SUA1500 & odd behavior?

[BillP]

Hi,

I own two SUA1500 that were purchased new. I've used both for awhile and they're both on their original batteries (~ 2 years old). Please read my questions in detail.

Question (1): When powering on a PC and monitor, which is the only hardware attached to SUA1500#1 which itself is currently online, what would make the ON BATTERY light of the SUA1500 flick on and the UPS go to battery for a second? This will occur each time the hardware (e.g., PC) attached the UPS is turned on. I've measured the watts drawn by the hardware attached to the UPS, both during power on and idle, and it's under half the max capacity of the UPS. Even at load the watts drawn by the hardware are under the max capacity of the UPS.

Question (2): When powering on two PCs and two monitor, which is the only hardware attached to SUA1500#2 which itself is currently online, what would make it completely shut down to the point where all lights on the UPS go dark and I have to hit the TEST button to power it back on? This will not consistently occur. I've measured the watts drawn by the devices attached to the UPS, both during power on and idle, and it's under the max capacity of the UPS. Even at load the watts drawn by the hardware are under the max capacity of the UPS.

For the above tests neither a power strip or surge protector are being used. The UPS is connected directly to a wall outlet (15A) and only other devices on the circuit during the tests are a couple of ceiling lights.

Thank you.

[BillP · Accepted solution]

clarkson wrote:
The UPS should not shut down like unless it tries to go to battery and the battery is bad OR the UPS thinks there is a short. If you have a scenario like above, and it tries to go to batt on a bad battery, it will turn off. With the load turned on and the UPS online, if you unplug the UPS does the battery give you a few minutes of runtime at least? If so, you can probably eliminate that. Another possibility is that the UPS thinks there is a short and shuts off. I would switch the load between the two units and observe the behavior.

Unfortunately I had to dismantle one of the machines so I can't test that machine at load any longer. The battery in the UPS that went dark does hold a charge and when it's disconnected from the wall socket it will run connected devices for a time. You're the second person to mention a short.

Is there any way I can test the UPS from my end to make sure it isn't faulty? I've run the self test, which is run when the UPS is powered on, but that's about it.

Thanks.