Economizer Compressor Variable Geometry Diffuser Screen - York YK-EP Operation And Maintenance Manual

Economizer compressor Variable Geometry Diffuser screen

Figure 23: Economizer compressor VGD screen
This screen displays information pertinent to the Economizer VGD operation. Also, the Economizer
VGD can be manually controlled from this screen.
Table 56: Display only
Field/LED name
Stall Detector Voltage
High Limit
Low Limit
Mach Number
VGD Closed Limit Switch
VGD Opening (LED)
VGD Closing (LED)
Stall Count
Stall Time
YK-EP Style B Centrifugal Chiller
Description
Displays the Stall Detector output voltage as received by the
Microboard.
Displays the voltage, that if exceeded, will result in the VGD closing
to prevent a stall from occurring.
Displays the voltage, that if has dropped below the setpoint, will
cause the VGD to open, allowing more gas through the compressor.
Displays the speed of the refrigerant gas leaving the compressor in
percentage of Mach (the speed of sound).
Displays the status of the VGD Limit Switch. Displayed as CLOSED
when the switch is closed. This would be when the VGD is in the fully
closed position. Otherwise, displayed as OPEN.
Illuminates when a close signal is being applied to the VGD.
Illuminates when an open signal is being applied to the VGD.
Displays the number of times that the system had detected an
Economizer Compressor Stall.
Displays the accumulated time that the Stall Detector Board output
is greater than the High Limit Setpoint voltage while the chiller is
running.
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