APC ACRP500 User Manual

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InRow RC/RD/RP (600 mm) User’s Guide
Setpoints 
Assign the following group setpoints and then click Apply. The setpoints for each mode must be within 
the following ranges:
•  Cool: 64.4–77.0°F (18.0–25.0°C)
•  Supply Air: 62.6–73.4°F (17.0–23.0°C)
The following setpoints apply to the ACRP100 and ACRP500 cooling units:
•  Dehumidify: 35.0–60.0% RH 
•  Dehumid Deadband: 2.0–10.0% 
•  Humidify: 25.0–50.0% RH 
•  Reheat: 50.0–64.4°F (10.0–18.0°C)
For ACRP100 and ACRP500 cooling units: The Supply Air setpoint must be at least 2.0°F (1.1°C) 
above the Reheat setpoint. The Dehumidify setpoint must be at least 5% above the Humidify setpoint. 
If the Supply Air setpoint is greater than the Cool setpoint, the cooling unit activates an alarm and resets 
the Supply Air setpoint to equal the Cool setpoint. 
Configuration
Number of units in group. 
Enter the number of units in the group, then click Apply. Up to twelve 
units can be configured to work as a group.
Configuration type. 
Select the configuration type, which is the air flow control strategy the group uses, 
then click Apply:
•  RACS—Rack Air Containment System. Air flow in the enclosure is controlled by a ducting 
system fitted to the enclosure.
•  HACS—Hot Aisle Containment System. Air flow in the room is controlled by enclosing the hot 
air aisle.
•  In-Row—Air flow is horizontal, to allow in-row operation of the cooling group.
Percent glycol. 
Enter the percentage of glycol the group uses to cool the environment. This 
information is used to calculate the amount of energy (in kW) required by the unit. Percent glycol 
applies only to ACRC500 and ACRP500 cooling units. Only a qualified service technician should 
change the amount of glycol in the group.
PID control settings. 
For ACRP100 and ACRP500 cooling units. The Proportional + Integral + 
Derivative (PID) control loop is used to control the output of the group. Enter the settings for the Cool 
and Reheat PIDs, and the Humidify Sensitivity Band, then click Apply.
Note: The loops must be tuned after the room load is in place, and then periodically if the 
room load changes. Only a qualified service technician should perform PID tuning.
For more information about PID tuning, see the Operation and Maintenance manual for 
your cooling unit, available on the Utility CD or on the APC Web site, www.apc.com.