7. TEST PROCEDURES AND TROUBLESHOOTING
CAUTION - DISCONNECT THE POWER SUPPLY CORD FROM THE WALL OUTLET WHENEVER REMOVING THE CABINET FROM THE UNIT. PROCEED WITH THE TESTS ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE LEAD WIRES FROM THE PRIMARY WINDING OF THE HIGH VOLTAGE TRANSFORMER. ( See Figure 3 )
Filament Windings
Secondary Winding
Primary Windings
Figure 4
A. TEST PROCEDURE
COMPONENT CHECKOUT PROCEDURE 1) Check for resistance : Across the filament terminals of the the magnetron with an ohmmeter on Rx1 scale. RESULTS Normal reading : Less than 1 ohm.
Figure 5 2) Check for resistance : Across the filament terminals of the magnetron and the chassis ground with an ohm-meter on highest scale. Normal reading : Infinite ohms
MAGNETRON
Figure 6
The chart below shows the firing times of the variable power relay for the EM-G4750 model. The table should be used as a means to check the magnetron is operating correctly and producing any other power setting apart from full power.
Power Level High (900W) M-High(750W) Roast (450W) Simmer(300W) Warm (150W) Low (80W)
On Time/s % On Time (inc.�ramp up� time) 30.0 100 28.0 93 18.0 60 13.0 43 8.0 27 6.0 20
