Midea 22033210000002, Руководство по обслуживанию

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Service Manual , 2016-12
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10.Circuit description
10.1 Power Supply
AC input voltage is lowered by linear transformer, then filtered by rectifier diode & LC into DC 12V,
DV12V provide power to reply what controls the switches of compressor and defroster. DC12V is
changed through adjuster 7805 in to stable DC5V,DC5V provide the power to control chip, control chip
monitor the temperature changes in the refrigeratorIf no power detected in test, firstly check whether there
is input voltage between the L& N line of main PCB, if no input voltage(230V/115V), please check
whether there is power supply in the socket; if there is input voltage, put the black probe of multi meter
on the bottom of “GND” pin, and put the red probe on the bottom of “+5v” or “+12v” pins, if there is
“12v” or “5v” detected, check whether there is loose connection with these wiring connectors; if there is
no “12v” or “5v” detected, it means the main PCB is damaged, replace it by a new one.