How can I make cRIO aware if UPS is on Battery Power?

[JimMacD]

Ben

I added pull-up resistors to my test setup because the UPS is a sink (open collector), not a source. i tried attaching the scope to the pin originally, but did not get a response. I figured based on APC's schematic, they used PIN7 on the computer side as V+, so I also should provide a V+ (which I used 5V).

Is it possible that I somehow shorted the Low battery transistor, so it acts as a resistor only? That might explain why my voltage remains constant, but varries as I change the pull-up resistor in the test network.

[Ben_J1]

To be honest I am not sure. I would try TLE's suggestion and seeing if their software is even aware of a low battery. This will tell you for sure if you blew the transistor.