Proper gauge wiring for inside courtesy lights

[Brassmonkeys]

I purchased these lights from amazon that work fantastic when I touched them to a 9v battery however I was wondering what gauge wire you would use to connect multiple lights (probably 6) on the same line. Should I just use 22awg for the entire run?

See picture of light details

[Wotname]

Electrically speaking, 22AWG is suitable.

Mechanically speaking, you might find a larger gauge is more suitable (20 or 18) but this depends of the location, cable securing, termination types, insulation etc.

[Spot]

Brassmonkey,
We'd need the real specifications of the LED's (volts and amps per unit) and the round trip run of the wire to do a proper calculation.

Even though the pigtail is 22 AWG, the main trunk wire might need to be heavier as there will be 6x of something running through it if you wire 6 units on the same run.

Then there are recommendations for max voltage drop and minimum wire size by organizations like ABYC and USCG (in the USA).

If you know amps and round trip length you can look it up on a chart too.

I do agree that 'bigger' wires feel a bit better for routing and crimping.

[Wotname]

We can make an educated guess at the power requirements of the proposed LEDS. From the OP's attachment, the lights are using three 2835 SMD LED each.

The 2835 LED uses about 0.06W at ~3V. Assuming a simple internal dropping resistor for 12V operation, the light will be using ~0.72W. Thus 6 lights will be using ~4.3W which at 12V, is ~360 mA.

Voltage drop will not an issue for LEDs on a sailboat and the OP notes they are 'fantastic' even at 9V.

Thus 22 AWG will be electrically suitable.

[Lake-Effect]

ABYC asks for a minimum of AWG#16, but that's mainly for the strength of the wire. They have recently looked with favour on smaller gauge wire as long as it's physically robust - eg a pair of AWG#22 wires with an overall jacket.

[Bill Seal]

As an example, ordinary household type extension cords (zip cord) are 18 awg, I would think anything smaller would not be physically strong enough for boat wiring.

[Spot]

Wotty, thanks for the math. They make those 2835 LED chips in various power ratings. Seems like .06w and .2w are easy to see online. That is a 3x difference right there.

If the OP can find out the power consumption of one unit at 12.7v, the numbers could be added up and fed into the calculator below and the effects of wire length and voltage drop could be seen:

https://www.rapidtables.com/calc/wir...alculator.html

[Wotname]

I do think we get hung up at times on physical strength and wire sizes for the mythical "marine" use.

Aviation (including helicopters) regularly use 20, 22 and 24 AWG wiring - miles of it!
Yes, the insulation is tougher but so are vibration levels.

I concede installation practices and general workmanship do vary however the point is skinny wire can be robustly mounted etc etc.

[Lake-Effect]

Originally Posted by Wotname

I do think we get hung up at times on physical strength and wire sizes for the mythical "marine" use.

Aviation (including helicopters) regularly use 20, 22 and 24 AWG wiring - miles of it!
Yes, the insulation is tougher but so are vibration levels.

I concede installation practices and general workmanship do vary however the point is skinny wire can be robustly mounted etc etc.

Agreed. It's not overspeccing the gauge because "marine", it's more the way marine wire is often pulled and run (by trained gorillas ). What little aviation wiring I've seen is well-bundled and protected.... certainly moreso than most boat wiring.

[GordMay]

As noted, the smallest wire gauge size allowed by ABYC E-11, AC & DC Electrical Systems on Boats, is 16 AWG, [with some exceptions for 18 AWG], and using the app is more precise, than using the ABYC tables.

ABYC Wire Sizer App [$4.99] ➥ https://abycinc.org/page/wiresizer
And ➥ https://abycinc.org/news/370589/ABYC...Sizer-App-.htm

[smac999]

Originally Posted by Brassmonkeys

I purchased these lights from amazon that work fantastic when I touched them to a 9v battery however I was wondering what gauge wire you would use to connect multiple lights (probably 6) on the same line. Should I just use 22awg for the entire run?

See picture of light details

The smallest power wire allowed in a boat under abyc is 16awg...

[Nicholson58]

Follow the rules, 16 ga. I rewired our forward cabin with light gage for LEDs. Had to do it all again after the lightening hit. Nothing left of the small stuff but smoke trails and fused multi strand. Heavy wire survived.