Variable Geometry Diffuser Screen - York YK Style H Operation Manual

Variable Geometry Diffuser screen

Figure 41: Variable Geometry Diffuser screen
This screen displays information pertinent to the VGD operation. Also, the VGD can be manually
controlled from this screen.
Table 50: Display only fields
Field/LED name
Stall Detector Voltage
High Limit
Low Limit
Mach Number
VGD Closed Limit Switch
VGD Opening (LED)
VGD Closing (LED)
VGD Position
Maximum VGD Position
Surge Avoidance Surge Detected
(LED)
ACC Surge Detected (LED)
Stall Count
Model YK Style H Centrifugal Liquid Chillers with OptiView Control Center
Description
Displays the Stall Detector output voltage (x.xx VDC), as received by the Microboard.
Displays the High Stall Detector Voltage Limit. Set in the VGD Setpoints Screen with
Service Level Access.
Displays the Low Stall Detector Voltage Limit. Set in the VGD Setpoints Screen with
Service Level Access.
Displays the status of the VGD Limit Switch. Displayed as CLOSED when the VGD is in
the fully closed position. Otherwise, displayed as OPEN.
Displays the status of the VGD Limit Switch. Displayed as CLOSED when the VGD is in
the fully closed position. Otherwise, displayed as OPEN.
Illuminates when an open signal is being applied to the VGD.
Illuminates when a close signal is being applied to the VGD.
Shows the position of the VGD. 0 to 100% open.
Shows the maximum calculated value that the VGD will be allowed to open for the
present condition (0 to 100%). Opening too far could cause surge.
Illuminates momentarily when a surge is detected by the Surge Protection feature. If
equipped with a VSD or MV VSD, these are only the surges detected while the drive is
running at maximum frequency.
It illuminates momentarily when a surge is detected by the Surge Protection feature,
regardless of the VSD operating speed.
Only displayed if equipped with a VSD or MV VSD. Illuminates momentarily when a
surge is detected by the ACC function in the Microboard, while the drive is running at
less than maximum frequency.
Displays the number of times the Stall Detector Board output voltage goes above the
High Limit Setpoint. The count can be cleared with in ADMIN access level using the
VGD CYCLE COUNT key on the VGD SETPOINTS Screen.
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