Sharp R-9X55 User Manual

TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
C
HIGH VOLTAGE RECTIFIER ASSEMBLY TEST
HIGH VOLTAGE RECTIFIER TEST
CARRY OUT 30 CHECKS.
Isolate the high voltage rectifier assembly from the HV circuit. The high voltage rectifier can be tes:ed
using an ohmmeter set to its highest range. Connect the ohmmeter across the terminai 3+C of it-,e h1gi7
voltage rectifier and note the reading obtained. Reverse the meter ieads and note this second reading.
The normal resistance is intinte in one direction and mor than 100 kiE in the other directlcn.
CARRY OUT 4R CHECKS
J
ASYMMETRIC RECTIFIER TEST
ASYMMETRIC
RECTIFIER
CARRY OUT 3D CHECKS.
C/ HfGH
VOLTAGE ?ECTiF!E?
Isolate the high voltage rectifier assembly from the HV circuit. The asymmetx :ez:ifier :a;: ze :t?s:~z
using an ohmmeter set to its highest range. Connect the ohmmeter across ;he term&s .A-5 ,;: :P
asymmetric rectifier and note the reading obtained. Reverse the meter ieads ana noye tr,!s :,~~-~o
reading. If an open circuit is indicated in both directions then the asymmetrx ect~fier s s!xr;
: 3f-x
asymmetric rectifier is shorted in either direction. then the the asymmetnc rest+er ‘s gret!zzc!, fa::/:i.:
and must be replaced with the high voltage rectifier. When the asymmetric rx:!f&r 1s Jeiec:ive ci;e,:-
whether magnetron. high voltage rectifier, high voltage wire or filament windirs ;+ ttx B!JW~~ ;cax~~-
former is shorted.
CARRY OUT 4R CHECKS
NOTE: For measurement of the resistance of the rectifier, the batteries of the rrieastiring +str~m~nt
must have a volyage at least 6 volts, because otherwise an infinite resistance migh; ze snown
in both directions.
.
D
HIGH VOLTAGE CAPACITOR TEST
CARRY OUT 3D CHECKS.
A.
B.
C.
D.
E.
F.
G.
Isolate the high voltage capacitor from the circuit.
Continuity check must be carried out with measuring instrument which is set to the highest resis-
tance range.
A normal capacitor shows continuity for a short time (kick) and then a resistance of about 10 MR
after it has been charged.
A short-circuited capacitor shows continuity all the time.
An open capacitor constantly shows a resistance of about IO MQ because of its internal 10 MQ
resistance.
When the internal wire is opened in the high voltage capacitor, the capacitor shows an infinite
resistance.
The resistance across all the terminals and the chassis must be inifinte when the capacitor is nor-
mal.
If incorrect readings are obtained, the high voltage capacitor must be replaced.
CARRY OUT 4R CHECKS
17

Sharp R-9X55 Specifications

General

Brand	Sharp
Model	R-9X55
Category	Microwave Oven
Language	English