Pneumatic signal
ISA 5.1-2009/2022 (instrument line symbols)
Drawn as
A thin line with pairs of short diagonal slashes (//) at intervals.
Meaning
Air signal, e.g. from an I/P or positioner to an actuator, or an instrument-air signal to a pneumatic controller. Not modelled.
Variants
- Older drawings (ISA 1984) used the same // marks
- Some legends use three slashes for electric (pre-1984)
Not physical hardware. Read it, then skip it in the 3D model.