When I bought the house it had a section of triplex wire that ran to a 50A breaker with the remainder coiled in rafter space of the covered porch. (When I discovered this, the triplex was hot. That breaker is currently off and taped off.) I would like to put a sub panel in the garage, which shares the covered porch.

Can I use the existing triplex for this?

Edit: Present wire consists of 1 aluminum uninsulated, and 2 insulated wires. The insulated ones are marked CANADA I Wire 4 Aluminum 6 and some illegible stuff in orange. I need to uncoil it to find a better copy.

My suspicion is "no"

Thinking about this, it's definitely a 'no' The whole point is to get 220 for a new table saw. Which means 4 conductor wire, not 3.

Failing that, what is the best way to use the existing triplex wire to get acceptable code wire from the rafter space to the main panel without taking apart the wall?

  • Cut the triplex off short of it's entry point into the house wall.
  • Tape/solder conventional wire to the triplex.
  • Shut off the power, disconnect the triplex from the breaker, undo the strain relieve, and try to worry it all back into the main panel box..


Do the same operation but do the feed from the main panel end.


Use the triplex to get someing more flexible through the route (fish tape? Rope?) and attach the new wire to it?

  • 3
    Does he triplex have a white neutral or a bare ground? – Harper - Reinstate Monica Jun 3 '19 at 18:04
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    Depends on wire size and other factors. Is there any label printed on the cable sheath? – manassehkatz-Moving 2 Codidact Jun 3 '19 at 18:20
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    Also is this wire #4 or above? How do you feel about having 120V-only in the garage subpanel? – Harper - Reinstate Monica Jun 3 '19 at 18:49
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    Can you post the labeling information written on the cable sheath? Also, does the triplex consist of three insulated wires, or two insulated wires and a bare wire? – ThreePhaseEel Jun 4 '19 at 0:03
  • Edited to include part of wire label. – Sherwood Botsford Jun 4 '19 at 20:42

Triplex is designed and approved to be suspended on free air across open space. You need an altogether different type of wire.

  • There are several styles of "triplex" -- overhead distribution, URD, and "mobile home feeder" (which is really a quadplex cable) – ThreePhaseEel Jun 4 '19 at 0:02

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