ESV5 Mge/SqD/Eaton/APC desperate for schematic for this obsolete unit!

[Anonymous user]

Now that ESV5 is obsolete and no longer supported, it is time for schematic to be made public.

Does anyone have a schematic?

I have two of these and both recently stopped charging.  New batts and the inverter in them turns on when AC is dropped, so they are worth repairing.

In addition to no charging, when AC applied and first turned on, after the startup routine, the outputs turn on for 200msec under battery inverter power then shut right back off - so it is not usable at all since on AC there is no output, and only output on loss of AC.

Hopefully someone has a schematic?  

[Anonymous user · Accepted solution]

In case anyone else has this issue with this model or any other model, it appears using PWM IC chip (8pin) UC3842/3/4/5 is very common.  The AC is brought into it and it then PWMs the output charging voltage for the batts.  It needs a 35or so ufd cap on osc input pin 7 to START the oscillator;  this cap is often right next to a 2 watt high heat resistor that cooks this cap open.

The esv5 cap is 25ufd,50v,85C, C014.  Suggest if you buy one to get 105C rated one, or do as I did not having one  mount it @ 45degree angle physically away from the heat source.

I replaced this cap and now have a working unit again that went from just -100ma discharging (rest of the unit uses the battery for logic juice) to +.500ma charging.

This learned from an APC rs500 model thread on another forum.