York YK-EP Operation And Maintenance Manual page 47

Table 29: Display only
Field/LED
Access level
name
Oil Pressure
Pre-Rotation
Vanes
Closing LED
Vane Motor
Switch (LED)
PRV Position
PRV
Command
Phase A, B, C
Current
Full Load
Amps
Motor Run
(LED)
Compressor
Service
Status
YK-EP Style B Centrifugal Chiller
Description
Displays the pressure differential between the high sideoil pressure
transducer (compressor bearing input) and the low side oil pressure
transducer (oil sump). The displayed value includes offset pressure
derived from auto-zeroing during the System Prelube. If either of
the transducers used to calculate this differential is out of range, the
display field will show XX.X.
The offset pressure is the pressure differential between the high
oil pressure (HOP) transducer and the low oil pressure (LOP)
transducer outputs during a three (3) second period beginning
–
ten (10) seconds into the System Prelube. During this time, the
transducers will be sensing the same pressure and their outputs
should indicate the same pressure. However, due to accuracy
tolerances in transducer design, differences can exist. Therefore,
to compensate for differences between transducersand assure
differential pressure sensing accuracy, the offset pressure is
subtracted algebraically from the differential pressure. The offset
pressure calculation will not be performed if either transducer is out
of range. The offset value will be taken as 0 PSI in this instance.
– Displays when the Economizer PRV is closing.
– Indicates when the vanes are completely closed.
This value displays the present position of the Pre-Rotation vanes as
–
a percentage between 0 and 100%.
Indicateswhat percentage the panel is commanding the Pre-
–
Rotation Vanes to open.
Displays the 3-phase motor current values being read from the Solid
–
State Starter.
Displays the motor current as a percentage of the Full Load Amps
–
(FLA) value.
– Illuminates when the Primary Compressor is currently running.
This value displays the economizer compressor status. The values
are as follows:
• Stopped
• Prelube
• Running
• Soft Shutdown
• Coastdown
47