P&ID General Instrument Symbols
  • A balloon by itself indicates a discrete stand-alone instrument, such as a:
  • Transmitter
  • Sensor
  • Alarm
UNIT 1
LOW TEMP		 UNIT 2
LOW TEMP		 UNIT 3
LOW TEMP
UNIT 1
HIGH TEMP		 UNIT 2
HIGH TEMP		 UNIT 3
HIGH TEMP

Transmitter

Sensor

Alarm

Back
2 of 11