Filter
Top Products
D-10
TROUBLESHOOTING
D-10
5. An open gate circuit will have an infinite or high
resistance. A good gate circuit will read a low resis-
tance, but not zero ohms.
BATTERY TEST
Check the batteries by shorting leads (A) and (C), then
close switch SW-1. Replace batteries if voltage is less
than 3 volts.
SCR TEST
1. Isolate SCR to be tested by disconnecting gate
leads from the terminals on the P. C. Board. (Do not
remove SCR from the heat sink.)
2. Connect SCR into the test circuit as shown (A) lead
to anode (C) lead to cathode and (G) lead to the
gate.
3. Close switch SW #1 (switch SW#2 should be open);
voltmeter should read zero. If the voltmeter reads
higher than zero, the SCR is shorted.
4. With switch SW #1 closed, close switch SW #2 for
two seconds and release. The voltmeter should
read 2 to 2.5 volts before and after switch SW #2 is
released. If the voltmeter does not read, or reads
only while SW #2 is depressed, the SCR is open or
batteries are defective (repeat Battery Test
Procedure).
5. Open switch SW #1, disconnect the gate lead (G)
and reverse the (A) and (C) leads on the SCR.
Close switch SW #1. The voltmeter should read
zero. If the voltage is higher than zero, the SCR is
shorted.
E500
DIAGRAM 1
DIAGRAM 2