Which device converts current into pressure as part of a control signal?

• A. Converts current to pressure.
• B. Converts pressure to flow.
• C. Converts voltage to current.
• D. Converts temperature to resistance.

Answer: (A)

Converting a current signal into a pneumatic pressure signal is a common way to drive pneumatic actuators in control systems. In many loops, the control information travels as a current, typically 4–20 mA, which is robust over long runs. The device that handles this signaling is a current-to-pressure transducer (I/P transducer). It receives the loop current and outputs a proportional air pressure, which then positions a valve or actuator accordingly. This is exactly what the item is asking for: a device that turns current into pressure as part of the control signal.

The other concepts described don’t fit this need. Converting pressure to flow relates to how pressure drives fluid movement, not converting an electrical signal. Converting voltage to current is a pre-conversion step to prepare a signal for transmission, not the final current-to-pressure action. Converting temperature to resistance describes a sensor response for measuring temperature, not generating a pressure signal for control.