Equilibar offers a line of precision electronic pressure regulators to provide this pilot reference signal. The QPV ultra-resolution and the EPR-30Hg models have virtually no hysteresis or deadband, resulting in the capability to make precise adjustments.
These regulators can be used in open loop mode or closed loop mode. In open loop mode, the vacuum setpoint is commanded using a computerized signal sent to the electronic pilot regulator. The pilot regulator produces that commanded pressure onto the EVR reference port to keep the process vacuum very close to the setpoint value. Open loop mode will result in a slight variability in vacuum pressure as flow rates increase.
In closed loop, or PID mode, the process vacuum pressure is monitored by a separate pressure sensor close to the process, and the command signal sent to the pilot regulator is adjusted to bring that process pressure to match the desired setpoint. This PID action can be accomplished inside the QPV electronic pressure regulator, or in the existing process control system. Closed loop control will result in more accuracy over a wide range of flow rates.
Learn more about how our vacuum regulators work.
Contact an application engineer to discuss ways your process can benefit from electronic vacuum control.
Electronic Vacuum Regulator Details
This table details Equilibar Vacuum Regulators with inlet port sizes from 1/4″ to 1″.
Equilibar also offers electronic vacuum regulators in port sizes from 1.5 to 4″.
Model | Inlet/Outlet Port | Reference Port | Standard Body Materials | Diameter | Height | Cv Range (precision) | Available End Fittings | ||
---|---|---|---|---|---|---|---|---|---|
(inch) | Min | Max | Std | Available | |||||
EVR-GSD2 | ¼” | 1/8″ | SS316 (std) Anodized Aluminum PVC | 3.0 | 1.3 | 1E-3 | 1.0 | NPT | 150# Flange BSP SAE VCO style VCR style |
EVR-GSD3 | 3/8″ | 3.5 | 1.35 | 1E-3 | 1.8 | ||||
EVR-GSD4 | ½” | 4.5 | 1.6 | 1E-2 | 3.2 | ||||
EVR-GSD6 | 3/4″ | 6.0 | 2.0 | 1E-2 | 5.5 | ||||
EVR-GSD8 | 1″ | 7.0 | 2.6 | 1E-2 | 8.5 |