wire 12/24 system in the boat or just the two wire system.  These are all things needed to determine the size cable or circuit breaker needed. 

With todays big 80+ thrust TM's, 6 guage wire is not always big enough.  In a four wire 12/24 installation it's surely not large enough if you do much running on high.   In most cases, 4 guage is needed.  I'm pulling out my 6 guage and installing 2 guage for my new 80#, 24V TM.   Since mine is only a two wire system, 4 guage would be big enough but I already have the 2 guage wire so I'm going to it.  You figure that motor can draw close to 60 amps on max, for a 40' length (you have to figure the total length of all cables) that's actually too much for 6 guage without creating a voltage drop.

6 guage is not going to over heat, but you will get internal resistance that's going to cause some voltage drop.  Any voltage drop is a loss of efficiency and power.   

Also, don't forget the connector, those three and four prong AC style plugs are not going to cut it.

[Fishing Rhino]

A fuse/circuit breaker is to protect everything, not just the wiring.

My Humminbird sounder says to use a three amp fuse in the circuit.  Using anything more will void the warranty.

You can develop a short in any trolling motor which can indeed burn out the unit if you exceed the maximum amperage they recommend using in the circuit.

You want the breaker to trip before you can damage the unit, or ignite any flammable materials along the way.