R-22JT
14
H
BLOWN MONITOR FUSE TEST
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge two high voltage capacitors.
4. Before performing this test, make sure that the secondary interlock switches (1), (2) and the primary
interlock relays RY2, RY3 are operating properly, according to the above Switch Test Procedure.
Disconnect the wire lead from the monitor switches (1), (2) (COM) terminals. Check the monitor
switches (1), (2) operation by using the ohmmeter as follows. When the door is open, the meter should
indicate a closed circuit. When the monitor switch actuator is pushed by a screw driver through the
upper latch hole on the front plate of the oven cavity with the door opened (in this condition the plunger
of the monitor switch is pushed in), the meter should indicate an open circuit. If improper operation
is indicated, the switch may be defective. After testing the monitor switches, reconnect the wire lead
to the monitor switch (COM) terminals
and check the continuity of the monitor
circuit.
5. Reconnect all leads removed from
components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after
the outer case is installed.
8. Run the oven and check all functions.
of the switch. The meter should indicate an open circuit with the door open and a closed circuit with
the door closed. If improper operation is indicated, replace the door sensing switch.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
NOTE: If the door sensing switch contacts fail in the open position and the door is closed, the blower
motor, stirrer motors and oven light will be activated by RY1.
PRIMARY INTERLOCK RELAY (RY2, RY3)
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge two high voltage capacitors.
4. Disconnect two (2) wire leads from the male tab terminals of the Primary Interlock Relay RY2 and/
or RY3. Check the state of the relay contacts using a ohmmeter. The relay contacts should be open.
If the relay contacts are closed, replace the circuit board entirely or the relay itself.
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
G
MONITOR SWITCH (1) AND/ OR (2) TEST
SCREW DRIVER
MONITOR SWITCH (2)
OHMMETER
MONITOR SWITCH (1)
LATCH HOOK
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge two high voltage capacitors.
4. If the monitor fuse is blown when the door is opened, check the primary interlock relays RY2, RY3,
secondary interlock switches (1), (2) and monitor switches (1), (2) according to the "TEST
PROCEDURE" for those switches before replacing the blown monitor fuse.
CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE, TEST THE PRIMARY INTERLOCK
RELAYS, SECONDARY INTERLOCK SWITCHES, DOOR SENSING SWITCH AND MONI-
TOR SWITCHES FOR PROPER OPERATION.
If the monitor fuse is blown by improper switch operation, the monitor fuse and monitor switch must
