Food Engineering

Proportional pneumatic controller

April 4, 2003




This new closed-loop, proportional pneumatic controller for use with air-loaded valves is designed for processes that depend on precise pressure control. The Series PRS maintains downstream pressure with virtually no deviation in spite of large variations in flow rate, unlike ordinary regulators. The PRS , called the Stabilizer, features a Teflon diaphragm in a thermoplastic connection, with no wetted metals or elastomers, specifically for use with ultra-pure deionized water systems of highly corrosive chemicals. It is simply installed in the piping system at the desired point of control, and connected to the regulator with common square-in. pneumatic tubing. An adjusting screw is used to dial in the desired pre ssure. Whenever pressure at the diaphragm exceeds the set point, the Stabilizer reduces control pressure to the regulator, which in turn begins to close and reduce process pressure; control pressure is increased if process pressure falls below the set point. Plast-O-Matic Valves, Inc., Cedar Grove, NJ 07009. Tel (973) 256-3000; fax (973) 256-4745; www.plastomatic.com
Product 236