Work Description---------------------UPS A1 battery charger failure alarm, after the supplier’s on-site inspection and confirmation, the battery charging control board needs to be replaced.Power resource A to IT devices will be running on by-pass, replace the battery charge control board. There will be potential risk of half power redundancy loss in case of utility power suspension. UPS B1 and STS mounted on each rack will be supporting comms room/closet during that time. After completing UPS A1 maintenance, switch back to UPS power supply and resume power supply.