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A circle on a stem with a pointer or letters, marking a pressure indicator.
Also known as: Instrument bubble, PI instrument code, Circle with letters on a pipe
A circle on a short stem marks an instrument. The letters inside say what it measures and what it does — PI for pressure indication, PT for a transmitter — so the circle is a container for a code rather than a picture.
Marks an instrument measuring pressure at that point in the system, drawn as a circle joined to the pipe by a short stem.
Contexts: Technical drawing
Carries a letter code stating what is measured and what the instrument does, so PI is a pressure indicator and PT a pressure transmitter.
Contexts: Technical drawing
Uses the line style of its stem to say where the instrument is mounted and how its signal travels — a solid line for a local gauge, a dashed one for an electrical signal.
Contexts: Technical drawing
A circle joined by a short straight stem to a pipeline, with one or two capital letters written inside it and sometimes a horizontal line across its middle.
A fuller structured visual breakdown is not yet documented for this symbol.