Instrument supply / process connection
ISA 5.1-2009/2022 (instrument line symbols)
Drawn as
A thin solid line from a process line or vessel to an instrument bubble (or from a supply header).
Meaning
Impulse line from the process to an instrument, or an instrument supply (air, power). It shows where the instrument is mounted. Not a numbered process line.
Variants
- ISA 5.1-2009 also uses a plain thin line for "undefined signal"
- Supply type may be written on it: AS (air supply), ES (electric), NS (nitrogen), HS (hydraulic)
No 3D component yet.