York YST Operation Manual page 44

SECTION 2 - OPTIVIEW CONTROL CENTER INTRODUCTION
inlet pressure
Displays the steam pressure measured at the inlet of
the turbine.
inlet Temperature
Displays the steam temperature measured at the inlet
of the turbine .
leaving Steam Condenser liquid
Temperature
Displays the colling liquid temperature measured at the
outlet of Steam Condenser.
governor valve
Displays the present control signal being sent to the
analog output controlling the pneumatically actuat-
ed turbine governor valve. This valve modulates the
steam inlet flow to the turbine to control the speed at
the value shown in the Speed Setpoint display. A 100%
value represents a command for the valve to open fully.
vacuum Solenoid (led)
Illuminates when the vacuum breaker solenoid valve is
energized to open the turbine exhaust to atmospheric
pressure.
Trip Solenoid (led)
Illuminates when the Turbine Trip Valve air dump so-
lenoid valve is energized to open the turbine trip valve.
Turbine rotation (led)
Illuminates when the turbine shaft begins to rotate as
sensed by the Turbine Rotating (Speed Switch) digital
input.
Trip valve limit Switch (open/Closed)
Displays the status of the limit switch sensing the
closed position of the pneumatically actuated turbine
trip valve. The status will change from Open to Closed
after the Trip Solenoid LED illuminates indicating that
limit switch contacts are closed and the valve is open.
44
nozzle #1 Solenoid (led)
Illuminates when the Turbine Nozzle Valve #1 Air
Dump Solenoid Valve is energized to open that turbine
nozzle valve. This object only appears if MSSP16-Tur-
bine Nozzle Solenoids is set for Enabled or MSSP4-
Turbine Start Mode is set for Auto on Configuration
Screen 1. See Figure 17 on page 46.
nozzle #2 Solenoid (led)
Illuminates when the Turbine Nozzle Valve #2 Air
Dump Solenoid Valve is energized to open that turbine
nozzle valve. This object only appears if MSSP16-Tur-
bine Nozzle Solenoids is set for Enabled or MSSP4-
Turbine Start Mode is set for Auto on Configuration
Screen 1. See Figure 17 on page 46.
Steam ring drain Solenoid (led)
Illuminates when the digital output controlling the Tur-
bine Steam Ring Drain Solenoid Valve is energized to
open the drain line and allow any water that may have
condensed inside the turbine to drain out.
prograMMable
begin Slow roll
Access Level Required: OPERATOR
This key is used to initiate the turbine slow roll warm-
up sequence only if the MSSP4-Turbine Start Mode
is set for Manual on the Configuration Screen 1. It
appears only after the chiller start has been initiated, the
pre-lube has been completed, and the turbine trip valve
limit switch input has closed. Pressing this key causes
the speed setpoint to increase to the SSP1-Slow Roll
Speed setpoint shown on the Speed Setpoints Screen at
the RRSP3-Slow Roll Ramp Rate shown on the Ramp
Rate Setpoints Screen. This causes the output signal to
the governor valve transducer to increase to open the
governor valve. After the key has been pressed, this
object disappears.
FORM 160.67-O1
ISSUE DATE: 4/1/2015
JOHNSON CONTROLS