APC CS500 remains off after long power outage

[BillP]

Title says it all. New battery all is in perfect condition. Light load. I test UPS by pulling the cord out from the wall, it works perfectly and supply power for 90 minutes. As I calculated battery should be near the end, I reconnected the power cord.

But, it seems, that after being cut off from the power for 5 hours where battery got empty, UPS did not return to powered on state! Hence, power returned but APC Back-UPS CS500 left all of the connected devices dead!

But, this would be impossibly stupid since the reason for existance of any UPS is to always provide the power to the connected devices, and never cut them off. After all, It is called: Uninterruptible power supply! After being powered on by the button, it returned the power to the connected devices.

Or am I expecting that mistakenly since I am used to big and good UPSes? This is our sole tiny UPS.

Is this APC Back-UPS CS500 broken or just plain unusable as UPS by design?

[BillP]

Hi,

Do you have PowerChute configured or any other OS shutdown software? With PowerChute the UPS will be told to power down prior to running completely out of battery power. Then when AC is restored it will power on which in turn should cause the PC to restart. NOTE: The BIOS of the PC will need to be configured to power on when AC is restored.

If the UPS battery drains completely the UPS will require user intervention to power it back on. 

[BillP]

On 9/10/2019 11:37 AM, Bill said:

If the UPS battery drains completely the UPS will require user intervention to power it back on. 

Apparantly that is the problem. So, this is normal behaviour. There is no PC connected to it, just a router, a switch and a modem.

So, each time it is left without power say 6 hours and it can battery popwer devices for say 2 hours, it will not return to the On state without an user intervention?

I have quite few bigger UPS-ses and each will return to full power on state on its own once the grid is back.

Can it be somehow tricked into returning to PowerOn state after its battery is emptied completely? I need an UPS that will work as there may not be anyone to power it back on.

[BillP · Accepted solution]

What will happen if incoming power is cycled AGAIN AFTER battery went empty and then the power returned and filled it up. UPS will be off.

Will removing the power from it for few seconds and returning power on restore UPS to On state or leave it in Off state? Now its batterry is full.