A differential pressure transmitter installation used for level measurement in which the low side of the transmitter piping remains empty is called which term?

A differential pressure transmitter installation used for level measurement in which the low side of the transmitter piping remains empty is called which term?

• A. dry leg
• B. wet leg
• C. open leg
• D. closed leg

Answer: (A)

In differential pressure level measurement, two legs carry pressure from the process to the transmitter. When the low side piping is not filled with process liquid and remains empty (gas-filled), that condition is called a dry leg. The empty low side means the transmitter is reading the pressure from the liquid column in the other leg while the reference leg is dry, which is why this term fits. If the leg were filled with liquid, it would be a wet leg. The other terms don’t describe an empty leg in this setup.

In differential pressure level measurement, two legs carry pressure from the process to the transmitter. When the low side piping is not filled with process liquid and remains empty (gas-filled), that condition is called a dry leg. The empty low side means the transmitter is reading the pressure from the liquid column in the other leg while the reference leg is dry, which is why this term fits. If the leg were filled with liquid, it would be a wet leg. The other terms don’t describe an empty leg in this setup.