Johnson Controls York YKEP Series User Manual

FORM 160.77-O2
ISSUE DATE: 11/15/2011
JOHNSON CONTROLS
76
SECTION 3 - YKEP CONTROL PANEL OPERATION
ECONOMIZER COMPRESSOR SCREEN
FIGURE 40 - ECONOMIZER COMPRESSOR SCREEN
LD15401
The offset pressure is the pressure difference between
the high oil pressure (HOP) transducer and the low oil
pressure (LOP) transducer outputs During this time,
the transducers should be sensing the same pressure.
However, due to accuracy tolerances in transducer de-
sign, differences may exist in these pressure readings.
To compensate for these differences between transduc-
ers and assure differential pressure sensing accuracy,
the offset pressure is subtracted algebraically from the
oil (differential) pressure value. The offset pressure
calculation will not be performed if either transducer
is out of range and the offset value will be 0 PSI in this
instance.
Oil Sump Temperature
Displays the temperature of the oil in the sump (pro-
vided by RTD TE-140).
Discharge Temperature
Displays the temperature of the refrigerant (in a gaseous
state) at discharge of the compressor before the refriger-
ant enters the condenser (provided by RTD TE-113).
OVERVIEW
This screen displays a background cutaway view of
the chillers Economizer Compressor, revealing the
impeller and also shows all conditions associated with
the compressor. The pre-rotation vanes may be manu-
ally controlled from the appropriate access level. This
screen also serves as a gateway to sub-screens for cali-
brating the Pre-rotation Vanes, and the Variable Geom-
etry Diffuser.
DISPLAY ONLY
Oil Supply Pressure
Displays the pressure differential between the high
side oil pressure transducer (HOP, located between oil
filter output and compressor bearing input) and the low
side oil pressure transducer (LOP, located between oil
sump and compressor housing). The displayed value
includes offset pressure derived from auto-zeroing
during the system prelube. The display field will show
XX.X when either of the transducers used to calculate
oil pressure are out of range. The zero function occurs
when the RESET button is pressed, the oil pumps are
not running, and there are no system faults or alarms.

Johnson Controls York YKEP Series Specifications

General

Brand	Johnson Controls
Model	York YKEP Series
Category	Chiller
Language	English