Sharp R-1850, Руководство по обслуживанию

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18
R-1850
R-1851
32Ω
20Ω 45Ω
HOOD
FAN
CAPACITOR
YLW
RED
BLU
BLK
1
2
3
WHT
4
5 1 2 3
4 5
BLU BLK WHT
YLW RED
6-PIN CONNECTOR
OF HOOD FAN MOTOR
Ω Ω
Ω
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
If the monitor fuse in the secondary-monitor switch and primary interlock relay circuit is blown when the
door is opened, check the primary interlock relay, door sensing switch, secondary interlock switch and
monitor switch according to the "TEST PROCEDURE" for those switches before replacing the blown
monitor fuse.
CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE, TEST THE PRIMARY INTERLOCK
RELAY, SECONDARY INTERLOCK SWITCH, DOOR SENSING SWITCH AND MONITOR
SWITCH FOR PROPER OPERATION.
If the monitor fuse is blown by improper switch operation, the monitor fuse and switch must be replaced
with "monitor fuse and switch assembly" part number FFS-BA016/KIT, even if the monitor switch
operates normally. The monitor fuse and switch assembly is packed with 20 ampere fuse and switch.
I BLOWN MONITOR FUSE
MAGNETRON TEMPERATURE FUSE
A continuity check across the temperature fuse terminals should indicate a closed circuit unless the
temperature of the temperature fuse reaches approximately 302˚F(150˚C). If the temperature fuse has
opened, replace the temperature fuse.
An open temperature fuse indicates overheating of the magnetron assembly. Check for restricted air flow
to the magnetron through the opening in the chassis, especially the cooling fan and cooling duct.
CAUTION: IF THE TEMPERATURE FUSE INDICATES AN OPEN CIRCUIT AT ROOM TEMPERA-
TURE, REPLACE THE TEMPERATURE FUSE.
J TEMPERATURE FUSE TEST
A continuity check across the thermal cut-out terminals should indicate an open circuit unless the
temperature of the thermal cut-out reaches approximately 140˚F(60˚C) or more. At that temperature,
the contacts will close. The thermal cut-out opens automatically at approximately 113˚F(45˚C).
K HOOD THERMAL CUT-OUT TEST
Disconnect connector-E from the control unit. Measure the resistance of the thermistor with an
ohmmeter. Connect the ohmmeter leads to Pin No’s E-3 and E-4.
Room Temperature Resistance
68˚F(20˚C) - 86˚F(30˚C) Approx. 360 k
Ω
- 152 k
Ω
If the meter does not indicate above resistance, replace the thermistor
L THERMISTOR TEST
If the motor does not turn, touch the HOOD FAN button once (set hood fan motor power "HIGH") and
check voltage between pins "1" and "2" (Blue and Black wires) of the 6 pin connector. If 120 Volts appear
and the hood capacitor is good, replace the hood fan assembly. If 120 Volts does not appear, check the
motor circuit. The resistance values of motor terminals are as follows:
M HOOD FAN MOTOR TEST
Resistance between;
BLU (1) AND YLW (4) = 0
Ω
(Shorted)
BLK (2) AND YLW (4) = 32
Ω
BLU (1) AND BLK (2) = 32
Ω
BLK (2) AND WHT (3) = 20
Ω
WHT (3) AND RED (5) = 45
Ω