12-18
Samsung Electronics
12-3 PCB Inspection Method
12-3-1 Pre-inspection Notices
1. Check if you pulled out the AC power plug when you eliminate the PCB or front panel.
2. Don’t hold the PCB side not impose excessive force on it to eliminate the PCB.
3. Don’t pull the lead wire but hold the whole housing to connect or disconnect a connector to the PCB.
4. In case of outdoor PCB disassembly, check first the complete discharge of condenser (C103) after 30 seconds power off.
12-3-2 Inspection Procedure
1. Check connector connection and peeling of PCB or bronze coating pattern when you think the PCB is broken.
2. The PCB is composed of the 3 parts.
1.
●
Indoor Main PCB Part : MICOM and surrounding circuit, relay, room fan motor driving circuit and control circuit,
sensor driving circuit, power circuit of DC12V and DC5V, and buzzer driving circuit.
1.
●
Display part : LED lamp, Switch, Remocon module
1.
●
Outdoor Main PCB part : MICOM and surrounding circuit. IPM and PFC circuit and control circuit.
1.
●
EMI PCB Part : Line filter and Noise Capacitor, Varistor
12-3-3 Indoor Detailed Inspection Procedure
No
Procedure
Inspection Method
Cause
1
Plug out and pull the PCB
out of the electronic box.
Check the PCB fuse.
1) Is the fuse disconnected?
• Over current
• Indoor Fan Motor Short
• AC Part Pattern Short of the MAIN PCB
2
Supply power.
If the operating lamp
twinkles at this time,
the above 1)~3) have
no relation.
Checking the power voltage.
1) Is the DB71 input voltage AC200V~AC240V?
• Power Cord is fault, Fuse open. Wrong Power
Cable Wiring, AC Part is faulty.
2) Is the voltage between both terminals of the
C104 on the 2
nd
side of the transformer DC12V
±0.5V?
• Switching Trans or Power Circuit is faulty
3) Is the voltage between both terminals of OUT
and GND of IC19(KA7805) DC5V ±0.5V?
• Power Circuit is faulty, Load Short
25890A(1)_1.indd 18
2006-04-18 ｿﾀﾈﾄ 4:03:32
Summary of Contents for UH052EAV
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Page 115: ...14 10 Samsung Electronics MEMO ...
