Part I of this International Standard establishes a symbols system for use in depicting the basic functions of measurement and control equipment in relation to the plant with which it is associated. The system has been intentionally limited to the identification of instrument functions and does not provide means of illustrating specific instruments.
IS 12754 Pt.1-1989 history
1990IS 12754 Pt.1-1989 Process Measurement Controls, Functions and Instrumentation - Symbolic Representation Part 1 Basic Requirements