16
User Setup – EEV Control
The electronic expansion valve meters the amount of
refrigerant in the precise quantity in order to
maintain liquid level.
Figure 39 - User Setup – EEV Control Setup
Table 5 – EEV Control Setup Parameters
Menu Item
Description
Default Value
Mode
Selection
In Auto Mode, the control system
adjusts the valve to maintain
liquid level. In manual mode, the
system drives the valve to a fixed
position and holds it there for
service diagnostic purposes.
AUTO
Kp Proportional
PID
value
0.015
Ti Integral
PID
value
100.000
Td Derivative
PID
value
0.000
Liquid Level
Setpoint %
Target Liquid Level Setpoint
percent
64.0
User Setup – Compressor Staging
Figure 40 - User Setup – Compressor Staging Setup
Table 6 – Compressor Staging Setup Parameters
Menu Item
Description
Default Value
Staging
Mode
In Auto Mode, the control system
adjusts the number of staged
compressors relative to the
demand and available
compressors. In manual mode, the
number of staged compressors
depends on the Manual Mode
Value relative to available
compressors.
AUTO
Pressure
Differential
Assistance
(PDA)
Pressure Differential Assistance
will energize all compressors
when the circuit first starts for the
time specified in the PDA Delay
parameter.
OFF
Kp Proportional
PID
value
1.000
Ti Integral
PID
value
100.000
Td Derivative
PID
value
0.000
Stage
Δ
T
If the process value rises above
the set point by this differential,
the first compressor will turn on.
1.0°F
Destage
Δ
T
If the process value drops below
the set point by this differential,
all compressors turn off.
5.0°F
Stage to
Stage Delay
This is the minimum delay
duration between stages on
multiple compressors. During this
time delay, the demand percent
calculation ceases to allow the
impact of the newly staged
compressor to influence the
system.
120 sec
