Battery backup - UPS

[FishFish]

Any recommendations on UPS units to keep return pumps going during power outages? I use a larg-ish APC battery unit to keep an 85watt return pump going, and it does ok. I have a smaller unit on a Fluval 406 canister, butthe pump won't stay on once it switches to battery. The pump pulls only 7 watts. I've tried a couple of different UPS' on it, designed for desktop computers, and none of them will keep that pump going.

Thoughts?

ff

 

[zombie]

What happens if you unplug it and plug it back in while on battery power? Does it turn on or no? If it doesn't start back up, the problem is 3rd harmonic saturation, which can only be resolved by purchasing a UPS that is marketed as a "pure sine wave output" with a THD of less than 5%.

 

[FishFish]

Sounds like you've seen this before. . If I unplug it from the battery and then plug it back in to the battery it still doesn't work. I can hear it's trying to start but it's like it doesn't get enough juice to start going.

Even when hen I plug it back into regular power, it has to sit for a couple of minutes unplugged before it will work. Again, it tries to spin, but can't get up to speed. After sitting a couple of minutes, I plug it back into regular power and it works fine.

Only seems eps to be this one pump I have a problem with. The Sicce, Jebao, and maxijets all work fine on UPS.

Thoughts?

ff

 

[zombie]

The issue lies within the pump itself. The fact that it needs to sit for a few minutes leads me to believe that the issue has nothing to do with the power quality provided, but rather that the pump easily stalls. One thing I would try before spending a bunch of money on a new UPS is to replace the impeller inside the canister filter. True sine wave UPS are about twice the price of a voltage step type.