Using a Uninteruptable Power Supply (UPS) small grow?

Hey folks

I'm looking for information about whether I can use a UPS (lets say 600w) with a 250w hps digital ballast and timers for fan. It's a cabinet grow within a metal cab and I thought the 3-prong plug would ground the cabinet?

I found this post on grasscity: http://www.thcfarmer.com/forums/f8/connecting-ballast-ups-uninterupted-power-supply-5380/index2.html
and these on RIU: https://www.rollitup.org/indoor-growing/6478-ups-no-not-delivery-service.html , https://www.rollitup.org/grow-room-design-setup/148073-uninterruptible-power-supply-ups-lights.html

Anyknow know more about this?

What were you wanting to know about them? It will just keep your equipment on for a little while if the power flickers. Prob not any longer than a half hour tho