What does an I/P transducer do?

• A. A device that measures temperature
• B. A device used to convert an electrical signal into a pressure signal
• C. A device used to convert a pressure signal into an electrical signal
• D. A device that filters liquids

Answer: (B)

An I/P transducer translates an electrical control signal into a pneumatic pressure signal, so a controller output can directly drive a pneumatic valve or actuator. Typically the input is a current (for example 4-20 mA), and the device converts that current level into a proportional output pressure (such as 3-15 psi or 0-100 kPa). This enables electronic instrumentation to control pneumatic equipment since pneumatics respond to pressure rather than electrical signals. It does not measure temperature, nor does it convert pressure back into electricity—that would be a different type of transducer—as well as it isn’t used to filter liquids.