[barefoot]

Hello,
I'm in the process of replacing the steaming and anchor lights on the mast while it's down and could use a little guidance.
Is 14 gauge overkill or will 16 due and is duplex the right wire or do I need triplex?
Also I read some time ago a member suggested insulating the wire with pipe insulators to protect from chafe..any thoughts?

 

[Bene505]

I believe LEDs could use 20 or 22 gauge wire. But you'll need a fuse or circuit breaker that limits the current to a level that the wire can handle (need it on any guage actually).

Regards,
Brad

 

[barefoot]

Thx for quick response Brad!!

 

[muttskie]

While using LEDs for navigation lights will reduce needed amperage to the fixture, the thing to remember is the length of the run and the needed voltage at the fixture. So, the gauge of the wire needed is determined by both values.
A long run (keep in mind it's the length to and from the fixture) means a greater voltage drop, necessitating a wire of adequate size to keep the voltage in the correct range for the fixture.
When I installed my LED tricolor on the top of a 30 ft. mast, the manufacturer of the light recommended AWG14 wire based on the distance from the circuit breaker switch to the light and back.
The general assumption that you can use very small wires for LEDs is not really correct. You have to do the voltage drop/distance calculation.
Hope this helps.

 

[mitiempo]

I wouldn't use wire smaller than 14 gauge for mast wiring whether Led or not. Maybe even larger (12 gauge) depending on length of run. Voltage drop is one issue and the durability of the wire is another. ABYC calls for wire to be no smaller than 16 gauge - smallest I use for anything is 14 gauge. Also there may not be an Led there in the future for some reason - the larger wire works whether incandescent or Led.

 

[barefoot]

Thank you all! After further investigation,voltage drop seems to be the concern…So 14 it is.
Thanks again for your help!!

 

[Bene505]

Doing some quick searches, this example LED masthead light uses 200ma at 12v.

My favorite voltage drop calculatior is Voltage Drop Calculator Genuinedealz.com

Using 140' round trip gives a voltage drop of less than 5%.

Perhaps use a bigger wire for other reasons, but you don't need it for voltage-drop reasons. I'd probably take the above advice and go with 16 gauge, for reasons of chafe and also because my circuit breakers are alreay in place to protect that guage wire. If you are using 3 wires, the allowable amperage outside of engine spaces is 17.5 amps (from that same voltage-drop-calculator page). So a 15 amp breaker would be needed, unless I'm mistaken. That might be the breaker size already in place for your incandescent mast lights -- worth checking as part of the possible decision to go to 14 gauge.

Regards,
Brad