What is a Proportional Solenoid Valve?

A proportional solenoid valve uses a control signal (DC current) to control the flow of media  through a particular valve.

Unlike traditional on/off solenoid valves, a proportional valve controls flow rates in a variable fashion based on the electrical current applied to the solenoid. This “meters” the flow rate through the valve proportionally to the electrical signal to the solenoid.

Common Features of a Proportional Solenoid Valve

Variable flow control: Proportional valves regulate flow rates in a linear fashion, offering flexibility in managing the media flow within a system.

Proportional response: Proportional valves respond efficiently to changes in the input signal. This proportionality allows accurate flow adjustments to meet specific operational requirements.

Wide range of control: Proportional valves are compatible with a broad range of media, flow rates, inlet pressures and temperatures, making them adaptable to diverse application needs.

Consistent performance: Proportional valves maintain their performance from zero flow to max flow over millions of cycles. This helps ensure reliability and stability during operation.

Low hysteresis: Precision proportional valves reduce the lag time between signal input and reaching the desired flow rate.

Compact design: This type of proportional valve is small and lightweight. It’s suitable for systems with strict space requirements or when multiple valves are needed in a manifold assembly.

Proportional Solenoid Valve Features & Specifications

Humphrey’s ProControl™ proportional solenoid valves can operate:

  • Dynamically for continuous high-frequency adjustments (closed-loop responses).
  • Incrementally with pre-determined low-frequency adjustments within each cycle.
  • Selectable with cycle-to-cycle selected output flow as prescribed.

Small 2-port proportional solenoid valve specs:

  • Available in PV3 & PV10 family
  • Function: Normally closed 2-port
  • Flow coefficient: 0.015 to 0.018 Cv
  • Maximum flow: 18 to 30 LPM
  • Port size: 10-32 UNF and M 5 x 0.8

Large 2-port proportional solenoid valve specs:

  • Function: Single solenoid proportional, normally closed
  • Flow coefficient: 0.441 Cv
  • Maximum flow: 200+ LPM
  • Port size: ¼ NPT

Benefits of Proportional Solenoid Valves

Low power consumption: Proportional valves require only enough electrical power to adjust the valve opening to the desired position and flow rate, reducing energy consumption.

Low leak rate: Proportional valves have a tight sealing mechanism that reduces the leak rate during operation. The high-quality elastomers withstand harsh operating environments and media while maintaining seal integrity.

Reduced wear and tear: Unlike on/off solenoid valves, proportional solenoid valves operate with less mechanical stress which can help extend their lifespan and provide cost savings.

Common Applications

Proportional solenoid valves are suitable for applications where precise flow control is essential, such as pneumatic systems and industrial automation.

With selectable, incremental or dynamic control of media flow, ProControl™ proportional valves are used in market segments such as:

  • Medical
  • Analytical
  • Testing
  • Instrumentation
  • Factory and process automation

Humphrey Products ProControl Series

Our ProControl Valve series and proportional solenoid valve driver can help deliver precise variable flow control for various unique applications. For more information, check out this article on 5 Considerations When Choosing a Proportional Valve.

For assistance choosing a proportional valve for your application, contact our Proportional Valve experts at 844-447-9009 or send us an email.

A Humphrey ProControl™ Solenoid Valve Driver