York YK-EP Operation And Maintenance Manual page 67

Table 53: Display only
Field/LED name
ACC Surge Detected (LED)
VGD Count
VGD Time
( __Days __Hrs __Min __Sec)
Control Status
Time Remaining
Table 54: Programmable
Button Access level
Surge React
PRV Offset
Probe Wait
Open Pulse
YK-EP Style B Centrifugal Chiller
Description
Only displayed if equipped with a VSD or MVVSD. 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 reset
with an ADMIN access level using the VGD CYCLE COUNT key on the
VGD SETPOINTS Screen.
Displays the accumulated time the Stall Detector Board output
voltage is greater than the High Limit Setpoint while the chiller is
running.
Displays the current state of the VGD control. The states are: Stall
Waiting, Stall Reacting, Probing, Surge Reacting, Surge Waiting, Hot
Gas Override.
While the VGD is in the Stall Waiting State, displays the time
remaining in the Probe Wait Time interval (value programmed as
the Probe Wait Time setpoint).
Description
1 to 30 seconds; default 5
–
Specifies the length of the close pulse applied to the VGD in
response to a surge.
0 to 5%; default 3
If the VGD control is in the Stall Waiting state and the Pre-Rotation
–
Vanes position changes by more than this value, the Probing state
will be entered. If the PRV Offset is set to 0%, the Stall Waiting state
is performed based only on the Probe Wait Time setpoint interval.
0.5 to 15 minutes; default 10
–
Specifies how long the VGD control remains in the Stall Waiting or
Surge Waiting states before entering the Probing state.
1 to 5 seconds; default 2
–
Specifies the length of the open pulse applied to the VGD during 10
second periods while in the Probing state.
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