High Accuracy Resonant Pressure Sensors

Chell Instruments

home
news
search

applications
principals
products

calibration lab Service dept
Vacuum fabrications

visiting us
careers
contact

High Accuracy Resonant Pressure Sensors

Digital Pressure Module DPM

Incorporating the well proven Western Aerospace vibrating cylinder pressure transducer.

QUARTZONIX^TM Digital Pressure Standard

Incorporating a patented monolithic quartz resonator.

Intelligent QUARTZONIX^TM Digital Pressure Standard

RS-485 version of the proven high accuracy vibrating quartz beam technology with low power miniature digital electronics

Digital Pressure Module DPM PDF Data sheet download (66kB)
	*FEATURES* Ranges: 15 psia to 750 psia (115 kPa to 5000 kPa Better than ±0.01% FS Accuracy Long term stability better than ±0.01 % FS per year RS-232 or multidrop RS-485 interfaces Pressure output in choice of engineering units Up to -40 to +70 °C operating range *APPLICATIONS* Meteorological and barometric reference Low cost, high accuracy pressure standard Pressure calibration equipment Storage tank / liquid level determination
The Model 7885 Digital Pressure Module (DPM) is a completely self-contained high accuracy pressure transmitter suitable for measurement of air. The DPM incorporates the latest miniaturised version of the Weston Aerospace vibrating cylinder pressure transducer, proven in many demanding airborne and ground based applications. This sensor, being of a resonant element technology, is inherently digital in its primary signal output, and is also widely acknowledged as one of the most stable configurations, typically offering long term drift performance of around 0.005% FS per year, irrespective of its temperature exposure experience. The DPM combines this sensor with an on-board microcontroller and timer/counter circuitry. This performs all of the necessary sensor frequency and temperature compensation signal acquisition and computes pressure, delivering measurements in a choice of four engineering units. A unique feature of the DPM is that calibration and characterisation is carried out at the top level of integration. This procedure monitors the outputs over a matrix of 11 pressures at 7 different temperatures, fully characterising the device over a temperature span of up to -40 to +70 °C. Interface options include a standard RS232 port or RS-485 addressable, multidrop interface, allowing up to 31 DPMs to be networked together. Available with every DPM is a power connector and Windows^TM compatible start-up software. This software allows the user to exercise the functions of the DPM and also includes a data logger and simulation of a pressure indicator.

QUARTZONIX^TM Digital Pressure Standard PDF Data sheet download (117kB)
	*FEATURES* Ranges: 15 to 500 psia FS (105 to 3400 kPa) ±0.0001 % FS Resolution ±0.01 % FS Accuracy ±0.01 % FS / 6 month Stability Shock, Acceleration and Vibration Resistant *APPLICATIONS* Flight Testing Calibration Transfer Standards Metrology Windtunnel / Turbine Test Oceanography
QUARTZONlX^TM pressure standards are designed for use as precision pressure transducers where the highest level of traceable accuracy is required. The QUARTZONlX^TM pressure standard uses a patented monolithic quartz resonator to achieve unparalleled accuracy and stability. Pressure is measured via a change in the resonant frequency of an oscillating quartz beam by pressure induced stress. QUARTZONlX^TM pressure transducers produce an output frequency between 30 and 45 kHz and can achieve a pressure resolution of ±0.0001 % FS. The units provide conformance to a calibration curve of better than ±0.01 % FS and have long-term stability of ±0.01 % FS over a six month period. Precise thermal compensation is provided via an integrated quartz temperature sensor used to measure the operating temperature of the transducer. The low mass design of the sensing elements allow the transducer to be employed in applications which experience high acceleration, shock and vibrational loads.

Intelligent QUARTZONIX^TM Digital Pressure Standard PDF Data sheet download (122kB)
	*FEATURES* Ranges: 15 psia to 500 psia 115 kPa to 3333 kPa Better than ±0.01% FS Accuracy Long term stability better than 0.01% FS per 6 months RS-485 interface Pressure output in choice of engineering units Up to -20 to +70ºC operating range *APPLICATIONS* Meteorological and barometric reference Low cost, high accuracy pressure standard Pressure calibration equipment Storage tank/liquid level determination
The Model 970 Intelligent Quartzonix™ pressure standard incorporates proven high accuracy vibrating quartz beam technology with low power miniature digital electronics to achieve a fully compensated 0.01% FS pressure measurement. The Model 970 uses a patented monolithic quartz structure and vibrating beam to measure pressure-induced stress. The beam's frequency of vibration changes by pressure induced stress that is applied to the beam via a miniature metal bellows. The bellows isolates the quartz sensing element from the applied gas, thereby making the sensor insensitive to gas density. The Intelligent Quartzonix™ has a resolution of 0.001% FS, and drift rates of less than 0.01% FS over a 6-month period. The Model 970 uses a multi drop, 9600 baud ASCII character RS-485 type interface, allowing a network of up to 31 transducers on the same bus. The output pressure measurement is user programmable for both the pressure units and update rate. The update rate is capable of 12 readings per second. The extremely low power consumption design with a programmable sleep mode makes the Intelligent Quartzonix™ ideal for remote battery powered applications. NOTE : The Quartzonix pressure transducer is also available inside the 9032 series of intelligent pressure standards and controllers. Click here for further information.

Chell Instruments