Industrial communication network infrastructure options are diverse and usually complex. When they aren’t as reliable as they need to be, the process results in unplanned downtime or worse. Most problems result from the components selected, installation practices or design. However, with a solid architecture plan, the system will perform as intended.
The challenge is that industrial networks aren’t built from the ground up. A company’s network is usually developed in steps that grow with the life of the plant. Plant expansions, relocations, technology updates and remediation are the main reasons for changing a network infrastructure. Rather than building the network from the ground up, the goal is usually strategic. To bridge the manufacturing and corporate networks, strengthen reliability and security or to adopt predictive maintenance practices that require remote monitoring of asset conditions.
Ethernet and Wireless
Open network protocols for industries, like ControlNet and Modbus have been losing popularity to Ethernet connections. Ethernet connections are much more stable and has better speed, bandwidth, flexibility and communication management than the earlier protocols. Assembly lines and warehouse picking lines are often some of the first areas to be connected by Ethernet. “Some areas of a network will remain on a ControlNet-like infrastructure, with its islands of information and slower data rates, when the equipment doesn’t allow for Ethernet connectivity or it’s cost-effective to change,” says Mara White, marketing manager at Fluke Networks.
Networks also usually remain wired where high speed or safety is critical, but other hardwired applications are being replaced by wireless alternatives using Ethernet bridges, WiFi or cellular networks. Process I/O used in alarming, alerting and condition monitoring is increasingly changing over to wireless.
Changing over from wired to wireless is a selective process. “As the installation cost to wire becomes prohibitive or the capacity to install additional fiber or cables is insufficient, wireless becomes a viable alternative for these functions,” explains Michael Martinez from Invensys Operations Management’s Critical Infrastructure and Security Practice. “Once a wireless infrastructure is in place, incremental wireless solutions often follow,” adds Hesh Kagan, director of technology innovation for Invensys. “For instance, real-time location systems are very inexpensive to add on and deliver a large return on investment.”