Repairing 48 volt Battery Charger

Thread Starter

Mad Professor

Joined Apr 15, 2009
Good day to you.

I am looking for help and advice regarding repairing a 48 volt battery charger.

I have already pin pointed the fault down to, two failed diodes in the bridge rectifier, from the output of the low voltage transformer.

The output of the transformer is around 60vac.

Here is the details of the dead diodes.

Vrrm = 600V.
Vrsm = 765V.
If(av) = 25A.
Ifsm = 300A.

Instead of me buying two Case-Cathode and two Case-Anode diodes to repair this unit, can I just use the following?

Taiwan Semiconductor
GBPC5010 <Click for datasheet.
Vrrm = 1000V.
Vrsm = 700V.
If(av) = 50A.
Ifsm = 400A.

Thanks for your time.

Best Regards.
Last edited:


Joined Nov 30, 2010
Yep, looks good to me. At power line frequencies, diode selection is pretty simple, and it looks like you've done well. I would only suggest that you write down the original specs in case you have to replace the rectifier again, be sure it has plenty of mass to get rid of the heat it will generate, and check to see if something else killed the rectifier, like a shorted battery.