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Replace NEMA L5-30P Plug With NEMA 5-20R?

I didn't read the specs carefully enough when I ordered the APC SUM3000RMXL2U UPS. It came with a NEMA L5-30P plug, but I only have a NEMA 5-20R receptacle available. Can I just replace the plug? (I realize the UPS capacity will be 2000 VA instead of 3000VA.) Or must I get a 30A circuit installed?

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8/22/2022 - Mon

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Well, it's not the UPS that draws the power but the attached devices, so if I keep the load within the 20A limit it _ought_ to work. See the attached article in the APC Knowledge Base that discusses using less than fully rated plugs and circuits with UPSes of this general type, although it does not actually show the specific case of putting a 30A UPS on a 20A circuit. But in the end I sprung for an electrician to pull in a 30A circuit.

Thanks for your answer.

I've been in industrial electronics since 1981.
I know how loads work, thanks.

What you suggest would work as long as you never EVER 'forgot' and attached too much load. If you did you might cause a fire or injure someone.

You would also be ignoring the electrical codes when you rewired it that way and if that fire happened or someone got hurt you'd be liable for the damage/injury.

So, I'm glad you took my advice.

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