Proportional Solenoid Valves: How They Work & Advantages

Humphrey ProControl™ Proportional Solenoid Valves are an excellent option for pneumatic applications that require variable or controlled valve output flow.

Proportional Solenoid Valves – How They Work

Proportional valves are small two-port, normally closed, direct-acting solenoid valves. They respond precisely to the amount of input current applied to its solenoid. From a stabilized upstream pressure source, customers can expect precise and consistent variable output flow performance for millions of cycles. Output flow adjusts precisely to minor changes in input current.

Proportional valves can enhance pneumatic system performance with soft starts, precision stops, and reduced shock during operation. In closed-loop systems, proportional valves will deliver precise flow control and instantaneous response, even with minute adjustments from input sensors.

The ProControl™ Offering

Today, Humphrey offers three standard valve models and two customizable valve platforms from our Engineered Solutions group. Standard models:

Modifications to standard valves are possible and welcomed. Humphrey can optimize valve performance with an understanding of OEM customer requirements. Contact

The ProControl™ Servoid Series are tailored to specific customer requirements. Featuring very high flow from a low supply pressure source, the Servoid Series can deliver extremely precise and linear output flow with low hysteresis and high-resolution characteristics.

Proportional Solenoid Valve Drivers

Most OEM customers drive proportional valves from their onboard PCB. For others, Valve Drivers are available and are used to take input signals sourced from sensors and deliver appropriate output current to operate the solenoid. Customers use drivers to test, evaluate and use proportional valves on benchtops or in proportional valve projects. Humphrey offers it’s driver with the ProControl™ PCD.

Advantages of Proportional Solenoid Valves

  • Consistent operation without voltage changes
  • Tight seal at rest
  • Low hysteresis
  • Low power consumption
  • Excellent resolution
  • Compact construction

Check out our video breakdown for more information. Contact us to learn more about our products.