Emerson Network Power (Closet Class UPS for Edge Switches)
Manufacturer Liebert Corporation
Liebert UPStation GXT
Configure an advanced alert trigger condition to notify you when upsSecondsOnBattery is NOT equal to 0. This is when the UPS switched to Battery Back Up.
In that same alert configure the reset condition to notify you when upsSecondsOnBattery IS equal to 0. This is when inline power has returned.
To display the custom poller you will have to add it to your node details page in NPM.