GE JKP18 Series, Technical Service Manual

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Interlock System Test
1. Remove the oven and discharge the capacitor.
2. Check the 20-amp fuse for continuity and
proper size. Do not use any other fuse or size
except 20 amp (314 type or ABC type).
3. Remove one monitor switch lead to isolate the
switch. Check continuity of switch with door
open and door closed.
• Door closed: infinite ohms
• Door open: 0 ohms
4. Reconnect the switch leads
5. Test the circuit operation:
a. Connect a temporary jumper across relay
contacts, primary interlock, and
door sensing switch to simulate shorted
switch contacts.
b. Connect the ohmmeter (Rx1) across the
line terminals of the appliance cord.
Continuity must show:
• Door closed: Some ohms
• Door open: 0 ohms
c. Remove the 20-amp fuse - circuit must
open (infinite ohms). If not, check wiring of
monitor and interlocks.
6. After testing is complete, remove temporary
jumper leads from interlocks and relay and
reconnect switch leads.
7. Replacement of any parts or monitor circuit
requires repeating this entire test procedure.
Interlock Adjustment
Warning: A microwave leakage test must be
performed any time a door is removed, replaced,
disassembled, or adjusted for any reason. The
maximum allowable leakage is 4 MW/cm
2 .
The latch board is adjusted for door fit and switch
operation.
1. Place the key panel in the service position.
2. Loosen the latch-board mounting screws at
the vertical flange.
3. Adjust the latch board for proper switch opera-
tion and door fit. Retighten screws.
nents, except the oven lamp. A cook cycle cannot
take place until the door is firmly closed, thereby
activating the interlock switches.
• Interlock Monitor
This switch is intended to render the unit inopera-
tive by means of blowing the fuse when the con-
tacts of the primary interlock switch and power
relay fail to open when the door is opened.
• Door Sensing (Secondary Interlock)
This switch and the primary interlock switch will
interupt the circuit before the door can be opened.
Primary Interlock Test
1. Remove the oven and discharge the capacitor.
2. Place the control panel in the service position.
3. Check continuity between switch terminals.
Normal readings are as follows:
• Door closed: 0 ohms
• Door open: infinite ohms
Door Sensing Switch Test
1. Remove the oven and discharge the capacitor.
2. Place the control panel in the service position.
3. Check continuity between switch terminals.
Normal readings are as follows:
• Door closed: 0 ohms
• Door open: infinite ohms
Monitor Switch Test
1. Remove the oven and discharge the capacitor.
2. Place the control panel in the service position.
3. Remove one monitor switch lead to isolate the
switch.
4. Check continuity between switch terminals.
Normal readings are as follows:
• Door closed: infinite ohms
• Door open: 0 ohms