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Sir Sparks
Sir Sparks, President/Owner/ Master Electrician
Category: Electrical
Satisfied Customers: 2532
Experience:  US State Certified & UK Electrical Contractor for all electrical fields/disciplines
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I need backup power sources for my sump pump. I dont want

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I need backup power sources for my sump pump. I don't want a battery-backup sump pump, but would prefer to power my existing pump when the power goes out. I know you need an inverter, charger, automatic transfer switch and battery source, but i can't find the right combination. What do you recommend?
Are you on well water or city water
Customer: replied 7 years ago.
city, but i would prefer not to use the water backup option.
The only 2 ways that are possible are battery, or a venturer type backup pump, which is used by water pressure. I can move this question to see if a electrician can tell you if it is possible to do. Just let me know..

Edited by Todd on 4/2/2010 at 3:31 AM EST
I have requested just answer to have this question moved to electrical, we will see what happens.
Customer: replied 7 years ago.



What size in watts is the pump you wish to power?

How long do you wish it powered for?

Customer: replied 7 years ago.
I have a Zoeller Mighty Mate 53, which has a 1/3 hp motor and draws 9.8 amps. I believe the watts is 300 volts steady, but i haven't found a definitive answer. As for runtime, I am looking for at least six hours, but a sump pump seldom works nonstop. It usually discharges for 10 seconds every minute or two at the most.

You have obviously investigated direct battery powered pumps from your first comments and decided not to go that route. A second consideration would be to add a second pump that is ONLY fed from the inverter and battery pack that would most likely be less expensive than purchasing and installing an Automatic Transfer Switch! How do feel about this?


Also I presume your pump is 120 volt?

9.8 amps is high for a 1/3 HP 120 volt pump !

Customer: replied 7 years ago.
I am considering the AIMS 1500 watt with battery charger, power inverter and transfer switch, which you can find at Would this be appropriate for my needs if i hook it up to a 12V deep cycle marine battery from Sears?
I will check out the specs and get back with you.

OK, The AIMS PWRIC1500W inverter with 1200 watts continuous and 2,500 watts peak is suitable for a normal 1/3 HP sump pump.


A normal 1/3 HP pump will draw approximately 5 amps at 120 volts or 600 watts. and a start up load of about 300% should be allowed for to enable starting. This amounts to 1,800 watts and this inverter will deliver 2,500 watts Peak.


Now we hit a problem; Aims is stating that it's pump is 9.7 amps or double what is normal. I am quite sure that this is Advertising BS as they think (Just like vacuum cleaners) Higher amp motors sound more powerful to Joe Public so they use short term Max Amps and not the true sustained amps. The real fact of the matter is that an expensive and therefore efficient motor will follow certain inescapable laws.

1 HP is 746 watts, 1/3 HP is 249 watts or 2 amps. once ineffiences have been alowed for then 4 to 5 amps is reasonable but NOT 9.7 amps.


I searched their website and nowhere does it state TRUE amps. I strongly suspect this inverter will be fine to operate this Zoeller pump, but with the info they supply I cannot guarantee it. Yet purchasing a larger inverter would be very expensive.


I suggest you contact Zoeller Tech Support and ask for the REAL running amps (Anything up to 7 amps will be fine) or invest about $100 on a clamp on ammeter to test what your pump really draws.

Edited by Sir Sparks on 4/2/2010 at 1:08 PM EST
Sir Sparks, President/Owner/ Master Electrician
Category: Electrical
Satisfied Customers: 2532
Experience: US State Certified & UK Electrical Contractor for all electrical fields/disciplines
Sir Sparks and other Electrical Specialists are ready to help you

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