Last week my UPS got repaired, Its classic 600VA Ups , the problem is when the main power is on it gives output and when main is off then the UPS gone to off , battery power is not consumed , the battery is 100% at good condition , can u support me , and i think a problem in relay and i changed two relay but the problem still exists , if i turn on the ups at battery power its getting turned on and immediately going to off !!! kindly support me to repair it , battery is working good with other UPS, problem is with the UPS