Sharp R-4S1FH, Руководство по обслуживанию

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17
R-4S1FH
(7) If improper operation is indicated, the control unit is probably defective and should be checked.
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary
on the PWB, this foil pattern acts as a fuse.
1. Foil pattern check and repairs.
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Follow the troubleshooting guide given below for repair.
STEPS OCCURRENCE CAUSE OR CORRECTION
1 Only pattern at "a" is broken. *Insert jumper wire J1 and solder.
2 Pattern at "a" and "b" are broken. *Insert the coil RCILF2003YAZZ between "c" and "d".
5) Make a visual inspection of the varistor.
Check for burned damage and examine
the transformer with a tester for the
presence of layer short-circuit (check
the primary coil resistance which is
approximately 540 ohms ± 20%). If any
abnormal condition is detected, replace
the defective parts.
6) Reconnect all leads removed from components during testing.
7) Re-install the outer case (cabinet).
8) Reconnect the power supply cord after the outer case is installed.
9) Run the oven and check all functions.
2. Follow the troubleshooting guide given below, if indicator does not light up after above check and repairs
are finished.
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Disconnect the leads to the primary of the power transformer.
5) Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
6) After that procedure, re-connect the power supply cord.
7) Follow the troubleshooting guide given below for repair.
STEPS OCCURRENCE CAUSE OR CORRECTION
1 The rated AC voltage is not present between Check supply voltage and oven power cord.
the normal open terminal of the relay RY1 and
the normal open terminal of the relay RY2
2
The rated AC voltage is present at primary Low voltage transformer or secondary circuit defective.
side of low voltage transformer. Check and repair.
8) Disconnect the power supply cord, and then remove outer case.
9) Open the door and block it open.
10) Discharge high voltage capacitor.
11) Reconnect all leads removed from components during testing.
12) Re-install the outer case (cabinet).
13) Reconnect the power supply cord after the outer case is installed.
14) Run the oven and check all functions.
M FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
MR
7
MCR
M27A
94V-
R
T1
1
RY2
(J1)
a
b
c
d