Description
The Alicat PCD dual valve pressure controller utilizes independently controlled intake and exhaust valves to achieve fast and stable pressure control inside a closed, or dead headed, system. Proprietary control software and electronics allow the PCD controller to input process gas into a chamber and also exhaust process gas. The PCD pressure controller has been used in a variety of industries ranging from semiconductor manufacturing to biopharmaceutical testing.
The PCD pressure controller was created in response to the need for fast, accurate, repeatable and cost effective pressure control instrumentation designed specifically for closed volumes. Historically, closed volume pressure control was done by using a pressure controller or switch and a bleed port. This method, although effective, resulted in wasted process gas, poor repeatability, and poor accuracy.
Benefits
Speed and Control
By utilizing modified PID loop controls and proportional control, the PCD pressure controller is able to quickly and accurately reach a defined setpoint. Since the PCD uses similar control algorithms as those in the PC Series single valve pressure controllers, the control speed of the PCD is measured at less than 1/10th of a second!
Cost Savings
The PCD series pressure controller uses only one valve at a time automatically switching the PID control to the required valve. By opening and closing one valve at a time, gas venting required to maintain a setpoint is significantly reduced. Less exhausted gas is less wasted gas. Companies using exotic bottled gases could save thousands of dollars a year by switching to a PCD pressure controller.
Accuracy
The PCD uses a modified PID closed loop control and a proportional control on each valve resulting in a total full scale accuracy of +/- 0.25% for most units. Optional higher accuracy is available for more demanding applications. The modified loop and proportional control not only produces increases in precision control of the process pressure in closed or nearly closed systems, it also eliminates dead-band that is inherent in other pressure controllers that use pressure switches and on/off valves.
Repeatability
Processes designed for consistency require instrumentation that is repeatable. The PCD series dual valve pressure controller has an impressive repeatability spec of +/-0.08% of full scale.
All Alicat PCD series dual valve pressure controller calibrations are NIST traceable.
Features
Alicat PCD series pressure controllers come standard with the following options:
- Fully functional digital display with pushbutton control
- No warm up time
- Viton seals
- 8 pin mini din electronic connector
- Standard barrel type power connector
- RS-232 Multi-drop digital output
- RS-232 Multi-drop digital input
- Choice of 0-5Vdc, 0-10Vdc, or 1-5Vdc analog output
- Choice of 0-5Vdc, 0-10Vdc, 1-5Vdc, or 4-20mA analog input
- User tunable PID algorithm
- Multiple digital & analog input/output
- 200:1 turndown ratio allow gauge to measure 1/200th of its full scale potential
- User can select any of nine units of measure at time of order
- Setpoint control and loop tuning via display
- Able to operate in applications with flow rates as high as 2500SLPM.
- Compatible with a variety of gases and liquids
- NPT process connections
- Lifetime warranty
Optional features and equipment
- High accuracy calibration
- Locking 6 pin, DB9 or DB15 connector
- DeviceNet™ digital input/output
- ProfiBUS digital input/output
- RS-485 digital input/output
- 4-20mA analog output
- Color backlit TFT display
- Remote panel mount display
- Remote panel mount color backlit TFT display
- Acrylic Mil-spec dielectric conformal coating
- EPDM seals
- NeSSI flow body
- Oxygen cleaned
- Remote electronic package for high temp environments
- SAE process connections
- VCR, VCO style welded fittings
- 5VDC, 12VDC, 24VDC, or open drain flow alarms (high or low)
- Additional calibration points
- Stainless steel valves
- High flow, low drop valve
- Internal potentiometer control
- CSA or ATEX certification