Testing the Power Supply

By Anonymous -
After the capacitors were reformed I put them back in the supply. The plug was changed to a normal 15A 120V plug (might need to be changed to a 20A plug in the future). Changing the plug proved to be more of a challenge then anticipated as the color of the wiring was confusing. I finally decided green was ground, black was hot, and white was neutral.

The jumpers on the transformer were checked to make sure they were set for 120V and 60Hz.

When powering on the supply I did not have an ammeter handy to measure AC current, and the one I eventually found had two blown fuses...

A variac was used to slowly power up the supply. The power supply fan and the case fans kicked in and sounded fine... loud, but fine. I thought things might be OK until I saw smoke coming up from the left corner of the supply. The 0.1Ω shunt resistor had burned up on the G824 module. This needed to be replaced.
 
Below is the replacement. The EE shop on campus only had radial-leaded and not axial-leaded, but nothing a little jumper couldn't fix.



More testing of the power supply to come, along with front panel testing/cleaning, and installed options.







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