UPS Faulty

Discussion in 'General Electronics Chat' started by kagustha, Jun 19, 2011.

  1. kagustha

    Thread Starter New Member

    Jun 10, 2011
    *UPS is working with 500Ah battery of reputed company also it is maintained with correct level and specific gravity. But it is going on charging for almost one day what may be the problem.
    *Give me details about the charge detecting and stopping circuit in UPS and laptops

    Senior Member

    Jun 29, 2010

    you are talking about UPs of 500Ah which is very large current, where are you using this UPS??
    as its current rating is very high it will take many hours to charge it, for backup..
    kagustha likes this.
  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    Take the battery off charge immediately and check the voltage.

    IF the voltage is not over 13.5 volts or more immediately after removing the charger, then you can suspect a shorted cell.(reading 12.5 to 13.5 volts)

    After a few hours rest the voltage will read 12.5 to 13 volts and will appear to be normal. This is the result of the other cells being overcharged. Letting it sit for several days undisturbed will see the voltage reading continue to fall, reaching less than 12.5 volts eventually. This is a SURE sign of a shorted cell. The battery is useless for any type of UPS if this is the case.
  4. #12


    Nov 30, 2010
    You could also measure the charging current and read the specifications of the UPS and calculate whether charging all day is the correct thing to expect.
  5. kagustha

    Thread Starter New Member

    Jun 10, 2011
    why there is shock on metal casing on all two pin electronic appliances like tv DVD player, STB ,LNB,etc., even when there is no direct contact of components (resistors,diodes,capacitors,inductors,transformers,etc.,)?{POTENTAIL DIFFERENCE BETWEEN PHASE AND NEUTRAL IS 216V AND BETWEEN EARTH AND NEUTRAL IS 1V}. Please help me to find the answer:confused::confused::confused::confused::confused::confused: