Canbus Failure; Liebert Dse With Optional Liebert Econophase; Electronic Expansion Valve (Eev); Figure 40 Canbus Connections - Emerson Liebert iCOM Manual

Figure 40 CANbus connections

Factory-Installed CANbus Cable
Field-Installed CANbus Cable
Indoor Unit With
Liebert iCOM
3.8.1

CANbus Failure

The Liebert iCOM will keep the cooling system operating despite the loss of CANbus communication
between the Liebert DSE, the Liebert EconoPhase and/or the condenser. The Liebert DSE will
operate in DX mode, using its own sensors to maintain room conditions. The Liebert MC will operate
as a stand-alone unit, maintaining refrigerant pressure and temperature based on its own sensors.
The Liebert EconoPhase will remain idle with all diverting valves in DX mode.
3.8.2

Liebert DSE with Optional Liebert EconoPhase

The Liebert DSE can be equipped with an optional pumped refrigerant Liebert EconoPhase to reduce
power used for cooling when the outside air is cool enough. All components that help to drive its
efficiency are automatically controlled with the Liebert iCOM and do not need to be adjusted in the field.
3.8.3

Electronic Expansion Valve (EEV)

The Liebert DSE controls superheat with an electronic expansion valve (EEV). The EEV controller
adjusts the orifice based on suction pressure and temperature. The EEV control will drive the valve to
maintain the superheat setpoint, set in the Liebert iCOM, using a Proportional, Integral, Derivative
(PID) routine. The PID control values are set at the factory for most applications. These default PID
values will allow stable superheat control of the unit.
For DA080/085, the default PID values must be updated to special PID values when the condenser is
installed at the same level as the evaporator, plus or minus 10 feet (3m). The PID control values (both
default and special) are noted Table 10.
Table 10 EEV control values, default and special settings
Model #
DA080/085
DA125/150
® ®
Liebert iCOM for Liebert DSE
TB49
EEV Settings
Default Values
E144 = MAN
E160 = 0.7
E161 = 250
E162 = 4.2
E144 = MAN
E160 = 1.8
E161 = 250
E162 = 2.5
™
Liebert
TB50
EconoPhase
Circuit 1
TB49
TB50 Liebert
EconoPhase
Circuit 2
TB50
TB49
EconoPhase
CANbus Terminal Block
TB49
TB50 Liebert
MC Unit
Circuit 2
TB49
TB50 Liebert
MC Unit
Circuit 1
TB49
Special Values
(condenser and evaporator
at same level ±10' [3m])
E144 = MAN
E160 = 1.5
E161 = 250
E162 = 2.5
50
On
1
J6
3 1 2 3 4 5 6 7 8
CAN
On
1
J6
3
1 2 3 4 5 6 7 8
CAN
Liebert
On
1
J6
3
1 2 3 4 5 6 7 8
CAN
On
1
J6
3
1 2 3 4 5 6 7 8
CAN
Operation