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DIAGRAM 1
DIAGRAM 2
2.POWER DIODE TEST
K. POWER SILICON CONTROLLED REC- TIFIER TEST
a.Establish the polarity of the ohmmeter leads and set to X10 scale.
b.Connect the ohmmeter positive lead to anode and negative lead to the cathode.
c.Reverse the leads of the ohmmeter from Step b.
d.A shorted diode will indicate zero or an equal- ly low resistance in both directions. An open diode will have an infinite or high resistance in both directions, and a good diode will have a low resistance in Step b and a much higher resistance in Step c.
The SCR must be mounted in the heat sink when making this test.
a. Connect the ohmmeter (set to the X10 scale) leads to the anode and cathode.
b.Reverse the leads of the ohmmeter from Step a.
c.A shorted SCR will indicate zero or an equally low resistance in one or both directions.
d.Establish the polarity of the ohmmeter. Connect the positive lead to the gate and the negative lead to the cathode.
e.An open gate circuit will have an infinite or high resistance. A good gate circuit will read a low resistance, but not zero ohms.
IDEALARC R3R