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Can I run 2000W of metal halide from one typical house outlet?

Posted by canuckistani 5b (My Page) on
Tue, Mar 24, 09 at 15:25

I have two 1000w Metal Halides wired to the same timer that has one outlet plug. Can I run these two metal halides off of one typical home outlet socket?

What is the effective limit per socket or outlet?


Follow-Up Postings:

RE: Can I run 2000W of metal halide from one typical house outlet

I wouldn't try.

Household sockets are either rated for 15A or 20A (the latter mostly in kitchens and garages; the former, most everywhere else). 120V (which you're lucky if you actually get that much out of the socket) * 15A is 1.8kW. 120V * 20A is 2.4kW, but you'd be lucky if you could actually draw that much; fuses and breakers in the US are designed to throw early, not late. It's not recommended that you draw more than 13A for extended periods.

Plus, we're not accounting for ballast losses here -- only bulb draw. I assume that bulb draw is separate from ballast draw in that 1000W rating. You could use a Kill-A-Watt meter to find out for sure just how much they're using; they're cheap and very handy to have around.

If you're good at wiring, *and* your sockets are on the same phase, *and* your timer is rated for that much current (notice all of the conditionals here), you *could* wire two plugs together onto the same cord. If your sockets are opposite phase, though, that won't work.

In short, I wouldn't put more than 1.5kW on a socket if I were in your shoes. Just get another timer. Besides, that gives you redundancy: one timer goes, you don't lose both lights.

RE: Can I run 2000W of metal halide from one typical house outlet

  • Posted by rokal LongIsland/z6b (My Page) on
    Tue, Mar 24, 09 at 18:03

Are you running 120 volts? If so, then this is not a good idea!

The load on a circuit should not exceed 80% of its rated capacity.

A 15 amp circuit can carry only a total of 1440 watts,which is 80% of the 1800 watts found by multiplying the volts times amps,15 x 120 x 80%= 1440.

A 20 amp circuit can be loaded 1920 watts, 120 x 20 x 80%=1920 watts.

Additionally, depending on the technology, each 1000 watt fixture will draw more than 1000 watts of power.


RE: Can I run 2000W of metal halide from one typical house outlet

Thanks for the info guys. So if I understand correctly, connecting one 1000W metal halide to individual sockets on the same outlet should work just fine?

RE: Can I run 2000W of metal halide from one typical house outlet

Yes. Each individual socket is nominally rated for 15A (from which you shouldn't plan on drawing more than 13A). Now, there are limits on how much current can be drawn over an entire circuit, but it's unlikely you'll hit them with just two HIDs.

RE: Can I run 2000W of metal halide from one typical house outlet

Depending on how far away and how easy it is to get to, I would consider adding a 30 amp breaker and running wire to an outlet in the room.


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