This is a Test arrangement for Leakage Testing of Diodes on Reverse Bias. The leakage current indicates the ability of the diode to withstand higher voltages. An AutoTransformer or Variac can be used to vary the test voltage. Even Plastic capacitors can be tested for leakage this way.
High Resistance Indicator - del50004
Safety Precautions -
Use a Isolation 1:1 transformer for safety. This circuit has to be enclosed in a insulated cabinet. A Jig or Acrylic Safety Plate with clamp can be used to connect the diode. The voltage is only applied as long as a Mains two way push switch is pressed. This adds to the safety.
Build a DMM or Digital Multi Meter
Caution Instruction -
Use this with Low voltages like 24V AC for Learning. Do not Use it with High Voltage AC. If you are learning, first work with other circuits using batteries or Low Voltage Mains Adapters.