Power Relay Control; Protection From Total Current Control - LG LS-J0761NL Service Manual

13. Power relay control

• Power relay turns on 1 second later after the power is input to the outdoor unit.
• Control sequence : power on

14. Protection from total current control

I CT1 control
• If the operating current reaches I1, the operating frequency of the compressor decrease.
• After decreasing the operating frequency by 1step, if operating current is below I1 for 24 seconds continuous-
ly, the operating frequency of compressor increase by 1step.
I CT2 control
• If the operating current of the appliance reaches I2, the compressor stop instantly and 2 minutes later the
compressor restart again.
• If CT2 occurs twice within 1hour, the appliance turn off and display ERROR CODE 7.
Control table
Model
Condition
Operating mode
below 38°C
(outdoor temp.)
over 38°C
(outdoor temp.)
cf. I1 is set the lowest level between intial value and in case dectection of dc paeak current.
15. Protection from DC Peak Current
I DC Peak Current Error by a fault signal of IPM
• If the operating current of IPM reaches 35A ±3A, the compressor stop instantly.
• If DC PEAK occurs 3 times within 1 hour, the appliance turns off and display ERROR CODE 6.
I DC Peak Current Error by the compressor lock
• If the DC LINK voltage below DC 350V occurs 5 times within 1 hour while the compressor is operating, the
appliance turns off and display ERROR CODE 6.
I DC Peak Current Error by the Outdoor Fan Lock
• If it's 5 times within 1 hour in case of the temperature of outdoor pipe TH is over 65°C while the compressor is
operating, the appliance turns off and display ERROR CODE 6.
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
➔ ➔
PTC operating
7K Btu Series
Cooling Heating
I1
8.5A 10A
I2
11.5A
I1
8A 9.5A
I2
11.5A
power relay on
❇ I1:Current of operating frequency down
I2: Current of compressor cut off
9K Btu Series 12K Btu Series
Cooling Heating Cooling Heating
9A 10.5A 10.5A
13.5A
8.5A 10A 10A
13.5A
- 24 -
18K Btu Series
Cooling Heating
12A 12.5A
13.5A 16A
11.5A 12A 13.5A
13.5A 16A
LGE Internal Use Only
14A