No strings attached: wireless industry

Industrial networks are changing shape as wireless steals a march on traditional Ethernet.

But it hasn’t always been that way.

Corporations concerned with security and stability have, until recently, been fairly shy about abandoning the safe haven of the wired world.

Honeywell, which launched its first industrial wireless product back in 2003, has witnessed this shift in perception first-hand.

The company’s first wireless offering was a point-to-point communication link between a sensor and gateway, says Diederik Mols, industrial wireless business leader at Honeywell Process Solutions.

“It got some interest right away and quite a few deployments, but there were a few issues with frequency and availability.”

Then in 2007 the company launched a new wireless concept called ‘One Wireless’.

One of the key improvements was the development of a mesh network that enabled communication between multiple access points and devices at the same time, without interruption.

Mols says this offered redundancy similar to a mobile phone, “allowing users to roam from one access point to another without losing their connection”.

By 2009, Mols says some early adopters had emerged, but most companies still wanted further assurances over its security.

That fear has now completely gone, says Mols.

“Today’s users are far more wireless-savvy owing to the proliferation of wireless devices on the market,” he says.

From small deployments of maybe 20 wireless I/O points, he says these have risen to 2,000 points, “and no doubt it will go beyond this.”

One example is steam trap monitoring devices, which in a typical plant can number up to 5,000.

“It was not economical to think about wiring this type of application but with wireless it is easy to do,” says Mols.

Other popular applications are emerging for safety – with personal gas detectors that will notify the control room when activated, “which can mean the difference between life and death”.

One of the most compelling factors supporting wireless technology is its comparatively low cost.

“When it comes to choosing wireless technology for a brown or greenfield project, typically you can save about 50% on any project compared with when it is fully wired,” he says.

“It also speeds deployment, whereas if you have to wire, it can take weeks, if not months.When the network is wireless, you can usually complete it in a few days.”

Emerson Process Management has also been involved with wireless infrastructure for many years.

In 2007 it released an open WirelessHart protocol called Smart Wireless, and from there, has developed wireless versions of traditionally wired equipment including temperature and level sensing instruments.

“We now have wireless versions of equipment that we don’t even offer as wired,” says Danny Vandeput, wireless business leader at Emerson Process Management.

Emerson offers field wireless solutions focused on monitoring and control of remote assets, and plant-wide wireless which is similar to a hotspot in an airport, and used for people tracking or mobile workers, says Vandeput.

“In the past staff would have had to contact operators with a walkie talkie. These days we have mobile workers who can perform maintenance tasks such as calibration, or testing an ‘open and close’ valve, without even involving operations.” And because it can tolerate a much higher data rate, users can even have wireless for high bandwidth applications such as video applications for asset tracking, he says.

Wireless technology can also offer a neat solution to tightening emission and safety regulations.

“Many brownfield plants have to comply with the new regulations. This means they may need to install sensors, and suddenly WirelessHart is an interesting product,” says Vandeput.

He cites the example of a refinery that uses pressure relief valves to ‘flare off’ as a safety response to a sudden buildup of pressure.

“Now you can have a wireless acoustic or pressure transmitter added to a pressure relief valve so from the moment it gets activated, the operator is alerted that there is a flaring situation,” he says.

For greenfield sites, he says wireless networks also enable very quick commissioning, and are typically 40 to 60% cheaper than a wired solution.

“Cabinets and the running of cables – these all disappear,” he says.

When it comes to reliability, however, it is still wired networks that operators turn to for mission critical situations.

However, there are some early signs that even this might be changing.

“In the industrial communications arena it is very important to have reliable communications to offer reliability, safety and security,” says Ewald Kuk, a vice president for industrial communication at Siemens.

This focus on security extends to provision of wireless networks, and Siemens has built its offerings around the wireless broadband WiMAX standard.

“Unlike relatively unstable wireless networks, WiMAX can be deployed as a private network infrastructure and is owned by the customer,” says Kuk.

The key benefit of this is to ensure reliability.

“For example, if you have a blackout in an electrical network, it’s very important you can still maintain communication. With our private wireless network…you have a stable network no matter what happens in a provider network.”

As a vote of confidence in its wireless reliability, Siemens also claims to be the only company in the world with a wireless safety solution.

“An example is the need for an emergency shutdown – which is very important in process safety control to enable,” says Kuk.

Run over a wireless communication network called Industrial WLAN, this can offer some advantages over a wired solution where there is a “maintenance commitment where you must check or change the cable,” he says.

But it is still early days for mission critical wireless infrastructure.

“While the arguments for wireless networks are growing, before it replaces wireless across the plant, we need to find a solution for really low power use,” warns Kuk.

“Wherever you have wireless access points, you will need power. We are still a long way from bringing this to every device.”