JOHNSON CONTROLS
42
FORM 160.79-O3
ISSUE DATE: 11/09/2018
SECTION 2 – OPTIVIEW CONTROL CENTER
This screen displays a cutaway of the chiller compres-
sors, revealing the impellers. Animation of the impel-
ler indicates when the compressor is running. Several
compressor related conditions are shown. This screen
also serves as a gateway to subscreens for Capacity
Control, Surge protection and the Oil Sump.
DISPLAY ONLY
Oil Sump Temperature
Displays the temperature of the oil in the Sump.
System Oil Return Solenoid (LED)
Illuminates when the solenoid is energized.
HGBP Command
Displays the value of the Hot Gas Bypass Valve com-
mand over the range of 0% (closed) to 100% (fully
open). Only displayed if Hot Gas Bypass feature has
been enabled on the OPERATIONS Screen.
Lead Compressor
Displays which compressor has been selected as the
lead compressor. The lead compressor is selected upon
receipt of a start signal. The compressor that has the
least amount of run time that is ready to run is selected
as the lead compressor.
Compressor 1
Oil Pressure
Displays the pressure differential between the Pump
Oil Pressure transducer for compressor #1 and the
common Sump oil pressure transducer. If either of
these transducers are out of range, the display field
will show XX.X PSID. The displayed value includes
the offset pressure derived from auto-zeroing during
the system pre-lube period. The offset pressure is the
pressure differential between compressor #1 Pump Oil
Pressure Transducer and the Sump Oil Pressure trans-
ducer outputs during a three (3) second period begin-
ning ten (10) seconds into the system pre-lube period.
During this time, the transducers are sensing the same
pressure and their outputs should indicate the same
pressure. However, due to accuracy tolerances in trans-
ducers, differences can exist. Therefore, to compensate
for differences between transducers and assure differ-
ential pressure sensing accuracy, the offset pressure is
subtracted algebraically from the differential pressure.
The offset pressure calculation is not performed if ei-
ther transducer is out of range. The offset value is taken
as 0 PSI in this instance. If compressor #2 is already
running when bringing compressor #1 online, the off-
set calculation used will be that which was calculated
during compressor #2 pre-lube.
MAIN COMPRESSOR SCREEN
LD27848
FIGURE 9 -
MAIN COMPRESSOR SCREEN