Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

ISA Instrumentation Codes used in Process Control Systems

The ISA standards and symbols are important for the P&IDs and documents describing the process control system.

ISA Instrumentation Codes used in Process Control Systems
Process VariableSymbolType of InstrumentSymbol
Analyses A Alarm A
Burner B Users Choice B
Combustion B Controller C
Users Choice C Control valve CV
Users Choice D Trap CV
Voltage V Sensor (primary element) E
Flow Rate F Rupture disc E
Users Choice G Sight or gage glass G
Current (electric) I Monitor G
Power J Indicator I
Time K Control Station K
Level L Light (pilot/operation) L
Users Choice M Users Choice N
Users Choice

N

Flow Resistance Orifice O
Users Choice O Test point (sample point) P
Pressure / Vacuum P Recorder R
Radiation R Switch S
Speed (or Frequency) S Transmitter T
Temperature T Multifunction U
Multivariable U Valve/Damper V
Vibration V Well W
Weight (force) W Unclassified X
Unclassified X Relay Y
Event Y Driver Z
Position, dimension Z Actuator Z

Example - ISA symbols for a Level Indicator

A level indicator will receive the symbol "L" for the process variable "Level", and "I" for the "Indicator" type of instrument. Both combines to:

LI

For unique identification within a system it is common to add a number to the ISA code, by example the code for level indicator no. eight may be:

LI 08

Related Topics

Related Documents

Search

Search is the most efficient way to navigate the Engineering ToolBox.

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

Translate this Page

Translate this page to Your Own Language .

About the Engineering ToolBox!

Privacy Policy

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

Citation

This page can be cited as

  • The Engineering ToolBox (2003). ISA Instrumentation Codes used in Process Control Systems. [online] Available at: https://www.engineeringtoolbox.com/isa-iso-instrumentation-codes-d_37.html [Accessed Day Month Year].

Modify the access date according your visit.

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter

















































3.27.8

.