Listen in: What are ZigBee and Bluetooth, and how can they help me?

The names are common, but do you know what they really describe?

06/19/2008


Walking the aisles of the Sensors Expo, there were many booths from companies that make wireless modules for ZigBee and Bluetooth . If you’re trying to work with wireless in an industrial environment, what should you know about these? Can they help you? ( Click here to hear comments on ZigBee from Bob Buczkiewicz, LS Research , and Pelle Svensson, connectBlue .)

The short answer is yes, but with some heavy qualification. First it will help to explain what these things are, starting with ZigBee. Stated in very simple and non-technical terms, ZigBee is a protocol that works with the IEEE 802.15.4 radio. It supports networking from device to device using several different protocols including point to point or mesh. However it isn’t complete. Using a crude analogy, think of a hamburger with a bottom bun, a patty, and top bun. The 802.15.4 radio is the bottom bun. ZigBee provides the patty. That’s most of the sandwich, but you still need the top bun, or in this case the application providing system functions. The top bun, the application layer, is is not included in the ZigBee layer, so most companies end up writing their own instructions.

Put in process instrumentation terms, that top layer is what takes information from a sensor and packages it so the infrastructure can send it to the gateway so your distributed control system (DCS) can read it. The lower layers provide the infrastructure. The problem is that if a company writes a proprietary top layer, it will only operate with other devices using the same system even if the other layers are the same. That’s why two ZigBee-enabled devices from different companies may not interoperate.

Bluetooth is similar in that it is also a hamburger patty solution and has to have the top bun. However, it has striven for a higher level of interoperability. Bluetooth has profiles, which are basically pre-configured application layers. There are many of them that cover a wide variety of applications. One common example is those odd earpieces people use with cell phones. It’s easy to mix manufacturers for those because they all use the same headset profile.

ZigBee is working on compiling profiles as well, although it is not as far along in the process. As those become more common, making interoperable devices will be much easier. Of course that assumes you want interoperability. Some companies like proprietary platforms, even to the extent of creating their own hamburger patty layer as well. For example, Emerson’s Smart Wireless platform skips ZigBee completely and has its own solution for everything above the 802.15.4 layer. WirelessHART is the same way but has offered the protocol for many companies to use, creating its own interoperable platform, a standard guided by the HART Communication Foundation .

If the whole discussion leaves you with a headache, you’re not alone. Understanding the complexities of wireless protocols and trying to create interoperability requires careful analysis. As time goes on and equipment becomes more common, hopefully the number of protocols will coalesce around the most useful, or at least the most successful.

—Peter Welander, process industries editor, PWelander@cfemedia.com ,
Process Instrumentation & Sensors Monthly
Register here and scroll down 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...
The true cost of lubrication: Three keys to consider when evaluating oils; Plant Engineering Lubrication Guide; 11 ways to protect bearing assets; Is lubrication part of your KPIs?
Contract maintenance: 5 ways to keep things humming while keeping an eye on costs; Pneumatic systems; Energy monitoring; The sixth 'S' is safety
Transport your data: Supply chain information critical to operational excellence; High-voltage faults; Portable cooling; Safety automation isn't automatic
Case Study Database

Case Study Database

Get more exposure for your case study by uploading it to the Plant Engineering case study database, where end-users can identify relevant solutions and explore what the experts are doing to effectively implement a variety of technology and productivity related projects.

These case studies provide examples of how knowledgeable solution providers have used technology, processes and people to create effective and successful implementations in real-world situations. Case studies can be completed by filling out a simple online form where you can outline the project title, abstract, and full story in 1500 words or less; upload photos, videos and a logo.

Click here to visit the Case Study Database and upload your case study.

Maintaining low data center PUE; Using eco mode in UPS systems; Commissioning electrical and power systems; Exploring dc power distribution alternatives
Synchronizing industrial Ethernet networks; Selecting protocol conversion gateways; Integrating HMIs with PLCs and PACs
Why manufacturers need to see energy in a different light: Current approaches to energy management yield quick savings, but leave plant managers searching for ways of improving on those early gains.

Annual Salary Survey

Participate in the 2013 Salary Survey

In a year when manufacturing continued to lead the economic rebound, it makes sense that plant manager bonuses rebounded. Plant Engineering’s annual Salary Survey shows both wages and bonuses rose in 2012 after a retreat the year before.

Average salary across all job titles for plant floor management rose 3.5% to $95,446, and bonus compensation jumped to $15,162, a 4.2% increase from the 2010 level and double the 2011 total, which showed a sharp drop in bonus.

2012 Salary Survey Analysis

2012 Salary Survey Results

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.