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

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IOM-PreciseAIR
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When the unit is equipped with blowers VFD’s,
the system will decrease the blowers
demand/speed to control the temperature of
the air leaving the coil when in humidity control.
3.8.3. On/Off Unit
Unit address: 1 (cannot be changed)
Power By Display: ON. Set of OFF to turn unit off
by display. Regardless of the position of the
start/stop switch on the door the unit will not
start. Status will show “OFF by KEYPAD”
3.8.4. Setpoints
Allow an authorized user to change the setpoint
parameters.
Cooling is the setpoint for compressor demand
controls.
Room Heating and Leaving Heater setpoints are
used to control the heaters. Leaving Heater is
used for re-heat during humidity control.
When Humidity control is desired, change the
status to ENABLE. There are 2 components for
humidity control. The first one is the humidity
setpoint (shown here as 40.0%) and the
differential for when the humidity control should
start and stop.
Start humidity control: Humidity SP + Diff On
Stop humidity control: Humidity SP – Diff Off
In this case, Diff On is 3.0%, which sends the
equipment into humidity control when the
relative humidity (RH) reaches 43.0% and stops
the humidity control loop when RH is below
39.0% because Diff Off is 1.0%.
When the equipment enters humidity control, it
will increase System Demand and modulate the
blowers speed to achieve the Coil Out Temp
setpoint. In this case, the setpoint is 55.0%. The
Coil Out Temp setpoint shall be set in a manner
where the psychometrics properties of the air
leaving the unit are at desirable levels.
Set the compressors discharge pressure (HP)
setpoint. The water valve will modulate to
maintain this pressure (also known as
compressor head pressure).