Keyword Search
 

 

Home

Search Proceedings

About NCSL

Contact Us

Help

View Paper

Session Topic: 2C, Pressure Session

   

Paper Title: A Force Balanced Piston Gauge for Very Low Gauge and Absolute Pressure

   

Date & Time: MONDAY, August 5, 2002

 

2:30pm - 4:00pm PARALLEL SESSIONS - SESSION 2

   

Speaker: Martin Girard DH Instruments, Inc.

Email: MGirard@dhinstruments.com

   

A new piston gauge covers the range of gauge and absolute pressure from less than 10 Pa to 15 kPa. The instrument uses a mass comparator to measure the force resulting from differential pressure across a piston in a close fitting cylinder. Independent high and low pressure chambers allow true differential operation. In absolute mode, reference vacuum of less than 0.05 Pa is maintained. A novel piston centering system avoids rotation of the piston by using the flow of an independent pressure through a micron size, conical piston-cylinder gap to center the piston in the cylinder without rotation. The instrument is calibrated fundamentally in terms of mass and piston-cylinder effective area. Estimated measurement uncertainty is ± (20 mPa + 3•10-5p). An automated pressure controller is included. Software allows multi-point comparisons with another device to be run unattended. The system has been used to test capacitance diaphragm gauges and other devices in a variety of ranges in both differential and absolute modes.

NCSL International © 1996-2002 All Content.
1800 30th Street, Suite 305, Boulder, Colorado 80301-1026
Tel: (303) 440-3339 Fax: (303) 440-3384
info@ncsli.org

CD-ROM produced by X-CD Business Solutions