Hello all, I have a NIFE Powertronic DC Battery bank charger that my company uses as a DC source for the commissioning of Load centers/ a DC source to cheat in power. It was recently tagged out saying that there was to much of an AC component on the output and it may lead to damaging energized equipment. Initially all a plugged the device in and measured the DC which was around 137 VDC then the AC which was 104 VAC!!! Right away i thought that this was the result of a faulty SCR. In our shop we have a second charger of a different model and I measured 2 VAC on the output further leading me to believe that the SCR was the issue. After changing the SCR the output still contains the 104 VAC component and I was wondering if anyone could give me any ideas on what may be causing this. I have attached pictures of the charger, nameplate, SCR we replaced and a rough sketch of what the wave looks like can be seen drawn on a piece of paper on the front of the device.

Any information would be AWESOME!
Thank you for your time.

 

In your pictures of the box I can't see any large capacitors which would smooth out the ripple on the output. If there are indeed no such capacitors then I don't see how the output could have no AC component.