Water pump UPS

[ac_apc]

Hi,

We have a water pump (sump pump) that requires to stay on for as long as possible, in case of power failure. The pump is activated/deactivated automatically according to (heavy) rain-water flow. The pump is rated at 11.5 Amps, 115V, 1 phase.

Power regulation and surge suppression should not be issues but pump continuity during powerstorms is crucial. We are in a major city where power grid is good.

What battery back-up/ups should we get?

Thank you.
Cheers,
ac

[Anonymous user]

I very seriously doubt that a 1500VA UPS will be able to handle the startup current of the pump, which is typically 6 times the normal running current.

On top of that APC dont list the output waveform type so I doubt its true sinewave (like SUA) which you would want for a motor.

Your best bet is to find out the startup current of the pump (under load, not dry) multiply that by your voltage (115) then devide by 0.6, that will give you the approximate VA needed then I would be inclined to add another 30-40% headroom just to make sure.

On top of that you should really have a true sinewave output when the UPS is on batteries so you're not looking at a cheap setup.

[upsguy_apc]

I'd buy something like this. Its designed for exactly what you want. The reviews for this particular model aren't good but I'm sure there are some units out there that may be better.

http://www.amazon.com/Simer-A5000-Hole-Battery-System/dp/B000DZKXC2

Message was edited by: upsguy

[BillP]

i agree you may need a larger UPS such as a 2200 VA model to handle the start up current. FYI, everything EXCEPT Back UPS, J type AV units, and Smart UPS SC output a pure sinewave. the Back UPS/Smart UPS beginning with BE, BX, BR, BP, BN, J type AV models, and SC all output a step approximated sinewave which will not work well with a motor load.

[ac_apc · Accepted solution]

Hi,

We have a water pump (sump pump) that requires to stay on for as long as possible, in case of power failure. The pump is activated/deactivated automatically according to (heavy) rain-water flow. The pump is rated at 11.5 Amps, 115V, 1 phase.

Power regulation and surge suppression should not be issues but pump continuity during powerstorms is crucial. We are in a major city where power grid is good.

What battery back-up/ups should we get?

Thank you.
Cheers,
ac