Step(Frequency) Control - LG FM15AH UL3 Svc Manual

Part 3 Control logic

2. Step(frequency) control

2.1 Frequency control
Frequency that corresponds to each rooms capacity will be determined according to the difference in the temperature of
each room and the temperature set by the remote controller.
There are various factors determining the frequency.
1. Indoor unit capacity value.
2. Temperature compensation factor
3. Initial frequency setting
Indoor temperature
Indoor capacity
Indoor On/OFF
Selected fan speed
Indoor
System
data
ON/Setting
2.2 Primary step setting
: Capacity steps of compressor are decided by ∑Qj (Summation of capacity code), TA0(Outdoor temp.), TAI(Indoor
temp.), DTAI (Step Compensation of temperature difference Indoor Temp. and Setting Temp.
Comp Step = (Step base+Long piping compensation) x ∆Step TAO x ∆Step TAI x ∆Step DTAI
Step base
Long piping
∆Step TAO
∆Step TAI
∆Step DTAI
✽ Target frequency step (Step base) exceeds maximum step, the Step base value follows the maximum step value.
✽ The compressor get the minimum step in case Step base value is lower than the minimum step of operating
capacity.
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Basic formula of
Outdoor
calculation
Temperature
Compressor setting
Outdoor Calculation of
data set frequency
Standard frequency step by ∑Qj (Summation of capacity code)
Comp. Step compensation by setting long piping
step compensation by TAO (Outdoor temp.)
step compensation by TAI (Indoor temp.)
Step Compensation of temperature difference Indoor Temp. and Setting Temp.
- 42 -
To & fro
feedback
Start
system
System
error
Continues
Stop
check system
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