Low voltage indoor light install - wire gauge?

Old 07-23-17, 04:42 PM
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Low voltage indoor light install - wire gauge?

I am looking to install 3 35w low voltage (12v) spots in one a room mounted to exposed beams. The lights I want are mean to be plugged in and come with a small transformer at the plug end. I plan to repurpose these by replacing the wire that came with it and run a new cable between 3 fixtures to a new transformer that will handle the wattage. Because they will be mounted in beams the cable will be visible and I'd like to get the smallest cable possible. From the furthest light to the transformer will be about 30 feet. The lights are halogen.

Can someone please help me figure out what is the proper gauge cable to use. 16 or 18 gauge would be ideal to not be noticed but I am not sure if that causes too much voltage drop.

Any suggestions and guidance?
Old 07-23-17, 07:59 PM
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Just responding to the wiring part of your job. You're talking about a 10A load.
I'd try to run at least #16 to keep the voltage drop minimal.
Old 07-23-17, 08:02 PM
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I came up with 10 gauge wire to stay within recommended voltage drop (4%) given the 12 volt supply.

Smaller wire and not only will you lose energy efficiency due to less brightness versus power consumed but also the three lights may be noticeably different from each other in brightness.

I would run bare single conductor wire on opposite sides of the beam (2 conductors) compared with one Romex cable with ground. This would make the wiring less conspicuous.

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