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PG2021 Global HAHU-VP-ECM-005
D . 3 .
C o n t r o l L o g i c s f o r I C o n t r o l
Control Logics for I Control For EC-S8 (300029=2)
2-pipe with modulating valve for EC-S8 (300046=0)
COOL MODE
1)
If Tr ≥ Ts +1 ºC, then cool operation is activated, MTV1 is turned on. Indoor fan runs at set speed.
DA2 is open at 10Vdc for 2 min. Then check Ti1,
MS300080=0,
When Ti1<=8ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting PID
calculation. The output is minimum output (Modbus300015 setting)-10VDc;
When 8<Ti1<=10ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 1 PID calculation. The output is minimum output (Modbus300015 setting)-10VDc;
When 10<Ti1<=12ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 2 PID calculation. The output is minimum output (Modbus300015 setting)-10VDc;
When 12<Ti1<=15ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
minus 3 PID calculation. The output is minimum output (Modbus300015 setting)-10VDc;
When 15<Ti1<=28ºC (Modbus 300017 setting), DA2 output is kept at 10Vdc;
When Ti1>28ºC(Modbus 300017 setting), DA2 output is at minimum (Modbus300016 setting); and report pre-heat alarm
MS300080=1,
DA2 output is based on cooling water flow reading and setting PID calculation. The output is minimum output
(Modbus300015 setting)-10VDc;
MS300080=2,
DA2 output is based on cooling pressure difference setting (MS300084) and 4-20mA input2 reading (MS400007) PID
calculation. The output is minimum output (Modbus300015 setting)-10VDc;
2) If Tr < Ts-1 ºC, then cool operation is terminated and MTV1 is turned off. DA2 is 0VDC. Indoor fan runs at set speed.
3) The range of Ts is 16 - 30 ºC or fixed according to Parameter 4 setting.
4) Indoor fan speed can be adjusted for low, medium, high and auto.
LOW TEMPERATURE PROTECTION OF INDOOR COIL
a)
If Ti1 ≤ 2 ºC for 2 minutes, then MTV1 is turned off; DA2=0VDC; If indoor fan is set for low speed, then it will run at
medium speed. If it is set at medium or high speed, then it will keep running at the same speed.
b)
If Ti1 ≥ 5ºC for 2 minutes, then MTV1is turned on. DA2 is calculated by delta T; Indoor fan runs at set speed.
FAN MODE
a)
Indoor fan runs at the set speed while heater, MTV1, MTV2 are turned off.
b)
Indoor fan speed can be adjusted to low, medium and high.
HEAT MODE
Heat mode without electrical heater (300047=0)
a)
If Tr ≤ Ts - 1 ºC, then heat operation is activated and MTV1 and MTV2 are turned on.
DA2 is open at 10Vdc for 2 min. Then check Ti1,
MS300080=0,
If Ti1<=28ºC (300017 setting), fan is turned on at low speed; DA2 is on at 10VDC;
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz
