What The Heck Is Wireless HART?

Most of you are familiar with the HART Protocol, the guidelines established by the HART Communication Foundation. The protocol has been the standard for communication between the shop floor and central management software for more than three decades. The HART protocol allows digital signals to overlay analog signals and transmit information by wire to the central database and allows disparate sensors to do so over the same transmission interface.

But some manufacturers have hesitated to employ HART because of the expense of running new wires from their sensors. Enter the world of the Wireless HART Protocol, says Chuck Micallef, marketing director for the HART Communication Foundation.

"Sometimes, with all the permitting and construction costs, it could be two to six months to get rewiring done," Micallef says. "Wireless HART will save all that hassle and those costs."

Wireless HART has several advantages over traditional communication protocols because it is more secure (the information is highly encrypted), it's license-free and, most importantly, there are no wires to tie you down.

"It's a faster way to get the measurements to the central database," Micallef says. "It allows you to make faster decisions so that you can start doing predictive maintenance to your equipment rather than reactive."

Wireless HART communicates with your central control system in one of two ways. It can work where the devices communicate directly with the gateway (though it has to have a clear line of sight of around 820 feet), or it can jump from device to device in a mesh of signals and deliver it to the gateway. Either way, the information, which is communicated on a tight schedule from device to device, is 99.999% reliable, according to Micallef.

"When you have multiple pathways to the central system and a gateway that constantly adjusts to make sure the information comes in the paths of least resistance, it can be efficient," Micallef says. "It's a whole new way to think of managing shop-floor communications with your enterprise resource planning software."