I have a Kyoritsu 4120 Digital PSC-Loop tester that suddenly stopped working.
It is used to measure the Ground resistance for an electrical system.
Pictures annexed.
It was working well, but suddenly it stopped and now during measurement shows 1 and nothing else.
The three neon bulbs are working fine and the measurement timings are good.
Anybody has the schematic diagram?
Of course already tested semiconductors, diodes, resistors, fuses.
Thank you