As always, picking the most appropriate and useful wireless technologies starts with determining one’s own data needs and environmental situations. This means site assessments and determining what wireless format will provide enough bandwidth, distance, power and penetration to fulfill those information and physical requirements.
“Hardwiring is still better and more reliable than wireless in many situations, but it’s limited by its flexibility and the cost of making changes. Wireless can handle more changes and let users add devices on-the-fly at less cost,” says Laurent Chalifoux, IT-OT network consultant in the Digital Industries division at Siemens. “Plus, the whole push to the Industrial Internet of Things (IIoT) is happening because users want data from everything, but that’s not a job that hardwiring can handle anymore. Users need built-in capabilities and parameters that can only be reported via wireless.”
Keep on surveying
As usual, Chalifoux advises users to start with the characteristics and needs of their own process, equipment, users and facility to decide what wireless technology to employ. He also recommends site surveys and radio frequency (RF) assessments, which Siemens offer as a service, because they’re essential for avoiding interference and gauging signal strength in individual locations.
“What do you need data from, and is Bluetooth, Wi-Fi, cellular or satellite the best choice? If you’ve got high-data cameras with real-time video from remote operations that needs to be sent worldwide, that’s much different than periodically uploading power-consumption data or other values,” explains Chalifoux. “Users can look at adding Wi-Fi without an RF assessment, but we had one warehouse customer that was experiencing a lot of interference because their lighting system was using the same channel as their Wi-Fi, but this situation wasn’t visible because it hadn’t been identified. Users can often see there’s lots of Wi-Fi activity, but they don’t know what’s causing it. This customer finally did an RF assessment, and learned their lighting system was the culprit.”
Talk, team, plan
Because wireless or any new installation likely involves different stakeholders, who may not have talked to each other, Chalifoux also suggests developing an organizational plan along with any wireless or other site assessment. “Users must determine who the owners of wireless or any new technology will be, so they can leverage them for everyone,” he says. “If the IT department is trusted with implementing wireless because they’ve deployed enterprise-level Wi-Fi, they must recognize these former installations are very different from what’s needed in manufacturing spaces. The best solution is to form a committee of OT and IT teams, give each group a chance to provide their requirements, define their different channel and use cases, and agree on who will use which ones—like an internal Federal Communications Commission (FCC).”
In fact, Chalifoux adds that many wireless users and application will benefit from the FCC defining and approving its unlicensed 6 GHz band in February 2021 in accordance with the IEEE 802.11 ax standard. The new band is already identified in some consumer products as Wi-Fi 6E. “Industrial users need to plan for how to use 6 GHz, but it should let them make fewer changes in the future,” he says.
