Emerson Liebert CRV 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 C R 0 2 0 R A 1 C 7 S D 1 8 1 1 E L 1 0 P A User Manual

Page 77

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Liebert iCOM

®

Control

69

Liebert

®

CRV

Figure 57 Setpoints parameters screen - Page 1

Temperature Setpoint—This parameter selects a temperature that the cooling unit will maintain

by applying cooling and or reheats. This parameter is adjustable from 41-104°F (5-40°C), the factory

default setting is 73°F (22.7°C).
Temperature Control Sensor—This sensor controls the cooling capacity of the Liebert CRV. If the

unit is chilled water model, then this sensor controls the chilled water valve opening. If the unit is a

DX (direct expansion) model then this sensor will control the amount of digital scroll capacity.
Temperature Control Type—This parameter selects the type of control the system will use to

activate cooling, heating, humidification and dehumidification. A detailed description of each control

type can be found in 3.7 - Supply Control.
Temperature Deadband—This parameter can be set to avoid overshooting of the setpoint and

cycling between the reheats and cooling. The value entered into this field will be split in half by the

temperature setpoint. Example—If the temperature setpoint is 70°F (21.1°C) and a 4°F (2.2°C)

deadband is set, then no cooling will be activated until 72°F (22.2°C) and no heating will be activated

until 68°F (20°C) is reached.
Cooling Proportional Band—This parameter adjusts the activation points of compressors or rate

of change based on the actual sensor values deviation from setpoint. The smaller this number the

faster the compressors and valve(s) will increase capacity. Too small of a number may cause the unit

to short cycle the compressors or excessively reposition the valve.
Cooling Integration/Derivative—Cooling integration takes into consideration the amount of time

the actual temperature has deviated from the setpoint. The longer this deviation exists the more

corrective action the unit will use to achieve the setpoint. The derivative term monitors the rate of

change and will reduce or increase the amount of corrective action based on the actual temperature

increasing or decreasing toward the temperature setpoint.

S101
S102
S103
S104
S105
S106
S107
S108
S109
S110
S111

PASSWORD (Actual Level 0)

????

Temperature Setpoint

68 °F

Temperature Control Sensor

Remote Sensor

Temperature Control Type

Proportional

Temperature Deadband

2°F

Cooling Proportional Band

9°F

Cooling Integration /Derivative min /

sec

Heating Proportional Band

9°F

Heating Integration /Derivative min /

sec

CRV Control

Average

SETPOINTS (page 1 of 4)

UNIT 01

to change parameter

for next/previous unit

to select parameter

to confirm

then

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