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3.4 Testing transistor leakage current (
ICEO
)
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the desired I
CEO
range (PNP or NPN).
3. Connect the transistor straight into the transistor socket. The holes of the socket are marked E, B and C for
emitter, base and collector.
4. Read the leakage current (I
CEO
) of the transistor straight off the display. The unit of measurement is µA.
3.5 Testing of SCRs/ thyristors (good/bad)
1. Switch on tester (move on/off switch to "ON" position).
2. Turn rotary switch to the position SCR.
3. Insert the SCR straight into the transistor socket. The holes of the socket are marked A and G for anode and
gate and K for cathode.
4. If the SCR is good, the display should show "000".
5. Turn the rotary switch briefly to NPN hFE and back to the SCR range. If the SCR is good, the display should
now show "1" (overrange ).