The symbols established in this part of IS0 3511 have been developed to be used in conjunction with the symbols given in IS0 3511/l and IS0 3511/2 and shall be considered as supplementary.
They are intended to provide a means of illustrating process computer and/or shared display/control functions in the field of process measurement and control and may be used with the symbols of IS0 3511 /l and IS0 3511/2. They will enable users
to show and identify in simple form the functions of instruments, the process computer, and shared display/control functions, or any combination of these.It is permissible to use the basic symbol for computer-based functions (see 3.1) throughout for any software-based digital system. This is not intended to preclude the use of the basic
symbol for shared display/control functions (see 3.2) if the user considers this to be appropriate.
The symbols are intentionally limited to identification on process flow diagrams, piping and instrument diagrams, etc. and do not provide means of illustrating specific instruments or parts thereof.
The letter code for function identification shall be taken from table 1 of IS0 3511/l and IS0 3511/2.
The application methods are shown in the examples.