Compressor Screen; Figure 14 - Compressor Screen (Screen Shown Is A Unit With Proximity Probe) - York YK Style H Operation Manual

FORM 160.76-O2
issue date: 6/15/2015

FIGURE 14 - COMPRESSOR SCREEN (SCREEN SHOWN IS A UNIT WITH PROXIMITY PROBE)

OVERVIEW
This screen displays a cutaway view of the chiller com-
pressor, revealing the impeller, and shows all condi-
tions associated with the compressor. In addition, with
the proper access level, the Pre-rotation Vanes may
be manually controlled. Animation of the compressor
impeller indicates whether the chiller is presently in a
RUN condition. This screen also serves as a gateway
to subscreens.
Requires a login access level of SERVICE.
Service Technicians refer to the OptiView
Control Center - Service Instructions
(Form 160.76-M1) for operation instruc-
tions and explanation of all programmable
setpoints and displayed values.
DISPLAY ONLY
Oil Pressure
Displays the pressure differential between the high
side oil pressure transducer (compressor bearing input)
and the low side oil pressure transducer (oil sump). The
JOHNSON CONTROLS
SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION

COMPRESSOR SCREEN

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 ex-
ist. Therefore to compensate for differences between
transducers and assure differential pressure sensing ac-
curacy, the offset pressure is subtracted algebraically
from the differential pressure. The offset pressure cal-
culation will not be performed if either transducer is
out of range. The offset value will be taken as 0 PSI in
this instance.
LD19452
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