Proportional Control Solenoid Valves
A proportional solenoid valve delivers variable output flow from a corresponding input current applied to its solenoid. It regulates media flow in proportion to the electrical current applied to actuate the valve. That mechanism allows for precision flow control and electronic adjustments of pressurized gas, air and liquids. In a closed-loop system, a proportional control solenoid valve can precisely respond and maintain downstream pressure or flow.
How Proportional Valves Work
An electrical signal is sent to the solenoid coil, which generates an electromagnetic field that attracts the valve’s plunger. That magnetic field moves the plunger once it overcomes the force of the return spring holding it in place.
The plunger moves in response to the electrical stimulation, allowing it to gradually open or close the valve’s port. Some proportional solenoid valves also have pressure and flow sensors that send feedback to the coil to make necessary and precise adjustments. That creates repeatable performances for millions of cycles.
Types of Proportional Control Solenoid Valves
Small 2-Port Proportional Solenoid Valves
Our miniature ProControl™ PV3 and higher flow PV10 proportional solenoid valve models are available in inline-direct piping and subbase-manifold piping types, in 12VDC and 24VDC control voltages. The 10-32 UNF ported valves come with factory-calibrated standard pressure settings of 25, 50, 75 or 100 psi.
Large 2-Port Proportional Solenoid Valves
The compact PC30 ProControl™ proportional control valve delivers precise flow control up to 225 SLPM. The 1/4 PIPE models are available in inline-direct piping and subbase-manifold mount construction. Standard valve designs are calibrated to 25, 50 and 100 PSI maximum pressure settings in 12VDC and 24VDC voltages.
Specialty Proportional Valves
Humphrey offers a precise balanced proportional solenoid valve that provides high-flow and low-pressure capabilities. Originally developed for patient ventilation equipment, this customizable design maintains plunger position regardless of pressure fluctuations.
Our MiDP Proportional Valve is operated by a stepper motor and features a separate diaphragm that isolates inert and aggressive gas and liquid media from the valve operator. This variable flow controller can handle difficult media and is customizable for specific applications.
Customization and Engineering Support
In addition to standard models, Humphrey Products offers custom proportional valve solutions. Our services include engineering consultations to assess your unique application specifications and tailor the valve’s settings to your exact pressure, flow, gain and shut-off requirements.
Customization and Engineering Support
Proportional Solenoid Valve Driver
The ProControl™ PCD is designed to drive proportional solenoid valves directly, via PWM or with constant current signals. It’s perfect for bench-top testing solenoid valves or simple fixtures that require variable output flow control. The hardware is encased in a compact handheld control box and can interface with various data acquisition systems or be controlled manually.
Key Technical Specifications
Each proportional control solenoid valve provides excellent repeatability, low hysteresis, fast responses and tight sealing. Their compact design makes them ideal for applications with limited space and unique configurations.
Small 2-port proportional valve specs:
- Function: Single solenoid, normally closed
- Media: Air and inert gas
- Flow coefficient: 0.015 and 038 Cv
- Maximum flow: 30 and 75 LPM
Large 2-port proportional valve specs:
- Function: Single solenoid, normally closed
- Media: Air and inert gas
- Flow coefficient: 0.11 to 0.34 Cv
- Maximum flow: 225 LPM
Common Applications
With selectable, incremental or dynamic media flow control, ProControl™ Proportional Valves can be applied to market segments such as:
- Medical and lab equipment
- Analytical instruments
- Chemical testing and processing
- Industrial controls
- Factory and process automation
- Pressure regulation
Browse Our Selection of Proportional Control Solenoid Valves
Explore our extensive catalog of proportional control solenoid valves to find the right solution to suit your application. Contact our expert team if you need assistance or specialty designs.
FAQs
Proportional control valves can last up to 20 million cycles of continuous service.
A 2-way on/off solenoid valve opens or closes completely to its full flow capacity upon actuation. A proportional solenoid valve can open or close partially or gradually. It can also make fine adjustments in flow with minor changes to the electrical current while open.
While both valves offer proportional media flow control, servo valves are designed for applications that require extreme precision and responsiveness. They also feature more complex internal closed-loop construction and come at a much higher price point than proportional control solenoid valves. For greater precision and responsiveness, proportional control solenoid valves require external closed-loop feedback.