How did you keep the CPE on that long? My UPS ran for about 15 - 20 minutes and it turned itself off, had to turn it back on and then after 10 - 15min it turns off again.
Set it to setting to run as long as possible, battery is not flat but it turns off. Replaced the batteries after stage 4 load-shedding earlier in the year.
This is what I use.
APC Back-UPS 1400VA, 230V, AVR, IEC Socketswww.apc.com
What you using?
sorry for only getting back now i use one of these below and a old 12 7ah battery bought a new 12v 9ah this week already replaced it and now it keeps my cpe and wifi router the whole load shedding will test later to see how long it will last