LG FM15AH UL3, Svc Manual

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Only for training and service purposes
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Part 3 Control logic
11.1 Function
: Power module failure protection by checking the temperature of heat sink.
There is a temperature sensor for checking the heat sink temperature.
11.2 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.
11.3 Heat sink temperature control
a) Heat sink temperature < T2 : No limitation on compressor frequency
b) T2
≤
heat sink temperature < Toff : Compressor frequency down by 5 Hz
c) 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.
11. Heat sink control
Heat Sink temp
COMP Hz
Set
frequency
5 Hz
(Option)
Down
Set
frequency
5 Hz
(Option)
Down
OFF
Set
frequency
Toff=85(Option)˚C
T2=75 (Option)˚C
T1=70 (Option)˚C