Control Setup - "Cooling Control Setup" Screen - Frick QUANTUM ACUair Operation Instructions Manual

Cooling Control Setpoints
temperature in either Process or Cleanup Mode. A PID
loop is the control structure used to move the temperature
toward setpoint. The Cooling Proportional Band, Dead
Band and Integration Time Setpoints adjust the speed and
precision of this PID control. The Process Cooling CV Max
and Min Setpoints set the range for the PID loop.
In Process Mode, the unit will maintain the Process
Control Setpoint. While the Outside Air Temperature is
greater than Process Cooling Lockout, the unit attempts to
hold the Return Air Temperature at the Process Control
Setpoint. If the Return Air Temperature drops below the
Process Control Setpoint, the PID output is set to the
Process Cooling CV Min Setpoint. The PID output remains
at the Process Cooling CV Min Setpoint until the Return
Air Temperature rises above the Process Control Setpoint
plus the Differential Setpoint.
Temperature drops below the Process Cooling Lockout,
cooling is temporarily disabled, as it is not needed.
In Cleanup Mode, as cooling is required, the unit will
maintain the Cleanup Cooling Temperature Setpoint.
While the Outside Air Temperature is greater than the
Cleanup Cooling Lockout, the unit attempts to hold the
Discharge Air Temperature at the Cleanup Cooling
Temperature Setpoint. If the Discharge Air Temperature
drops below the Cleanup Cooling Temperature Setpoint,
the PID output is set to the Process Cooling CV Min
Setpoint. The PID output remains at the Process Cooling
CV Min Setpoint until the Discharge Air Temperature rises
above the Cleanup Cooling Temperature Setpoint plus the
Cooling Differential Setpoint.
Temperature drops below the Cleanup Cooling Lockout,
cooling is temporarily disabled, as it is not needed.
The Demand Setpoint determines the PID output that will
bring on either Stage #1 or Stage #2. The Min On Time
FRICK QUANTUM CONTROL PANEL
ACUair OPERATION
CONTROL SETUP -
"COOLING CONTROL SETUP" SCREEN
are used to maintain
If the Outside Air
If the Outside Air
Setpoint forces the unit to remain on for a minimum time
while the Min Off Time Setpoint forces the unit to remain
off for a minimum time.
Together they keep the unit from rapidly cycling on and
off. When the unit has two stages of cooling, the
Interstage Delay Setpoint holds Stage #2 off for a
minimum amount of time after Stage #1 has turned on.
Below is an example of cooling in Process Mode:
3
Setpoints -
Process Control Setpoint = 35 °F
Process Cooling Lockout = 30 °F
Differential = 3 °F
Proportional Band = 4 °F
Dead Band = 0 °F
Integration Time = 0 Sec.
Process Cooling CV Max = 95%
Process Cooling CV Min = 5%
Stage #1 Demand Setpoint = 25%
Stage #2 Demand Setpoint = 50%
Min On Time = 30 Sec.
Min Off Time = 30 Sec.
Interstage Delay = 20 Sec.
The Cooling PID output, also called the Demand value,
determines the amount of cooling required and regulates
the amount of cooling applied to the room. As long as the
Outside Air Temperature remains below 30 °F (Process
Cooling Lockout), cooling is disabled and the Cooling PID
output remains at 0%. When the Outside Air Temperature
rises above 30 °F, the Cooling PID output is calculated
based on the Return Air Temperature and the Process
Control Setpoint.
When the Cooling Dead Band and Integration Time are
set to 0, the PID calculation reduces to a simple
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