Well how long you had use the battery already if it more than 3 yrs it time to change a new one the time of the lifespam of the battery it startin to decae or the battery is bad. replace a new battery and test it up.. i sugguest you to on the power of the ups all the time. no need to worry for the equiment to be gettin spoil.. ups is able to with stand the unstable power and to protected the equiments.. the liabitily of the ups is high.. if you keep turn off the ups you may not a ware that u are not fully turnin off the ups that cause of the internal chargin may still charging and dis discharge and cause the life spam of the battery to dead faster.. that becoz the battery after u install into the ups it start to charge and discharge 300 cycles so it juz nice to prolong till 3 yrs but if you turning off and on it will speed up the cycles..