Wire size?

[Folie]

I have my mast down for varnishing and now is the time for new wires too.

Please help me with wire size and advise duplex -- yes/no.

1 Anchor light, LED, wire length is 45 ft.

2 Spreader lights, LED wire length is 25 ft long

3 Mast light (please-- what is this white forward facing light called!?) wire length is 15 ft. Incandescent bulb

Thanks a lot--- Rick

[Cruisingscotts]

You need to size the wire based on the round trip. Determine how many watts or amps your light draws at the given voltage and look at a wire chart for approprite sizing and lengths. Example, anchor light wire dist = switch/breaker fuse to light back to neg buss terminal or battery negpost. If you look at Anchor or Cobra wire online they sell a purpose made multiconductor for mast lighting applications, just make sure the size works for your fixtures. Bluesea, Anchor, cobra and lots of other places have wire sizing charts online. The fwd facing white is most likely a steaming light, to be on when motoring at night. Highly advise removing the incondesant and replacing with a LED.

[Cheechako]

Duplex is nice in the mast, but the cost differential is huge last I checked. Also, you can get more colors in single wire.... and once bundled probably doesn't matter.

[babaluey]

If you have an iphone/ipad get this app: DC Wire Sizer - it may also be available for android; if not I'm sure there are similar ones.

[Folie]

Thanks to everyone-- and yes, I agree---- LED's are great.

[Cruisingscotts]

Here you go, right down the road..

Ancor Round Mast Cable | Redden Marine Supply

Guessing you have a box section section mast, this is what I would use. Run a seperate 2 cond for the spreader lights, go bigger on the spreader lights in the event you ever need to use halogen or some other higher amperage. On each one pull in a chase line and secure it to the wire just inside the water tight termination.

[pcmm]

Build your own cable if you can. You want 1 heavy ground lead that you can split off at the steaming light/deck light and then continue to the masthead. If you use duplex cable, you'll end up with several ground leads and much more bulk (which can be a problem if you're running in a conduit. its also much less expensive if you build it that way.

[skipmac]

Here's a handy, online wire size calculator. Input the one way distance from power to load (calculator then figures size based on round trip), amp load and a wire size and it gives you the voltage drop. If you think that drop is too much try a larger wire.

1. For your LED anchor light 18-20 gauge looks good.

2. For the spreader lights, 20-22 gauge.

3. The steaming light (that's the light you have to use when under power) would draw more power but shorter run so 18-20 as well.

[Folie]

Originally Posted by Cruisingscotts

Here you go, right down the road..

Ancor Round Mast Cable | Redden Marine Supply

Guessing you have a box section section mast, this is what I would use. Run a seperate 2 cond for the spreader lights, go bigger on the spreader lights in the event you ever need to use halogen or some other higher amperage. On each one pull in a chase line and secure it to the wire just inside the water tight termination.

Yes-- Folie's mast is a 'box'. Thx for your reply

[Folie]

Originally Posted by skipmac

Here's a handy, online wire size calculator. Input the one way distance from power to load (calculator then figures size based on round trip), amp load and a wire size and it gives you the voltage drop. If you think that drop is too much try a larger wire.

1. For your LED anchor light 18-20 gauge looks good.

2. For the spreader lights, 20-22 gauge.

3. The steaming light (that's the light you have to use when under power) would draw more power but shorter run so 18-20 as well.

Thx for the help. You mentioned an online wire calculator that you like--- Please- what is its link?

[Folie]

Originally Posted by pcmm

Build your own cable if you can. You want 1 heavy ground lead that you can split off at the steaming light/deck light and then continue to the masthead. If you use duplex cable, you'll end up with several ground leads and much more bulk (which can be a problem if you're running in a conduit. its also much less expensive if you build it that way.

Pcmm--- interesting idea. Thank you.


So to clarify--- this heavier ground wire goes the length of the mast and is "cut" and "junctioned" with connectors at the SteamingLite and at rhe SpreaderLites. Since the mast is down I can do a good job and solder these connections- but still- wouldn't homeruns be better? OOOOOHHHHH-- wait---- these LEDs are picky I think-- if you don't get the wires right they flat out don't work, I THINK. With home runs, you can just switch the wires, but with one groundwire-- I think you may be in trouble. WhatDoYouThink?

[cal40john]

Originally Posted by skipmac

Here's a handy, online wire size calculator. Input the one way distance from power to load (calculator then figures size based on round trip), amp load and a wire size and it gives you the voltage drop. If you think that drop is too much try a larger wire.

1. For your LED anchor light 18-20 gauge looks good.

2. For the spreader lights, 20-22 gauge.

3. The steaming light (that's the light you have to use when under power) would draw more power but shorter run so 18-20 as well.

ABYC recommends no smaller than 18 G in a multi wire sheath, otherwise 16 G minimum gauge. I believe I've read that's due to physical, not electrical issues.

American Boat & Yacht Council Standards for Boats E-11 | Ancor

[skipmac]

Originally Posted by Folie

Pcmm--- interesting idea. Thank you.


So to clarify--- this heavier ground wire goes the length of the mast and is "cut" and "junctioned" with connectors at the SteamingLite and at rhe SpreaderLites. Since the mast is down I can do a good job and solder these connections- but still- wouldn't homeruns be better? OOOOOHHHHH-- wait---- these LEDs are picky I think-- if you don't get the wires right they flat out don't work, I THINK. With home runs, you can just switch the wires, but with one groundwire-- I think you may be in trouble. WhatDoYouThink?

Oh noooo!!

You mentioned solder and will now start the endless solder vs crimp debate (right up there with guns, anchors and cats vs mono in controversy). Either way, you are cutting into the ground wire half way up and introducing a weak spot and a place for corrosion to potentially start in (good, adhesive fill crimps or shrink tubing will help that). For several reasons I would just run + and - to each light.

One trick using separate ground wires will enable. If you want to add a tricolor nav light at the top of the mast along with the anchor light you can do that with just one pair of wires instead of separate wires to each light.

Connect the wires from both lights to the two wires from the switch below but reverse the wires going to the lights. So light 1 is + -, light 2 is - +. No power to the wires of course both lights off. Power + - turns on one LED but the other is off since LEDs only transmit current in one direction. Reverse the power, - + and the other LED lights, the first one goes off.

[skipmac]

Originally Posted by cal40john

ABYC recommends no smaller than 18 G in a multi wire sheath, otherwise 16 G minimum gauge. I believe I've read that's due to physical, not electrical issues.

American Boat & Yacht Council Standards for Boats E-11 | Ancor

Good point about ABYC. What about duplex wire? Would that permit smaller gauge under ABYC?

[btrayfors]

AWG16/2 duplex marine tinned cable for the LED nav lights.

AWG14/2 duplex marine tinned cablefor the spreader lights (for reasons listed above).

This stuff is not expensive.

Good source: Marine Wiring, Boat Cable and Electrical Genuinedealz.com

Bill