Device integrates gas flow control functions with mass flowmeter

Simplifies basic flow control installations and helps network multiple instruments.


The Compod from Sierra Instruments serves as a programmable control module working with mass flow meters to create gas flow control systems.

The company says that with its advanced capabilities, coupling the Compod with Smart-Trak mass flowmeters and controllers greatly simplifies basic flow control installations and permits networking of multiple instruments using open-source Modbus RTU protocol. With two digital outputs and one analog input, the Compod can be configured by the end user for a wide variety of process controls including:

  • Gas mixing and blending;

  • Gas ratio control;

  • Simple batch processes;

  • Triggering alarms;

  • Starting or stopping gas flows automatically under user-defined conditions; and

  • Gas flow totalization.

Compod also monitors the functionality of the mass flowmeter or controller and includes diagnostics, notifying users of faults or system updates.

The Compod mounts to any Sierra Smart-Trak 100 Series unit, converting the instrument’s internal RS-232 communications into multi-drop RS-485/Modbus RTU. With Modbus, multiple instruments can be daisy-chained over a single network. When used with a PLC or master computer, each instrument equipped with Compod becomes a node capable of sending and receiving data and commands.

Users can use Sierra’s provided software or write proprietary software using open-source Modbus protocol to configure standard functions for the Smart-Trak 100 Series. Compod’s two digital input/output channels and the analog input channel and a configurable pulse output channel can automate gas processes without the need for an external PLC or computer.

—Edited by Peter Welander, process industries editor,
Process & Advanced Control Monthly eNewsletter
Register here to select your choice of free eNewsletters.

No comments
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2013 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
A cool solution: Collaboration, chemistry leads to foundry coat product development; See the 2015 Product of the Year Finalists
Raising the standard: What's new with NFPA 70E; A global view of manufacturing; Maintenance data; Fit bearings properly
Sister act: Building on their father's legacy, a new generation moves Bales Metal Surface Solutions forward; Meet the 2015 Engineering Leaders Under 40
Cyber security cost-efficient for industrial control systems; Extracting full value from operational data; Managing cyber security risks
Drilling for Big Data: Managing the flow of information; Big data drilldown series: Challenge and opportunity; OT to IT: Creating a circle of improvement; Industry loses best workers, again
Pipeline vulnerabilities? Securing hydrocarbon transit; Predictive analytics hit the mainstream; Dirty pipelines decrease flow, production—pig your line; Ensuring pipeline physical and cyber security
Upgrading secondary control systems; Keeping enclosures conditioned; Diagnostics increase equipment uptime; Mechatronics simplifies machine design
Designing positive-energy buildings; Ensuring power quality; Complying with NFPA 110; Minimizing arc flash hazards
Building high availability into industrial computers; Of key metrics and myth busting; The truth about five common VFD myths

Annual Salary Survey

After almost a decade of uncertainty, the confidence of plant floor managers is soaring. Even with a number of challenges and while implementing new technologies, there is a renewed sense of optimism among plant managers about their business and their future.

The respondents to the 2014 Plant Engineering Salary Survey come from throughout the U.S. and serve a variety of industries, but they are uniform in their optimism about manufacturing. This year’s survey found 79% consider manufacturing a secure career. That’s up from 75% in 2013 and significantly higher than the 63% figure when Plant Engineering first started asking that question a decade ago.

Read more: 2014 Salary Survey: Confidence rises amid the challenges

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.