UPS advice

Fishcrazy

Fishcrazy

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I have a PC UPS that I've connected to my return pump in case the power goes off and I am not home. Brand: APC Back-UPS CS 650 I van get the serial number if needed.

The UPS output is 650VA: 220-240V~, 3A, 50-60Hz, 400W.

The pump is only 40W and is the only thing connected to the UPS.

I would've thought that this should be fine for about 2-4 hours of operation, given the small consumption of the pump.

As it is, I only get about 35-40 minutes on a fully charged UPS. I've heard of people getting about 2-4 hours on a similar consumption on UPS's.

Anyone with ideas or experience in this regard that can assist please? I'm not at home during the day and it seems the power outages last between 2 - 3 hours.
 
get a DC pump, or another pump that uses less than 40W
 
hi, 2 things, ups faulty or batteries are shot
you would need to replace them, you can get them tested at any electronics or battery center
 
I agree with @dallasg, probably the batteries that are done. Even so, remember that UPSs are strange beasts and the specs often get misinterpreted.

Example, if you look at the technical specs for this UPS at Buy APC Back-UPS 650, 230V - Technical Specifications and Information | APC

You will find a graph of efficiency vs %load. In your case, the 40W pump is less than 10% of the 650VA of which it is capable, meaning that you are running at somewhere between 80-90% efficiency. In addition to this, any motor (like a pump) driven by a square-wave, or modified sine wave in this case, will also run less efficient than when it is given a pure sine-wave.

I would estimate that your efficiency could be sitting as low as 50%. According to the site above, at 50W, you should get somewhere around 80mins. Divide this in half, due to the 50% efficiency, and you could expect something in the order of 40mins.

Hope that helps explain it a bit :).
 
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Sorry for bumping this thread again but I need some advice on a similar setup. I also bought a 650Va UPS (Proline) but it only runs for ten minutes at a time. I checked the battery status via the USB connection to a PC after a ten minute run and there is still more than enough capacity left - this is further proven by the fact that if I switch the power button off and then back on it runs for another ten minutes.

Now, in the control panel of the UPS I set the shutdown time to the longest possible setting which is 1440 minutes and then fully charged it without any load. It then ran my 18w lights and my 15w pump for an hour before it had started giving warning that the battery was low. I then decided to only run the pump and it then went back to only running 10 minutes a time even though the settings were still in place and the UPS was fully charged again. Any thoughts about this? Does anyone know how to completely disable the automatic shutdown? I've heard that if the load is too low it will automatically shutdown.
 
from my experience on std UPS's (I am in the IT distribution field).... is that the std batteries on these will only last 30-40mins even if you are just running a pump...

Most of the time the guys will build their own type of UPS which they use invertors, 12v car batteries and a tricklefilter.

would suggest a read here....

UPS Buying Guide | Tripp Lite

if there are any questions still. send me a pm and I can drop my UPS suppliers a mail asking for load etc and suggestions.
 
35-40 Mins looks about right with a used UPS running @ 40Watts per hour.

If you looking to run 40W for 2-3Hours you need a 1200va UPS.

Here is a simple calculator.

UPS Selector
 
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Ok, so I've been looking for a cheap solution and came across the "RAMBO AC/DC Battery Operated Air Pump". Since I have a 8G Nano tank I think this might just do the job of oxygenating the tank for extended periods of power outages. Do you think it is worth it? Seems to be a cheaper solution.
 
I have a battery operated air pump, and yes, it works ok for nano systems. I have the boyu tl550, with a sump, and I just drop an air stone in the dt when the power goes...
 
The first link is dead.

Second one I would not use a car battery. A deep cycle battery would last a lot longer. Car batteries are designed to give a lot of power, but cannot be drained below 80%. Their lifespan gets shorten a lot if they drop under 80%. Reason why a battery older than 2 years, and you forgot your lights on. That battery will most likely not make it through the next winter.
 
works now. Their servers might have been down at the time I tried.
 
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