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Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
Control logic
9.1 Function
: Power module failure protection by checking the temperature of heat sink.
There is a temperature sensor for checking the heat sink temperature.
9.2 Heat sink sensor failure error
Short Check : if temperature
≥
130˚C
Open Check : if temperature < - 30˚C
System will go in self diagnosis (error 65) is displayed and product stops.
9.3 Heat sink temperature control
a)Heat sink temperature < T1 : No limitation on compressor frequency
b)Heat sink temperature < T2 : Compressor frequency fixed
c)T2
≤
heat sink temperature < Toff : Compressor frequency down by
a
Hz in a minute
d) Heat sink temperature
≥
Toff : Compressor will be off.
System will stop if this situation occurs 5 times in 1 hour and error code will be generated also self diagnosis will start.
If high temperature situation occurs 5 times in 1 hr system counts 1 error and after that 4 times if this situation occurs
system stops and give error code.
If the temperature reached Toff condition system will count 5 times after that and system will stop with error code.
9. Heat sink control
COMP Hz
Toff
°
C
T2
°
C
Hz
Down
OFF
Set
frequency
Hz
Down
T1
°
C
OFF
Heat Sink temp
Set
frequency
Frequency
fixed
Frequency
fixed
