ACP DEC18M, Service Manual

Page: 21 / 31

Illustration Component Testing Results
Thermal Cutout
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
50K
Ω 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 M
Ω. If no deflection occurs, or
if continuous deflection occurs,
replace capacitor.
Terminal to Case: Infinite
resistance.
ALWAYS USE CORRECT
SIZE