ACP XpressChef JET514A, Service Manual

Page: 19 / 41

19
COMPONENT TESTING
Illustration Component Testing Results
Thermal Cutouts
Disconnect all wires from TCO.
Measure resistance across
terminals.
Cavity Thermal Fuse .......................................
Magnetron TCO ..............................................
Open at 104° C (219° F
).
Open at 138° C (280° F) and
Closed at 82° C (180° F).
Diodes
Discharge Capacitors
Remove diode lead from capacitor
and connect ohmmeter.
Reverse leads for second test.
Infinite resistance should be
measured in one direction and
50KΩ or more in the opposite
direction.
NOTE: Analog meter must
contain a battery of 6 volts
minimum.
MT2
MT1 GA TE
Triac
Disconnect wires to triac.
Measure resistance from:
MT1 to MT2 ....................................................
MT1 to Gate ....................................................
MT2 to Gate ....................................................
All terminals to ground ....................................
Caution - Do not operate oven
with wire to terminal MT2
removed.
Infinite.
Approximately 60 Ω or more.
Infinite
Infinite.
Capacitor
Discharge Capacitors
Remove wires from capacitor
terminals and connect ohmmeter,
set on highest resistance scale to
terminals.
Also check between each terminal
and capacitor case.
Between Terminals: Meter
should momentarily deflect
towards zero then return to over
5 MΩ. If no deflection occurs, or if
continuous deflection occurs,
replace capacitor.
Terminal to Case: Infinite
resistance.
ALWAYS USE CORRECT SIZE
Snubber Assembly
Disconnect wires to snubber.
Measure resistance across terminals ..............
Infinite.
Magnetron
Discharge Capacitors
Remove wires from magnetron and
connect ohmmeter to terminals. Also
check between each terminal and
ground.
Between Terminals: Less than 1
Ω.
Each terminal to ground
measures Infinite resistance.
NOTE: This test is not
conclusive. If oven does not heat
and all other components test
good replace the magnetron and
retest.