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VSG/VSSG • Installation, Operation and Maintenance Manual •Vilter/Emerson • 35391STG
Section 1 • General Information
PDIT Pressure
Differential
Indicating Transmitter
PDSH Pressure
Differential
Switch High
PDSHH Pressure Differential
Switch High High
(Shutdown)
PDSL Pressure
Differential
Switch Low
PDSLL Pressure Differential
Switch Low Low
(Shutdown)
PDT Differential
Pressure
Transmitter (Blind)
PDV Pressure
Differential
Control Valve (Pneumatic
Actuator)
PFY
Pressure Ratio Convertor/
Relay
PFC
Pressure Ratio Controller
PG Pressure
Gauge
PI
Pressure Indication (Soft)
PIC Pressure
Indicating
Controller
PIT Pressure
Indicating
Transmitter
PSE
Pressure Rupture Disk
PSH
Pressure Switch High
PSHH Pressure Switch High High
(Shutdown)
PSL
Pressure Switch Low
PSLL Pressure Switch Low Low
(Shutdown)
PSV
Pressure Safety Relief
Valve
PT Pressure
Transmitter
(Blind)
PV
Pressure Control Valve
Q
Quantity and Heat
QE Heater
Element,
Immersion, Tracing
R Radiation
S Speed,
Frequency
SC Speed
Control
SD Shutdown
SIC Speed
Indicating
Controller
T Temperature
TC Temperature
Controller
TAH Temperature
High
TAHH Temperature High High
(Shutdown)
TAL Temperature
Low
TALL Temperature Low Low
(Shutdown)
TE Temperature
Element
(RTD, Thermocouple,
etc.)
TG Temperature
Gauge
TI Temperature
Indication
(Soft)
TIC Temperature
Indicating
Controller
TIT Temperature
Indicating
Transmitter
TRV
Transfer Valve 3-Way
TSH
Temperature Switch High
TSHH Temperature Switch High
High (Shutdown)
TTSL Temperature Switch Low
TSLL Temperature Switch Low
Low (Shutdown)
TT Temperature
Transmitter
(Blind)
TV Temperature
Control
Valve
TW Temperature
Thermo-well
TY Temperature/Relay/
Convertor
U Multi
Variable
V Vibration,
Mechanical
Analysis
VE Vibration
Probe
VFD
Variable Frequency Drive
VG
Block/Bleed, Gauge Valve
VSH
Vibration Switch High
VSHH Vibration Switch High
High (Shutdown)
VT Vibration
Transmitter
(Blind)
VU Vibration
Monitoring
System
W Weight
XA Status
(Stopping/Not
Running) Alarm/Common
Alarm
XC State
Controller
XI Running
Indication
XV Solenoid
Valve
XY State
Relay/Convertor
Y
Event, State, Presence
YAH Fire
Alarm
YE
Fire Detecting Sensor
YIT
Fire Indicate and Transmit
YK
Fire Control Station
Z Position,
Dimension
ZC Position
Controller
ZE Position
Element
ZI Position
Indicator
ZIT Position
Indicating
Transmitter
ZT Position
Transmitter
(Blind)
ZY Position
Transmitter
(Blind)
ZZ Position
Actuator
(Capacity or Volume)