Chapter 4 Electrical Installation 25
Liebert.CRV+ Series Air Cooled Precision Air Conditioner User Manual
4.2.3 Connecting Control Cable
The location of terminal block for cable connection in site is shown in Figure 4-1. The amplified view of the terminals
is shown in Figure 4-3.
76
75
71 62
70 61
38 GND
37 12V
24 B2
51 A2
64
63
TB3
Connecting
control cables
Description of terminals & port:
TB3: Rack sensor
75, 76: Common alarm
63, 64: Solenoid valve of liquid route
70, 71: Control cable of outdoor unit
61, 62: CAN communication
37, 38: Remote on/off
24, 51: Water-under-floor sensor
B2, A2, GND, 12V: SIC card
Figure 4-3 Terminal block for cable connection in site
Note
The connection personnel must take anti-static measures before connecting the control cables.
Water-under-floor sensor
If a water-under-floor sensor is equipped, you should connect one end of the sensor to terminal 51#, and the other
end to the common terminal 24#.
Each unit can be connected with any number of sensors in parallel, but only has one water-under-floor alarm.
SIC card
If an SIC card is equipped, you should connect A#, B#, GND#, 12# on the SIC card to the counterparts on the
terminal block respectively. Refer to
Appendix 1 Circuit Diagram
for details.
Rack sensor
Each unit can be connected with ten temperature sensors at most. It is recommended that the sensors be located in
front of the heat loads to achieve the most precise temperature. If the sensors are connected in series (see Figure
4-4), each temperature sensor monitors the temperature of air entering each rack, and the read temperature value is
used to control unit operation. The standard location of the sensor is 1.5m height. Therefore, the sensors should be
placed on positions shown in Figure 4-4, or the devices cannot operate normally.
1.5m
1.5m
1.5m
传感器
传感器
Sensor
1.5m
1.5m
Figure 4-4 Layout figure of rack sensors
