wiring

[Mark Spencer2]

Up-graded to a 24 volt trolling motor on my pt 175, should I up-grade the wiring from the batteries, it

 

[David Lewis]

Hey mark, not sure what size wire is in the 175. A rule of thumb. 12 guage is good for 20 amps, some say 30 but why push it. Even though the 24 volt will only require 1/2 the amps to do the same amout of work as the 12 volt. (if 12 volt draws 20 amps the 24 would draw 10 amps -like the old 12-24 volt motors) You would need to read the tag on the trolling motor and look for Max Amp. draw, you could then know if the wire is large enough. Mine is a 67Lb. thrust and has 6 guage run to it.

12 ga. - 20 amps

10 ga. - 30 amps

8 ga. - 40 amps

6 ga. - 60 amps

These are conservative figures, but better safe than sorry.

 

[Dennis Mathis]

I would tend toward a larger wire size. The DL suggested gauge sizes are reccommended by the National Electric Code, but are sized to prevent excessive heating in the wires. For low voltage systems, voltage drop (and power loss) is a bigger concern. For example 20 amps in a 12ga wire 40ft long (20 ft x2 from positive and back to negative) will result in 1.2 volt drop. For many systems with a 12/24 switch the voltage drop doubles. I would recommend 6 or 8 gauge. 30 amps in a 6ga wire has a 0.5 volt drop or 2% power loss in direct wired 24V trolling motors .