SMART-UPS 750

[roberson.souza_apc]

This was originally posted on APC forums on 3/27/2016

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Hello everyone!

I own a Smart-UPS 750 SUA750RMI2U which I've tried many times to communicate using a Windows XP 32 bits, but when I access the Device manager from windows, it shows the UPS as a Unknown Device. I've searched on the web but coudn't find any specific driver to solve my problem. The thing is that I had the same model of UPS installed in this machine, but had a problem and so I had to replace it by another one. Before doing it, the computer was able to communicate with the UPS and when there was a power failure, the UPS managed to shutdown the computer properly. Now it doesn't happen anymore, so I guess it can be related to the fact that the computer cannot communicate with the nobreak via Powerchute properly (in fact it can't find any device). Any hint of what is happening?

Since now, thanks a lot for the support.

[BillP · Accepted solution]

This reply was originally posted by Bill on APC forums on 3/28/2016

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Hi,

Stop the PowerChute service then disconnect and reconnect the USB cable. Open device manager and go to Human Interface Devices you should see American Power Conversion USB UPS. If that is not visible right click on Human Interface Devices and select scan for hardware changes. If the American Power Conversion USB UPS is still not visible after scanning for hardware changes then there is an issue with either the USB cable, USB comm in the UPS is bad, or the is an issue with USB on the system. 

To test USB comm on the UPS attach the UPS to another Windows system and check to see if it is discovered. You can also reset the UPS by following these instructions.

1) Turn off and unplug UPS from wall
2) Press and hold the OFF button again
3) You may see a quick flash of the LED's and you should hear an audible "click" from the UPS.
4) Plug UPS back into the wall and turn UPS back on