- 30 -
Copyright ©2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
Control logic
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
2.2 Primary step setting
: Capacity steps of compressor are decided by
∑
Qj (Summation of capacity code), TA0(Outdoor temp.), TW(Inlet Water
temp.),DTW(Difference Outlet Water temp. and Setting Outlet Water temp.), DTR(Difference Air Indoor temp. and
Setting Air temp.), OP_ind(a number of Operating Indoors).
Comp_Step=(St Long-piping) x
∆
Step_TAO x
∆
step_TW x
∆
st
∆
step_OP_ind ....(1)
Comp_Step=(StLong-piping) x
∆
Step_TAO x
∆
step_TW x
∆
st
∆
step_OP_ind.....(2)
✽
Between formular (1) and (2) only one formular is applied by system setting.
✽
If 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.
2. Step(frequency) control
System
ON/Setting
Indoor
data
Outdoor
data
Calculation of
set frequency
Start
system
Continues
check
To & fro
feedback
Indoor temperature
Indoor capacity
Indoor On/OFF
Outdoor
Temperature
Basic formula of
calculation
Compressor setting
Stop
system
System
error
Step_base
Standard frequency step by
∑
Qj (Summation of capacity code)
∆
Step_TAO
Step compensation by TAO (Outdoor temp.)
∆
Step_TW
Step compensation by TW (Water inlet temp.)
∆
Step_DTW
Step compensation of temperature difference Outlet Water temp. and Setting temp.
∆
Step_DTR
Step compensation of temperature difference Indoor Air temp. and Setting temp.
∆
Step_OP_ind
a number of Operating indoor units
Long-piping
Comp. Step compensation by setting long piping
