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Electrical Wiring

14 ga romex for low voltage wiring?

8 years ago

I am planning to install an Armacost undercabinet lighting kit, sold by Home Depot. It's a 12' run of LED tape lighting, running about 20 watts of 12 volt DC power (I already purchased the compatible 30w power supply). It'll have to be split into four different strips due to my cabinet configuration, and I'm wondering which type of wire I should use for the in-wall/attic runs. On the installation manual it recommends 18 AWG, but I'm not familiar with that. What I read keeps saying it's thermostat cable?

Would a 14 ga romex be superior to this for in-wall use? I am concerned about voltage drop, FWIW.

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Comments (5)

kudzu9
8 years ago
Well, 14 gauge Romex would be good if you were running, say, a 1500 watt load at 120 volts AC, but it is way overkill for your application. 18 AWG is used for connecting up home thermostats...and for a lot of other low wattage DC applications. It won't hurt anything to use larger diameter wire, but why do you think the manufacturer is recommending 18 AWG if it wouldn't be adequate?
User
8 years ago
It depends on how many amps per run, and how long the wires are.

.

If you are splitting up the 12' of lighting like this (array), 18 is probably fine.

The wire has to be rated for in-wall use.
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kudzu9
8 years ago
last modified: 8 years ago
bobstrauss-

Let's be clear: you are talking about one strip of LEDs that draw 20 watts total...correct? You aren't talking about buying 4 of those strips and hooking them all up, or are you? And if you are splitting up one length of these lights, how are you going to connect them all together? I still think you'd have plenty of leeway, but I just want to have a little more clarity on what the physical configuration is supposed to be.
bobstrauss
Original Author
8 years ago
It'll be 12' total, divided into 4 strips. In all, this should draw 20 watts of power.

I planned to run two 18 or 16 AWG legs off the dimmer:

Leg one: first a 2' run of LED tape, then connected by 18 or 16 AWG cable (run through the wall) to a 4' run of LED tape.

Leg two: first a 4' run of LED tape, then connected by 18 or 16 AWG cable (run through the wall) to a 2' run of LED tape.

Aside from the connection at the dimmer, there will be no splices at all in the wall - they will all be spliced under the cabinet using Armacost brand connectors.

That was the plan, at least.
dennisgli
8 years ago
Armacost sells wire - why not just use that?
2C White LED 18AWG In-Wall Power Wire

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