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whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9
reply to sk1939

Re: Any reason I would need to step up to 30A circuit

said by sk1939:

Safe as long as you don't fully load both, otherwise you need two circuits.

Not safe at all. If they are cord & plug devices, they need two separate circuits, plain and simple. To begin with, UPS as well as the equipment they normally power are continuous loads. The circuit breaker requirement if both were to be on the same circuit is:

(2200 + 1400)kVA / 120V * 125% = 37.5A

meaning that a 40A circuit breaker (and branch circuit) is the minimum required size. Together, the UPSs can easily draw close 40A during battery charging after an outage.

Frankly, the 2200kVA UPS exceeds the allowable requirement to be on a 20A circuit alone. You can get away with one separate dedicated 20A circuit for the 2200kVA rated UPS if your kW load of the UPS is no more than about 1730 kW and has power-factor corrected power supplies, meaning the load is no more than 1730kVA as well. This provides only a 10% overhead for the internal UPS controls and battery charging lasts no more than 3 hours. Putting both on the same 20A circuit? No. You will most certainly overload the circuit; especially after an electrical power failure when the UPS need additional current to charge batteries. And it would be pretty stupid to put everything on UPS, and then have the breaker trip after a power failure.

sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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·Verizon FiOS
Safe in the sense that if you only load them to 40% (good practice for run-time). Otherwise yes, the draw is more than the circuit can provide. Ideally you should have a circuit for every UPS over 1500VA, but I've seen multiple UPS's on a single circuit.


joako
Premium
join:2000-09-07
/dev/null
kudos:6
reply to whizkid3
Picked up and installed the 2nd unit today, final configuration is 2x 1400's with 5-15P plugs on the same 20A circuit. Should have taken a picture of the label but basically it gives the max load depending on what plug is fitted. I have a 2200XL at another site with a 20A plug.

APC says you can even put a 15A plug on a 2200: »sturgeon.apcc.com/Kbasewb2.nsf/F···Document



--
PRescott7-2097


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9
said by joako:

APC says you can even put a 15A plug on a 2200

You left a few bits out. APC says this only about the exact model SU2200NET and then only if you limit the load to 1200VA. All of the other APC units must have a 20A plug. And all of these, the 2200NET included, must be on a dedicated circuit. Note that the 2200NET ships with a 20A plug because a dedicated 20A circuit for this UPS alone is what is required in most applications.

Like I said before, it is pretty foolish to spend money like this for UPS equipment, and then have the circuit breaker trip and dump your IT load.

What are the model #s you are using?
What are the nameplate ratings of your UPSs including amps, VA, and W (or kVA & kW)?
What the peak load of your IT equipment in W (or kW)?

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5
reply to joako
Two things.

I have that same beige APC UPS (SU1400RMXLNET is mine) or one very similar. The back of mine even recommends a 20A circuit for full load capabilities. It can run on a 15A circuit but at reduced capacity. I don't want to try and climb back there to get a look at it right now though.

Second, I hope you have some kind of support brackets in the back holding up the back of that UPS? I know from experience it is HEAVY. You only have the TOP screws in place. Gravity will pull against those screws and eventually rip them out or break them. If you only want to do two screws put them in the bottom two holes but honestly with something that heavy I'd put all four in.

Oedipus

join:2005-05-09
kudos:1
It looks like he has the APC brackets in place. The brackets support all of the load, so the screws are there only to keep the UPS from sliding forward.

JoelC707
Premium
join:2002-07-09
Lanett, AL
kudos:5
Hard to tell honestly. If that's the case then yeah that's all you need. I see threads behind the lower holes but that could just be an installed cage nut.