Which of the following is a primary function of a regulator in a pneumatic system?

• A. It stores compressed air for emergency use.
• B. It converts electrical power to pneumatic power.
• C. It maintains a set pressure and regulates flow to actuators.
• D. It serves as a filter to remove contaminants.

Answer: (C)

A regulator in a pneumatic system is used to set and hold a specific downstream pressure and to modulate the airflow to the actuators as needed. It senses the pressure on the output side and adjusts the valve opening so the downstream pressure stays at the preset level, even as supply pressure or actuator demand changes. This keeps actuator speed and force consistent and protects components from over- or under-pressurization.

Storing compressed air is the job of a reservoir, not a regulator. Converting electrical power to pneumatic power is done by a compressor, not a regulator. Filtering contaminants is the role of an air filter (often with separators), not the regulator.