question

rporcoro avatar image
rporcoro asked

Multiplus 12|3000|120 AC-Out-1 wire size

I just want to be sure that I am getting this right. When running the AC in or out wires my inverter will be 32 feet from the breaker panel/box. Will 6/3 wire be enough for that length?

Multiplus-II
2 |3000

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2 Answers
Justin Cook avatar image
Justin Cook answered ·

Hi @rporcoro, yes, 6/3 will be more than sufficient for that - 6AWG can carry 120A continuous safely, and at 120VAC you'll only experience roughly a 0.53% voltage drop over the course of that run.

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Kevin Windrem avatar image
Kevin Windrem answered ·

The wire type significantly affects ampacity. The chart I found specs #6 for 55 amps at 60 degrees C (e.g., NM-B (romex)) and 65 amps at 75 C (THWN or SO), and one for "marine" wire is rated for 120 amps at 105 C outside engine space or 102 amps inside the engine space.

The AC in on a Multi 3000/120 is rated for 50 amps, but the AC out can benefit from power assist for an additional 3000 VA (25 amps). So the total for both AC 1 and 2 out could be up to 75 amps with full shore power and power assist. You'd want to limit the output current with a circuit breaker for the wire type you end up using. (AC 2 out is limited to 25 amps.)

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Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.