View Tameson’s selection of digital controllers for controlling valves. They are best suited for controlling proportional solenoid valves, as they can control the plunger position between 0-100%. Most controllers are capable of doing this by converting a 4-20 mA, 0-20 mA, 0-5 V or 0-10 V signal into a pulse width modulation (PWM) signal, which allows for greater control, accuracy, and less hysteresis when controlling these valves compared to a variable DC signal. Some controllers can also control standard process, control, and motor valves. A controller like the Burkert 8605 uses an open loop system by taking an input signal and outputting a PWM signal to change the valve’s plunger position and orifice opening. The Burkert 8611 uses a closed loop system with feedback of the measured parameter (flow rate, temperature, etc.) to automatically change the PWM signal controlling the solenoid valve. Burkert offers versatile PWM controllers that come pre-programmed with Burkert valve parameters for easy installation (they can also be used with other brand’s valves). If you need assistance in selecting a controller, please read our article about proportional control or contact us.