Sharp R-930AW Test Procedures, Component Test, Letter, E Secondary Interlock Switch Test

	R-930AK
	R-930AW
	TEST PROCEDURES
PROCEDURE	COMPONENT TEST
LETTER
	If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads and
	check for short or open between the terminals using an ohmmeter.
	Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate continuity
	for a short time and should indicate approximately 10 MΩ once the capacitor is charged. If the above is
	not the case, check the capacitor with an ohmmeter to see if it is shorted between either of the terminals
	and case. If it is shorted, replace the capacitor.

ESECONDARY INTERLOCK SWITCH TEST

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

FPRIMARY INTERLOCK SYSTEM TEST

DOOR SENSING SWITCH

Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch, the meter should indicated 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.

PRIMARY INTERLOCK RELAY

Disconnect two (2) wire leads from the common (COM.) and normally open (NO) terminal of the primary Interlock relay (RY2). Check the state of the relay contacts using a ohmmeter. The relay contacts should be open. If the relay contacts are closed, replace the relay itself.

GMONITOR SWITCH

Disconnect the oven from power supply.

Before performing this test, make sure that the secondary interlock switch and the primary interlock relay are operating properly, according to the above Test Procedures. Disconnect the wire lead from the monitor switch (NC) terminal. Check the monitor switch 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 lower 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.	N.C.
If improper operation is indicated, the	MONITOR SWITCH
switch may be defective. After testing	COM.
the monitor switch, re-connect the wire	SCREW DRIVER
lead to the monitor switch (NC) termi-
nal and check for continuity of monitor

circuit.	SECONDARY
	INTERLOCK	OHMMETER
	SWITCH

HBLOWN MONITOR FUSE

If the monitor fuse is blown when the door is opened, check the primary interlock relay, secondary interlock switch, door sensing switch and monitor switch 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 RELAY, SECONDARY INTERLOCK SWITCH, DOOR SENSING SWITCH AND MONITOR SWITCH FOR PROPER OPERATION.

If the monitor fuse is blown by improper switch operation, the monitor fuse and switch must be replaced with "monitor fuse and switch assembly" part number FFS-BA012WRK0, even if the monitor switch operates normally. The monitor fuse and switch assembly is packed with 20 ampere fuse and switch.

ITEMPERATURE FUSE TEST

A continuity check across the temperature fuse terminals should indicate a closed circuit unless the temperature of the magnetron reaches approximately 302˚F (150˚C). If the temperature fuse has opened, replace the temperature fuse.

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