Uniquely designed by Rotork Fairchild, the T6100 "Lock in Last Place" I/P pressure transducer provides flexibility, reliability, and safety in applications requiring protection from signal failures to critical control system instruments. Its simple yet effective voice coil actuation now locks in "last position" to accurately capture the setpoint, with extremely low drift after a power loss, permitting the T6100 to maintain the set point.

Operating Principles

Design of the T6100 relies on a proprietary integrated solenoid valve module interposed between the flapper-nozzle pilot and the booster section. Upon signal failure, an electrical charge stored within the active electronic circuit controlling the integrated solenoid valve module maintains the current to the voice
coil at its last setpoint. Simultaneously, a high-energy pulse closes the solenoid valve, trapping the signal pressure within the signal chamber at the last setpoint. The booster continues to provide its normal forward and exhaust flow, with the constant signal pressure now captured and maintained within the signal chamber.

The electronic circuit activates the solenoid valve immediately upon detection of a signal that falls below a base value of 3.5mA. Upon restoration of the signal, the electronic circuit sends a high-energy pulse to open the solenoid valve, restoring the pilot section's pressure control of the signal pressure to the booster as in a typical transducer. The electronic detection circuit, in series with the T6100's signal conditioning circuit, merely adds an additional voltage drop to the T6100's normal control loop. Advanced valve orifice design of the T6100 increases its forward flow capacity to a minimum of 5-scfm at 21-psfg supply pressure.