10.3.1 Vertiv™ Liebert® EconoPhase Control
Liebert® EconoPhase operation has three main controlled parameters:
• Room temperature
• Refrigerant temperature
• Pump pressure differential (outlet pressure - inlet pressure)
Room Temperature
When the system is in Pump Mode, the room temperature is controlled by modulating the pump speed with a variable
frequency drive. The load requirement will determine if one pump or two are needed. Figure 10.4 below, shows the sequence
of operation in terms of pump speed. Minimum speed is 45% and maximum speed is 100%. See Table 10.1 on the next page,
for more detail on the events depicted and the conditions that trigger action.
Figure 10.4 Two Circuit Pump Control
Event Condition to Trigger Action Action
B to A
Pump 2 Off; and Pump 1 at minimum speed for 60 sec.;
and
Delta T [indoor air temperature - setpoint] <-4°F (2.2°C)
Pump 1 turns Off.
Pump 2 remains Off.
A to B
Both Pump 1 and Pump 2 Off
and
DeltaT>0°F (0°C)
Pump 1 turns On and runs on PID.
Pump 2 remains Off.
F to G
Pump 2 Off and Pump 1 at maximum speed for 600
seconds
and
Delta T >1°F (-0.6°C)
Pump 2 turns On at starting speed, then goes to minimum speed
immediately.
Pump 1 continues to run on PID.
Table 10.1 Events and Actions of 2 Circuit Pump Control
10 Control Operation Proprietary and Confidential ©2024 Vertiv Group Corp. 37
Vertiv™ Liebert® MCV Installer/User Guide
To Next Page
Loading...
