Wireless

Are you the right fit for wireless technology?

Do you have the knowledge and perspective to take advantage of wireless?

By Jim Montague

It's now a question of when, not if, wireless is coming to many process applications. However, that doesn't mean the brains of many process engineers and operators are ready to accept and use it.

So do you have the knowledge and perspective to take advantage of wireless?

Justin Shade, wireless product marketing specialist at Phoenix Contact, always has plenty of good advice on how to think about approaching a wireless project, how to perform a wireless audit or assessment, and how to make wireless secure.

"The biggest thing users need to consider is their expectations of a wireless network," says Shade. "Wireless products are becoming faster and more reliable, but many users expect them to function like standard wire. This isn't the case. There's always going to be a latency factor in a wireless system that's not in a wire. This is a fundamental point that must be designed around. If this is discussed during the design stage, then it's typically not an issue.

"Problems arise when latency isn't considered, and then causes difficulties when trying to start the system. Wireless manufacturers typically guide users on what to expect regarding latency. Engineers designing the system need to determine if that latency is acceptable for the specific application. Typically, these latencies aren't very large, but they need to be discussed when implementing a wireless system."

Shade explains that the main thing to know about wireless is that there isn't one technology or one device that will fit every application a user may need. "There are products built for high-bandwidth applications, low-bandwidth applications, single-user connections, multi-user connections, point-to-point, multi-point-to-point, etc.," says Shade. "If you're not familiar with what's available, the best place to start would be to discuss your applications with a manufacturer's salesperson, wireless system integrator or wireless value-added reseller. These contacts can help walk you through available products, show how they function, and help decide on the best option for your application. During these conversations, you can also discuss system design, pre-installation services and classes the manufacturer provides to help make sure your installation goes smoothly."

Since all wireless installs are different, it's never a bad idea to do a pre-installation wireless audit.

Shade adds that wireless site assessments are still crucial. "Since all wireless installs are different, it's never a bad idea to do a pre-installation wireless audit," adds Shade. "Depending on the wireless technology used and the environment it's being installed in, a wireless audit may or may not be required. Wireless technologies in the lower frequencies, such as 900-MHz frequency-hopping, spread-spectrum (FHSS), typically are robust enough to handle many environments. Couple this with the 1-watt transmit power allowed by the FCC, and you have a system that can work in many industrial applications. If you look at wireless systems that use licensed frequencies, such as 900-MHz and 400-MHz direct-sequence, spread-spectrum (DSSS), these bands require a license from the FCC, but with that license you're allowed to use a higher transmit power, up to 5 watts, and you should be the only person in the area using that specific frequency, so the band should be free of interference, allowing a clear signal."

Shade concludes that most wireless products today come with some type of security option. "Whether it's the inherent security of a proprietary system like in unlicensed 900 MHz, or the standard WPA2-AES security and encryption of WLAN products, there is typically some type of security available," says Shade. "On top of that, many products are building in other levels of security. These include functions like MAC or IP address filtering, or the availability of technician-specific logins. These features give users another level of comfort that their investment is secure from outside intrusion."

See? That wasn't so painful. Just another little technological twinge to get used to.