7-15
- CAUTIONS -
- DISCONNECT THE POWER SUPPLY CORD
FROM THE WALL OUTLET WHENEVER
REMOVINGING THE CABINET FROM THE UNIT.
PROCEED WITH THE TESTS ONLY AFTER
DISCHARGING THE HIGH VOLTAGE CAPACITOR
AND REMOVING THE WIRE LEADS FROM THE
PRIMARY WINDING OF THE HIGH VOLTAGE
TRANSFORMER. (SEE FIGURE 23)
- ALL OPERATIONAL CHECKS WITH MICROWAVE
ENERGY MUST BE DONE WITH A LOAD (1 LITER
OF WATER IN CONTAINER) IN THE OVEN.
A. TEST PROCEDURES
COMPONENTS
TEST PROCEDURES
RESULTS
MAGNETRON
(Wire leads are
removed)
HIGH-VOLTAGE
TRANSFORMER
(Wire leads are
removed)
1) Measure the resistance: Across the
filament terminals of the magnetron with
an ohm-meter on Rx1 scale.
2) Measure the resistance: Between each
filament terminal of the magnetron and
the chassis ground with an ohm-mater
on high test scale.
1) Measure the resistance:
With an ohm-meter on Rx1 scale.
a. Primary winding;
b. Filament winding;
c. Secondary winding;
2) Measure the resistance:
With an ohm-meter on highest scale.
a. Primary winding to ground;
b. Filament winding to ground;
Normal reading:
Less than 1 ohm.
Normal reading:
Infinite ohms.
NOTE: Replace the magnetron, if the
magnetron checks and all of the high
voltage component tests are good, but
the unit still does not heat a load.
Normal readings:
Approx. 0.3 to 0.5 ohm.
Less than 0.1 ohm.
Approx. 65 to 120 ohms.
Normal readings:
Infinite ohms.
Infinite ohms.
NOTE: A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS
SERVICED FOR ANY REASON.
Figure 23
Primary
Winding
Secondary
Winding
Filament
Winding
TEST AND CHECKOUT PROCEDURES, AND TROUBLE SHOOTING
Summary of Contents for NN-S251WL
Page 9: ...5 1 SCHEMATIC DIAGRAM OVERALL CIRCUIT DIAGRAM ...
Page 10: ...MATRIX CIRCUIT FOR TOUCH KEY BOARD 5 2 ...
Page 36: ...8 1 SCHEMATIC DIAGRAM OF P C B ...
Page 37: ...8 2 PRINTED CIRCUIT BOARD ...
Page 38: ...3 2 1 EXPLODED VIEW DOOR PARTS MODEL NN S251 4 1 9 7 65 6 5 8 ...
Page 39: ... 2 ESCUTCHEON BASE ASSEMBLY 12 10 13 14 11 67 60 66 ...
Page 40: ... 3 OVEN CAVITY PARTS 26 64 63 65 66 18 16 21 23 24 25 66 66 19 17 15 20 64 22 22 27 ...
Page 41: ... 4 DOOR HOOK PARTS 31 28 32 69 30 29 61 ...
Page 42: ... 5 INTERIOR PARTS I 65 42 33 35 36 37 62 63 34 39 41 38 60 43 63 60 40 63 44 60 60 60 ...
Page 43: ... 6 INTERIOR PARTS II 45 53 46 48 49 51 65 65 60 55 50 47 54 52 ...