BR1500G-GR with BR24BPG drained in 1 minute

[JT5]

Slightly old (3-4 years) UPS kit but battery status shows 'Normal' and Self Test is 'Passed'.

Remaining runtime is shown as roughly 90 minutes. 

Still, this is what happens when mains power is lost (data from a quick test today):

Time (hh:mm:ss)	Input Line Voltage (VAC)	Battery Voltage (VDC)	Battery Charge (%)	UPS Load (%)
09:52:09	238.0	26.4	17	28.0
09:51:49	0.0	21.8	28	24.0
09:51:29	0.0	22.9	54	29.0
09:51:09	238.0	27.2	100	26.0

Just bad/old batteries (both UPS and external battery unit) or something else?

[Teken]

The average service life of the RBC is 2-5 years based on usage, temperature, and environmental conditions.

Its more than likely all the RBC are end of life and need to be replaced as the test you performed affirm the same.

Questions Ask . . . 👍

[Keertiraj]

It's clearly a sign of bad battery. you can see the battery voltage is dropping drastically when on load. so change battery.