Smaller Process Connections – a new ½-inch diameter option on insertion probes for AdvantageMass TM100, PowerMass TM500, and BioTrak 645i/745i and 645s/745s thermal mass flow meters.
Reuse an Existing Connection – customers can reuse an existing connection and avoid the downtime of adding a new branch outlet.
New ½” Flow Body Sizes – on TM100 and TM500 inline models, available with either male NPT or ANSI 150-lb. flange end connections.
A Minimum Pipe Opening of 0.531 Inches

Everyone wants more accurate measurements for better process optimization, but reworking piping for flow meter upgrades can be costly and disruptive to production. Our new ½-inch probe gives users more flexibility in where the TM100, TM500, and BioTrak can be installed, making it easier than ever in existing facilities to take advantage of Sierra’s latest advancements in digital measurement, field diagnostics, and communication capabilities.
Greg SmithProduct Line Manager for Sierra Instruments
Sierra’s new ½-inch probe option requires a minimum pipe opening of 0.531 inches, whereas the standard ¾-inch probe diameter requires a hole size of 0.781 inches or larger. In compatible applications, customers can reuse an existing connection and avoid the downtime of adding a new branch outlet.
More Flexibility in Where the TM100, TM500 and BioTrak Can Be Installed
The optional ½-inch insertion probe is supplied standard with a ¾-inch MNPT compression fitting, or an optional ½-inch MNPT fitting. The new ½-inch probe diameter also enables new ½” flow body sizes on TM100 and TM500 inline models, available with either male NPT or ANSI 150-lb. flange end connections.
For Industrial Processing: AdvantageMass TM100 and PowerMass TM500
For industrial processing, the ½-inch probe option is available on AdvantageMass TM100 and PowerMass TM500 insertion-type flow meters.
- PowerMass TM500The TM500 features higher flow velocities up to 60,000 sfpm, AC or DC power, remote electronic options, on-board datalogging, and expanded gas programming flexibility.
- AdvantageMass TM100The TM100 is suitable for velocities up to 25,000 sfpm, with DC power input, an integral display, and standard gas programmability.
For Wastewater Treatment: BioTrak 645i/745i and 645s/745s
For wastewater treatment, the ½-inch probe option is available on BioTrak 645i/745i and BioTrak 645s/745s thermal mass flow meters. Both BioTrak product lines provide accurate measurement of air, methane, and biogas/digester gas for wastewater, landfill, cogeneration, and similar facilities to help optimize processes, reduce costs, and comply with regulatory requirements.
See the New Probe Design at WEFTEC in New Orleans
Sierra will highlight the new ½-inch insertion probe design at WEFTEC this September in New Orleans. Facilities engineers and other industrial professionals are invited to visit the Sierra booth to discuss flow meter needs, including upgrade opportunities in existing systems.
For more information, contact Sierra Instruments or visit www.sierrainstruments.com.
















