May 22, 2009
Bray Controls has announced the Series 6A line of Intelligent Electro-Pneumatic Positioners. These microprocessor controlled positioners offer precise flow control and advanced digital communication. Utilizing proven technology, the Series 6A features reliability in the field plus the lowest air consumption on the market. For use with either double or single acting pneumatic actuators, the positioners can accept an analog 4-20 mA input or BUS intelligent HART, FOUNDATION Fieldbus™ or PROFIBUS PA input. Both waterproof (NEMA 4, 4X/IP66) and explosion proof (NEMA 4, 4X, 7 and 9) enclosures are offered. A waterproof stainless steel enclosure is available upon request. Piezo valve technology controls the air supply within the Series 6A, producing zero bleed during steady state and minimal consumption during operation. The energy savings alone can pay for the cost of the unit within a year. In addition, the power conservation and reduced noise are beneficial to the environment. An LCD display provides visual confirmation of valve position in precise one-degree increments. The positioner’s operating status and alarm messages are also shown. With the enclosure cover removed, keypad push buttons can easily perform a variety of functions, including automatic calibration, confirmation of the setpoint, progress to the setpoint, potentiometer alignment, diagnostic checks and error messages. The LCD display shows the information entered in the keypad. Auto Calibration is started by only entering three parameters into the keypad. Auto Calibration quickly determines the position of the travel limit stops, then measures and records the parameters for both the open and closed positions. The settings are then stored. Unique to the industry, the Series 6A delivers online Adaptive Control. During operation, the unit continually optimizes control parameters and travel times in response to changes in line pressure. The benefits are control efficiency, reduced maintenance, increased service life and lower operating costs. Bray’s Series 6A corrective maintenance and preventative maintenance self-diagnostics run constantly. Corrective diagnostics aid in finding the cause of a problem. Preventive diagnostics reduce costs by identifying potential problems as they occur. The results are indicated both via a PC connection and on the local LCD display. All diagnostic data can be continually monitored and recorded. Additional standard features include valve position manual override, an internal air supply monitor, a high visibility local position indicator and a locking device that prevents adjustment shifts due to line vibration. Internal flow restrictors offer precise control of even the smallest of pneumatic actuators. Optional accessories include an external gauge manifold with up to three gauges, volume boosters and an air filter regulator. Optional boards include a retransmission module, programmable electronic switches and cam activated limit switches. All optional accessories and boards can be easily installed in the field. • High tempera • 4~20 mA DC (Note. 1) • Input Signal • 235 15 • Input Resistance • Max. 7.0 bar (100 psi) free of oil, water, and moisture • Air Supply • 60~100 (Note. 2) • Operating Angle • Pneumatic Connections • Rc 1/4 or NPT 1/4 • Electrical Connections • Rc 1/4 or NPT 1/4 • Ambient Temperature • G 1/2 or NPT 1/2 • Pressure Gauge • Ex md B T6, Ex md C(H2) T6, IP66, Ex ia B T6 • Output Characteristics • Linear • Linearity • Within 0.5 % F.S • Sensitivity • Within 1.0 % F.S • Hysteresis • Within 0.5 % F.S • Repeatability • 5 LPM (Sup. 1.4 kgf/ ) • Air Consumption • 80 LPM (Sup. 1.4 kgf/ ) • Weight • 3.5 kg (with terminal box) • 3.2 kg (without terminal box) • Protection Class