Air PreciseAIR PCA Series, Инструкция по установке, эксплуатации и обслуживанию

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IOM-PreciseAIR
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3.8.2. Main Loop
Displays information about the system.
Time, date, U=PLC plan address.
Current room temperature and relative humidity
(RH).
Current setpoints for room temperature and
room relative humidity.
Unit status: ON or OFF. “OFF by INPUT” means
that the selector switch is in the OFF position.
“OFF by ALARM” means that there is an acti ve
alarm that requires the machine to turn off.
The system objective is to control the room
temperature and room RH by tracking these
values to match with the desired setpoints.
Values for room temperature and room relative
humidity from sensor mounted in the controlled
room environment, evaporator entering air
temperate from sensor mounted on the inlet of
the filter rack, and evaporator leaving
temperature from sensor mounted on the top of
the unit with the sensing element behind the
evaporator coil.
When demand is above 0%, compressors are
requested to start, load, and unload. The System
Demand assumes the highest value between
Cooling Demand and Humidity Demand. High
System Demand percentage values translates
into more compressors running.
Cooling Demand is calculated based on the
deviation between Room Temperature and its
setpoint.
Humidity Demand is calculated based on the
deviation between Room RH and its setpoint.
Displays suction (low pressure) and discharge
(high pressure) pressure values for each
compressor. These values vary with running
condition. Common values are:
Suction: 25-40 psi
Discharge: 130-170 psi