LG MC-3089NBC Service Manual page 20

COMPONENTS
FUSE
HEATER ELEMENT
(Wire leads removed.)
MAGNETRON
THERMOSTAT
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
TEST PROCEDURE
Check for continuity of the fuse with an
multi-meter.
NOTE: If the fuse is blown, check the primary, the secondary, and the monitor
switches, H.V.D. and H.V.C. before replacing the fuse.
If the fuse is blown by improper switch operation replace the defective switch
and the fuse at the same time. Replace just the fuse if the switches operate
normally.
Measure the resistance.
(Multi-meter scale: Rx1)
Measure the resistance with 500V-100M ohm
insulation resistance meter.
NOTE: Make sure heater is fully cooled when tested.
5-10
RESULTS
Normal Abnormal
Normal:
*Grill heater
Approx. 42 ohm
o
(at 20 ~ 30 C)
*Convection heater
Approx. 63 ohm
o
(at 20 ~ 30 C)
Normal: more than 0.5 Mohm
0°C~Approx.60°C Approx.60°C
0°C~Approx.145°C Approx.145°C
LGE Internal Use Only