Skip to content

ISA 5.1 Compliance Traceability

Standard: ANSI/ISA-5.1-2009 Scope: Provides standard symbols for P&ID (Piping and Instrumentation Diagram) documentation used in the HMI symbol library. Coverage: Low (initial symbol set covers common instrumentation symbols) Status: In Progress

Requirements Traceability

Symbol ID ISA 5.1 Reference Description Category Status
valve-gate Table 4.6.1 Gate valve Valves Implemented
valve-globe Table 4.6.2 Globe valve Valves Implemented
valve-ball Table 4.6.3 Ball valve Valves Implemented
valve-butterfly Table 4.6.4 Butterfly valve Valves Implemented
valve-check Table 4.6.5 Check valve Valves Implemented
valve-control Table 4.6.6 Control valve Valves Implemented
valve-solenoid Table 4.6.7 Solenoid valve Valves Implemented
motor-electric Table 4.7.1 Electric motor Motors Implemented
motor-vfd Table 4.7.1 (var) Variable frequency drive motor Motors Implemented
motor-pump Table 4.7.2 Centrifugal pump Motors Implemented
vessel-tank Table 4.5.1 Cylindrical storage tank Vessels Implemented
vessel-reactor Table 4.5.2 Reactor vessel with agitator Vessels Implemented
vessel-column Table 4.5.3 Distillation column Vessels Implemented
inst-sensor Table 3.1, Cl. 5.1 Generic instrument (gauge/dial); fallback when the measured variable is unknown Instruments Implemented
inst-temperature Cl. 5.1 (first-letter T) Temperature instrument balloon (tag inside circle + field stem) Instruments Implemented
inst-pressure Cl. 5.1 (first-letter P) Pressure instrument balloon Instruments Implemented
inst-flow Cl. 5.1 (first-letter F) Flow instrument balloon Instruments Implemented
inst-level Cl. 5.1 (first-letter L) Level instrument balloon Instruments Implemented
inst-analytical Cl. 5.1 (first-letter A) Analytical instrument balloon Instruments Implemented
inst-speed Cl. 5.1 (first-letter S) Speed instrument balloon Instruments Implemented
inst-weight Cl. 5.1 (first-letter W) Weight instrument balloon Instruments Implemented
inst-transmitter, inst-controller, inst-indicator, inst-recorder, inst-valve-positioner — Deprecated function-based aliases (#639); kept resolvable for back-compat but render the generic gauge Instruments Deprecated
pipe-line Cl. 4.1 Process pipe line Piping Implemented
pipe-instrument-line Cl. 4.2 Instrument signal line (dashed) Piping Implemented
pipe-reducer Table 4.3.1 Pipe reducer Piping Implemented
pipe-tee Table 4.3.2 Tee junction Piping Implemented

Implementation

All symbols are implemented as pure SVG render functions in the HMI web UI.

The symbol library as the product serves it: a searchable gallery grouped by category, rendered live from the symbol registry with no symbol ID typed by hand.
The library in its working context: a live unit display drawn from declared-role process graphics on the operator's surface.

Features

  • State coloring: Each symbol supports ISA-88 state colors (Idle, Running, Complete, Paused, Held, Stopped, Aborted)
  • Theme-aware: Symbols use currentColor and adapt to the dark UI theme
  • Rotation: Optional rotation parameter for orientation variants
  • Labels: Optional tag labels rendered below the symbol
  • Measured-variable instrument balloons (#639, #652): An instrument with a known measuredVariable (set on the ControlModuleTemplate/ControlModule spec) renders as an ISA-5.1 balloon: a circle carrying the ISA tag, over an upside-down "T" field-connection stem. The first tag letter comes from the measured variable (ISA-5.1). When no variable is known the generic gauge is used, and no letter is implied.
  • Tag-letter shorthand (#639, #652): The derived ISA tag (e.g. TI, PC) rides inside the balloon, with no separate badge. First letter from the measured variable, second letter from function: I (Indicate, true by construction for anything on an HMI) or C (Control, for control loops). No tag is shown when the variable is unknown. Letters are never hardcoded.

The Symbol Library's detail panel for the control valve: the symbol rendered seven times in a row, once per ISA-88 state, each chip labelled idle, running, complete, paused, held, stopped, and aborted with its state-color stroke

The fermenter's HMI unit display with its two instrument elements rendered as ISA-5.1 balloons: the temperature element's balloon carries the derived TI tag and the level element's carries LI, each over its field-connection stem

Gap Analysis

  • Safety valve symbols not yet implemented
  • Heat exchanger symbols not covered
  • ISA-5.1 first-letter (measured variable) and the indicate/control succeeding letter are derived from real metadata (#639). The transmitter/element/recorder succeeding-letter distinction is intentionally not modeled, because it is a P&ID arrangement concern with no operator-facing meaning on an HMI
  • Tag identification is not yet validated programmatically (e.g. enforcing a legal first/succeeding-letter combination)
  • Shared control/display symbols (DCS, PLC bubbles) not yet included

Roadmap

  1. Add heat exchangers, filters, and compressor symbols
  2. Implement ISA 5.1 tag letter validation
  3. Add shared display/control symbols for DCS architecture diagrams
  4. Support connection point metadata for diagram wiring