ISECONDARY INTERLOCK SWITCH TEST

TEST PROCEDURES

PROCEDURE

COMPONENT TEST

LETTER

 

ISECONDARY INTERLOCK SWITCH TEST

1.Disconnect the power supply cord.

2.Open the drawer and keep it open.

3.To discharge high voltage capacitor, wait for 60 seconds.

4.Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch. The meter should indicate an open circuit with the drawer open and a closed circuit with the drawer closed. If improper operation is indicated, replace the secondary interlock switch.

5.Reconnect all leads removed from components during testing.

6.Reassemble the unit.

7.Reconnect the power supply cord.

8.Run the oven and check all functions.

JSTOP SWITCH TEST

MMD24S

MMD24B

STOP SWITCH

1.Disconnect the power supply cord.

2.Open the drawer and keep it open.

3.To discharge high voltage capacitor, wait for 60 seconds.

4.Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch. The meter should indicate an open circuit with the drawer open and a closed circuit with the drawer closed. If improper operation is indicated, replace the stop switch.

5.Reconnect all leads removed from components during testing.

6.Reassemble the unit.

7.Reconnect the power supply cord.

8.Run the oven and check all functions.

NOTE: If the stop switch contacts fail in the open position and the door is closed, the cooling fan motor, stirrer motor and oven light will be activated by RY1.

KMONITOR SWITCH TEST

1.Disconnect the power supply cord.

2.Open the drawer and keep it open.

3.To discharge high voltage capacitor, wait for 60 seconds.

4.Before performing this test, make sure that the secondary interlock switch, according to the above Switch Test Procedure. Disconnect the wire lead from the monitor switch (COM) terminal. Check the monitor switch operation by using the ohmmeter as follows. When the drawer is open, the meter should indicate a closed circuit.When the monitor switch actuator is pushed by a screw driver through the lower latch hole on the front plate of the oven cavity with the drawer 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 and both the monitor switch, plus fuse will need to be replaced. After testing the monitor switch, reconnect the wire lead to the monitor switch (COM) terminal and check the continuity of the monitor circuit.

5.Reconnect all leads removed from components during testing.

6.Reassemble the unit.

7.Reconnect the power supply cord.

8.Run the oven and check all functions.

MONITOR

SWITCH

(BLK) JSTOP SWITCH TEST

(RED)

Ohmmeter KMONITOR SWITCH TEST

(BRN,GRY)

(BRN,BLK)

SECONDARY

INTERLOCK

SWITCH

Screw Driver

17

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Sharp MMD24S, MMD24B Test Procedures, Letter, I Secondary Interlock Switch Test, J Stop Switch Test, K Monitor Switch Test