Johnson Controls YORK YK MaxE, Operation Manual

Page: 57 / 184

FORM 160.54-O1
57
JOHNSON CONTROLS
2
VgD Time ( __Days __Hrs __Min __Sec)
Displays the accumulated time the Stall Detector Board
output voltage is greater than the High Limit Setpoint
while the chiller is running.
Control Status
Displays the current state of the VGD control. The states
are: Stall Waiting, Stall Reacting, Probing, Surge React-
ing, Surge Waiting, Hot Gas Override.
Time Remaining
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).
prograMMaBLe
Surge React
(1-30 seconds; default 5) - Specifies the length of the
close pulse applied to the VGD in response to a surge.
PRV Offset
(0-5%; 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 en-
tered. If the PRV Offset is set to 0%, the Stall Waiting
state is performed based only on the “Probe Wait Time”
setpoint interval.
Probe Wait
(0.5-15 minutes; default 10) – Specifies how long the
VGD control remains in the Stall Waiting or Surge Wait-
ing states before entering the Probing state.
Open Pulse
(1-9 seconds; default 2) – Specifies the length of the
open pulse applied to the VGD during 10 second periods
while in the Probing state.
High Limit
(0.5-1.2Vdc; default 0.8) – Specifies the Stall Detec -
tor Board output voltage that represents an acceptable
amount of stall noise.
The minimum difference between the High Limit
setpoint and the Low Limit setpoint is 0.1 vdc. If a
Low Limit setpoint is entered which is less than 0.1vdc
below the High Limit setpoint, the High Limit setpoint
is adjusted so that it is 0.1VDC above the newly entered
Low Limit value.
Low Limit
(0.4-0.8VDC; default 0.6) – in the Stall Reacting State,
the VGD is driven closed until the Stall Detector Board
output voltage decreases to this level.
The minimum difference between the High Limit
setpoint and the Low Limit setpoint is 0.1VDC. If a
Low Limit setpoint is entered which is less than 0.1VDC
below the High Limit setpoint, the High Limit setpoint
is adjusted so that it is 0.1VDC above the newly entered
Low Limit value.
VgD Count
Access Level required : ADMIN
Allows the user to clear the VGD Cycle Count.
Extreme Stall Duration
(Software version C.MLM.01.14.xxx (and later) or
C.OPT.01.14.306 (and later))
(10 to 20 minutes; default 10) – Specifies the maximum
allowed time an extreme stall condition can exist before
the VGD operation is disabled and driven to the full open
position to protect it from damage.
NaVigatioN
Home
Access Level Required : Service
Causes an instant return to the Home Screen
VgD Screen
Access Level Required : Service
Causes an instant return to the Variable Geometry Dif-
fuser Screen