Maintenace on 20 KVA UPS

[tom baker]

I now have the responsibility for a 20KVA 3 phase UPS, used for critical loads in a vechicle tunnel (lighting, controls, Fire alarm, etc). The manufacture says there is no need to operate the UPS under load for a periodic test, say monthly for 30 minutes, as the UPS has very good battery managment.
Whats the recommendation of others who work on/maintain similar UPSs? I do have a service contract with the manufacture for a yearly battery service and inspection.

 

[Dweeber]

I am unsure if I can be of much help...I work on larger KVA UPS units.

Pretty much all recommendations for maintenance and intervals are specific to the manufacturer of the battery. Our particular UPS(s) have different battery strings of varying manufacturers, thus small differences do occur.

We are scheduled for quarterly battery termination inspection/torque and interconnection resistance testing.

Also, are these cells of a flooded electrolye type? If so, checking electrolyte is a must. If VRLA, well then not much can be done other than visual inspection.

We perform battery string capacity tests roughly every two years, until the battery capacity is roughly 80% of original, then we test annually. I believe this is an IEEE recommended practice.

Hope this make sense,

D.