SUA1500 makes noise even when it's off

[Anonymous user]

Hello,

I have a SUA1500I and I never noticed any kind of inconvenience, except that I had to replace the batteries some months ago because they had exhausted their useful life, what is a normal process.

But now I have a doubt that is bothering me a little.

I use the UPS with my Home PC, where I have a room (home office) for all those things.

Right now we are doing some painting and remodeling at home and I was forced to move the PC to the same room where I sleep for two weeks.

Since I did it, I noticed that even if the equipment is off, it still makes a low sound always. It seems like the fan running at low speed.

Only when I unplug the equipment from the power outlet, after about 5 minutes, it is heard as the noise of a relay (it seems) and finally it is in total silence.

Probably that is the normal operation of the equipment, maybe I never noticed it because I did not have it in the same room where I sleep.

As an additional information, I confirm that the UPS batteries are 100% charged, so it's not making noise because the batteries are charging.

Please, I will appreciate very much if some other user of this equipment or technician of APC could confirm to me if that noise is normal.

I still have to sleep with that equipment in my room for 10 more days and I do not know if it is working normally or if it's failing and it's dangerous.

Thanks a lot for your help and comments.

[BillP · Accepted solution]

Hi Rodrigo

The following information from one of our FAQs should put your mind at rest 

Later "SUA" model units utilize a 2 Speed fan. On these units the fan will always be on in low speed mode, and will switch to high speed mode should one of the following events occur:
1. The UPS is on battery.
2. The UPS is charging the battery.
3. The UPS has a load greater than 75%.
4. The internal temperature of the UPS has reached greater than 104 degrees F (40 degrees C).

Regards

Matt

[Anonymous user]

Hi Matt!

Yes, I had read that information, but it had not been clear to me that the fan was also working on low speed mode when the equipment is turned off.

Perfect! Then it's working normally.

Thanks a lot for your answer. 😃