Any electricians around? What do I need here....

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Situation:

Have a variable speed pump outdoors which I have programmed to run for 30 seconds "Not to exceed 400 Watts" for prime and then slowly settle at runspeed which is under 180 Watts. The pump itself is 240 volt wired, has it's own programming interface and it automatically shuts down if it can not maintain flow or power is cut. It does not lose programming as it has an internal flash drive and reloads time and program automatically. The pump itself is rated at 8 HP but will never run at full power due to programming.

I would like to wire a UPS or battery backup system that would permit it to maintain power for about 5 minutes. Have not found any consumer UPS units that would allow a 240 v connection or simple way to hardwire this into the breaker panel outside. Does such a thing exist ? What do I need ?

Most power outages are just short blips and having a short standby for such a small load (below 400 watts) would save me from having to manually reset the system from an overnight power outage or brownout.
 
I think there are UPS systems that can do what you want, but you do not want to hear the cost.

You could look at a large computer UPS and a step-up transformer. They sell step-up transformers for people who bring stuff from Europe to use in the USA.
 
I'm not an electrician but I know a few things about UPSs.

There are 240 volt UPSs out there, I've ran quite a few of them in a 240v powered datacenter, but you're looking into some pretty high costs compared to consumer UPSs.

I have a 5Kva in all of my IDF (datacom wiring closets) to provide redundant power to the switches since they take forever and a day to boot up. Running on 240V. Those were about $2500 each and I've got 12 of them.

I used to have a 5600 square foot datacenter and ran a 225Kva UPS that was full of car batteries. But, after the servers were outsourced and went to live at a remote datacenter, the localdatacenter was turned into a large meeting room and all the switch stacks were decentralized, they got moved as close to the end users as possible.
 
What facts are off here? 8HP pump, fed by 240 single phase, with a 400W/180W setting?
 
Seems like a programmable inverter drive system on his variable speed pump that controls an 8HP capacity motor, henni can you clarify?
 
Originally Posted By: JHZR2
What facts are off here? 8HP pump, fed by 240 single phase, with a 400W/180W setting?
Should be about 10 amps or so.....
 
Originally Posted By: PeterPolyol
Seems like a programmable inverter drive system on his variable speed pump that controls an 8HP capacity motor


Yes, capacity is made for up to 8 HP at max power and RPM but I've coded the interface for the magnetic drive to ramp up speed very slowly and the pump runs mostly at night and is totally stealth silent, using just 104 to 112 Watts of power based on remote monitoring feedback loop. When it starts running, yes, it has a DC (not AC) motor and can run at any speed depending on code base. Many "regular" variable speed pumps have maybe 4 speed settings -- this unit is infinitely programmable.

Will look into all suggestions.
 
We use to use the 120v to 240 three phase above to run 240v motors and they are infinity variable. You only use 2 legs of the output.
 
What you describe is a variable speed DC motor. and NOT an AC induction motor which is a completely different animal.

In any case if it is standard AC motor UPS systems are NOT designed to startup an AC motor or other Inductive loads for that matter. every AC motor has startup windings and capacitors and an 8 HP motor would need hundreds of amps to startup.

I have seen high frequency AC controllers that can control say the blower fans on roof AC units but no power backups for them as current is too high.

Without more concise technical info this is all a guess. My only recommendation is that if you only need <400 watts why arent you using a small DC motor like the 400 watt ones on electric bicycles to do what you want. ...then the battery backup would be inherent to the design. Are you sure you dont mean .8HP the numbers 400 watts and 8HP don't even come close to making sense.
 
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How about getting two different 120v UPSs, each on a different electrical bus, and then ganging together their output to get your 230? That would be really cheap too
 
Keeping them in phase would be a real SOB if not impossible, unless they were designed for that. I'm no UPS aficionado, so I don't know the extent of what's out there but I've got a couple of legacy APC BackUPS running on car batteries, and they definitely adjust phase on the fly based on the line phase, for a smooth switchover. When being fed by a gas generator, it can really chase the unstable line frequency from the genny.

Maybe all OP needs is an old 230V consumer UPS from Europe/Australia. Should be able to pick up 60Hz with no problem. Finding one with dead batteries should be cake and those little sealed AGM batteries are easily substituted for vehicle batteries.
 
Originally Posted By: JHZR2
What facts are off here? 8HP pump, fed by 240 single phase, with a 400W/180W setting?

Yes 1 HP is 760 watts, at 100% efficiency. 400 W will yield about 1/3 HP mechanical output.

Inverter drives rectify the incoming power to DC then chop it back to AC at the frequency needed by the motor. So the quality of the incoming power isn't very critical.
 
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