How To Charge Ups Battery. Next power up the UPS and the computer then turn the AC mains power off at the wall. A 10A charger could be used for a battery set up to 120Ah.
If not then that means your UPS battery backup is damaged and may not charge the battery as usual. Switch UPS to battery power and run for as long as possible before draining all battery power. Then consult with user manual and charge the battery for the amount of time that stated in the manual.
The battery should give best performance in 8-10 days.
You can use this trick after every passing year and use your UPS battery for an extra 2 years. 1 UPS charging volts it goes to 139 to 145. 3 Charging starting voltage 119 to 123 V. So now you are familiar with the internal components of the UPS and know how to change the UPS battery.
