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Liebert CRV
Liebert CRV - PD - 265086 - 11.01.2018
3.1 Standard features
Air cooled models
DX COOLING COIL
It is constructed of copper tubes and hydrophilic coated aluminium fins. The hy
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drophilic coating provides superior water carryover resistance. A stainless steel condensate drain pans
are provided.
REFRIGERATION SYSTEM
Single refrigeration circuit includes a liquid line filter drier, a refrigerant
sight glass with moisture indicator, an electronic expansion valve, and a liquid line solenoid valve.
COMPRESSOR
The compressor is an R410A DC inverter scroll type with variable capacity operation
from 30-100%. The limit of capacity variation is depending by the installation type and the room condi-
tions. The compressor has a suction gas cooled motor, vibration isolators, internal thermal overloads,
manual reset high pressure switch, low pressure and high pressure transducer, crankcase heater, in-
ternal centrifugal oil pump, and an operating speed of 3000RPM @ 50Hz.
ELECTRONIC EXPANSION VALVE DEVICE (EXV)
The valve is designed for modulating control of
refrigerant circuits with high speed and high precision. It is suitable for use as expansion device in
refrigerant circuits with DC Inverter Scroll compressor, with organic safety refrigerants (i.e. R410A).
For variable capacity systems, an EXV provides superior performance as compared to a traditional
thermostatic expansion valve (TXV), due to:
•
Precise flow control
•
Positioning time
Electronic expansion valve ensure a better control on superheating at the outlet of the evaporator, en-
suring at same that compressor will never be filled by liquid. Moreover the EXV valve let the condensing
temperature goes down to 33°C.
FAN
The unit is equipped with five (CR021) or three (CR011) direct driven radial fans with backward
curved blades and Electronically Commutated DC motors; commonly referred to as EC plug fans.
The fan speed is variable and automatically regulated by the iCOM control through all modes of oper-
ation. Each fan has a dedicated motor which provides a level of redundancy. The fans pull air through
the coil and are located on the front side of the unit.
iCOM CONTROL SYSTEM
The Liebert CRV is controlled by the iCOM Control System. The standard
user interface is the Large Graphical Display (320x240 pixels, backlit) which presents system informa
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tion and allows all parameters to be viewed and adjusted. It features push-button navigation, operation-
al status LEDs, and a 3-level password protection system. iCOM without display is available as option.
Unit without display can be controlled through a display of another unit in the same group or through a
service display. Unit-to-Unit communication with other Liebert CRVs and two IntelliSlot communication
card housings are included as standard.
2T RACK TEMPERATURE SENSORS
Consist of a vented case with two temperature probes. Up
to 10 2T housings (20 temperature probes) can be connected to a Liebert CRV. One 2T housing and
both sensor probes are to be attached to a rack the cooling unit is conditioning. The sensors provide
real-time, direct feedback to the cooling unit to optimize the amount of cooling and airflow required; in
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creasing energy efficiency and ensuring proper rack inlet air temperatures. The sensor data can also be
reported to remote BMS and monitoring systems. The sensor network consists of one CAN wire leaving
the cooling unit and connecting to a 2T sensor. Each remaining 2T sensor is connected to the previous
sensor; often referred to as a daisy-chain configuration.
REMOTE SHUTDOWN TERMINAL
Provides the customer with a location to remotely shut down the
unit.
COMMON ALARM CONTACT
Provides the customer with a set of normally open (n/o) contacts for
remote indication of unit alarms.
CABINET
The exterior steel panels are custom powder coated to protect against corrosion. The dou-
ble wall constructed side panels separate the ½”, 2.0 lb/ft3 insulation from the airstream. The unit is
mounted on casters for quick installation and provided with levelling feet. The perforated inlet and outlet
panels have 81% open area.
SERVICE ACCESS
All service and maintenance is performed through the front and rear of the unit;
including any component removal. No side access is required. All electrical and piping connections are
made through the top and/or bottom of the unit.
FILTER
The unit is equipped with two air filters rated G2 following EN779, located within the cabinet,
and accessible from the rear of the unit. Air filter F5 are available as option. A filter clog alarm is included
as an option.
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