Can DC pumps mess with UPS back-up batteries?

[islandguy11]

I have a question for the more electronically inclined: I've had problems with several UPS that are connected to my fish tanks in the last year or so, and am trying to narrow down possible causes. The UPS don't outright fail, but start to click off and then back on really quick. Also it doesn't continually do this, it's quite erratic, maybe about every 5-15 minutes.

I have one tank right now it just started to happen again with (800VA UPS is only about 4 months old), which is causing power hiccups to the canister filter on that tank, which isn't good for the motor.

None of the UPS were being over-taxed wattage wise, so I'm just trying to narrow down the causes and wondering something: I kind of recollect these UPS issues starting after I began using (Jebao) DC pumps on my tanks -- could they be messing up my UPS or shouldn't be any negative effect because they're DC?

The one thing I do know is that during longer power outages, and when I have an inverter hooked up to a car battery to power my tanks (and bypassing the by then depleted UPS), the DC pumps make problems (inverter alarm goes off quite soon after connecting) -- I think DC stuff needs a different kind of inverter than the normal ones in that situation, so wondering again if they might not be good for UPS?

 

[Rocksor]

Did the manufacturer state that the UPS has a DC capable output?

 

[islandguy11]

Did the manufacturer state that the UPS has a DC capable output?

Well now that you mention it, it doesn't really say anything to that effect on the box:



So are there UPS that are also capable of DC output or do I need a different back-up solution?

In any case I guess the best test is to first take the DC pump off the UPS and plug it directly into the wall, then see if the on/off clicking stops, gonna do that now.

 

[Rocksor]

Generally APC power supplies output AC power and looking at that specific model, based on the manual, I would say the output is AC due to the row stating AC surge protection for all sockets.

https://www.apc.com/salestools/CLII-9ZSLKS/CLII-9ZSLKS_R0_EN.pdf

 

[epond83]

Battery back ups usually don't output a true sine wave. I wonder if the power supply for the pump is causing trouble with that.
I would try and look to the pump manufacturer and see what they say about running from a UPS.
As a side note this is inefficient, conveteting dc to ac in the UPS, then the power brick on the pump converts ac to DC. I think the ecotech back ups are dc straight to the pump so they are more efficient.

 

[islandguy11]

Battery back ups usually don't output a true sine wave. I wonder if the power supply for the pump is causing trouble with that.
I would try and look to the pump manufacturer and see what they say about running from a UPS.
As a side note this is inefficient, conveteting dc to ac in the UPS, then the power brick on the pump converts ac to DC. I think the ecotech back ups are dc straight to the pump so they are more efficient.

Thanks for good input epond83! Although I don't totally understand it all, yes it could be a sine wave issue. Unfortunately with Jebao it's just about impossible to get any answers to emails or real customer service.

I would love to have an Ecotech battery but they're really hard to find here (maybe only a couple of saltwater shops has them) and really expensive -- maybe some day in the future.

But for now last night I unplugged the dc pump from the UPS and plugged it directly into the wall instead -- the on/off clicking with the UPS has stopped, so it was definitely causing an issue.

Anyway I'm going to replace that dc pump soon with a regular pump I have on the shelf, then hopefully should be no problem to put it back on the UPS.

 

[fishdance]

I had a few issues with Automatic Transfer Switches. Both commercially made and custom made. Occasionally when initiating, they would fry the inverter creating unreliability and mounting cost of equipment including additional redundant backups.

In the end I removed the ATS completely by using a float charger to keep deep cycle batteries full (but not overcharged) while they constantly ran an inverter which powered my aquarium equipment. If a power fail occurs, the batteries continue to run the inverter for 3 days. I hope power would resume by then or I would switch to a generator (manually).

Your UPS unit is essentially a combined ATS and battery pack.

So not able to answer your query, just offering a reliable alternative to emergency power.