Electronic pressure regulators have many advantages over mechanical regulators. A mechanical regulator will maintain pressure downstream, most effectively with constant flow rates. However, downstream flow and pressure will often fluctuate in most applications. Pumps and compressors deliver pulses, and the pressure will fluctuate with demand. When a mechanical pressure regulator lacks accuracy or can’t respond fast enough, the result is uneven pressure output. This simple device might be good enough when accuracy isn’t as crucial. However, an electronic/digital pressure regulator delivers better accuracy and dynamic output pressure regulation by utilizing a control signal and the feedback signal to create closed-loop pressure control.
What They Do
Electronic pressure regulators maintain a constant output pressure within a pressurized system even if there are fluctuations in the incoming pressure to the regulator. Mechanical pressure regulators are typically only adjustable by hand, limiting their usability in high tech applications. When using an electronic pressure regulator with a digital control system, the precise output pressure is controllable via slight adjustments to the control signal. An internal pressure transducer creates a true closed-loop control device and offers a feedback voltage of the current output pressure. By reading this feedback signal from an electronic regulator, control systems can make real-time adjustments, greatly improving consistent pressure regulation in the most demanding applications.
How Electronic Pressure Regulators Work
Electronic pressure regulators are a big improvement over mechanical regulators—they are fairly simple and very effective at allowing better control. They use a fill valve and a vent valve to maintain the outlet pressure at the desired set-point. A small inner pressure sensor monitors the output pressure and the digital controller adjusts the flow output of the internal valves to retain the required set-point (i.e. closed-loop control). That means that when you set the desired pressure, the regulator will maintain this pressure even with changing flow rates through the system. The internal pressure transducer gives immediate feedback to adjust the flow of either the fill or vent valve so the output pressure remains static.
When the control signal increases, the internal proportional valve activates, increasing pressure into an internal pilot chamber. When this happens, more of the inlet pressure passes through the proportional fill valve and into the pilot chamber. The pressure in the pilot chamber grows and causes the upper surface of the diaphragm to operate. Because of this, the air supply valve linked to the diaphragm opens, and a portion of the supply pressure becomes output pressure. This output pressure goes back to the control circuit using the pressure sensor. The fill valve will continue to slightly adjust until the output pressure is equivalent to the desired set-point of the control signal.