Wireless networking is a cornerstone of the “smart factory” concept, which requires the collection and transferal of data regarding the manufacturing process. While there are several types of wireless technology that can be used for manufacturing – such as 5G or Bluetooth – a common approach is industrial wireless LAN. This is what I will focus on in this article: what industrial WLANs are, and tips for monitoring them.
What is an industrial wireless LAN?
An industrial wireless LAN is similar to the WLANs found in corporate and private domains: it is based on one of the IEEE 802.11 standards (but most probably on IEEE 802.11n, ac or ax) and is compatible with wired Ethernet. However, perhaps the biggest difference in industrial environments is that networking equipment has to be rugged and more robust to handle the extreme conditions of a typical factory floor. For example, devices need to withstand very high or low temperatures, high humidity levels, constant dust, or excessive vibrations.
Another challenge is that the nature of factory floors often require specialized Wi-Fi approaches. For example: radio frequency interference and lots of large metallic surfaces mean that better radio frequency management and stronger wireless signals are required.
Incorporating wireless connectivity in a factory brings about many opportunities, but one of the biggest is the ability to connect mobile endpoints. This covers a range of applications, from giving technicians the possibility to access production data on their mobile phones or tablets, through to enabling communication with moving machine parts.
Another benefit is the ability to provide more communication possibilities for common industrial protocols like PROFINET, SafetyBridge, MODBUS TCP/IP, and others.
Monitoring industrial wireless LAN connectivity
Wireless network reliability is far more critical in industrial settings than in corporate environments, especially if process and safety controls are executed using the wireless network. In this case, even a short downtime can result in a halt in production, poor quality output, or other negative outcomes.
The latest wireless LAN standards offer features that improve efficiency and reliability of wireless signals (such as MIMO in 802.11n or OFDMA and MU-MIMO in 802.11ax); but despite this, monitoring the status of wireless connections and the supporting infrastructure is crucial. Here are three tips for getting started with monitoring your industrial wireless LAN.
1. Monitor the wireless networking devices
This includes the routers, access points, switches, and other network equipment. Many network devices offer SNMP functionality or a REST API (or both) where status information can be obtained, and this information can be used to get alerted when the hardware has failed.
Another option is to utilize the tools provided by the networking devices themselves. Many manufacturers include built-in tools that can keep you updated as to the status of the equipment. For example: Moxa, a provider of industrial wireless routers and other devices, also offers a tool that lets you monitor the wireless connections of their devices as well as changes in those connections that might be of interest.
2. Monitor the connected devices
Another good strategy to monitor the health of a wireless network is to check if the connected devices are reachable. A simple ping here can suffice: a device that does not respond to a ping might have malfunctioned, but it could also be that the wireless network has gone down.
We recently saw a great demonstration of this with our own Paessler PRTG monitoring software at a company based in Germany.
Bechtle monitors AGVs and the wireless network for STIEBEL ELTRON using PRTGThe company in question, STIEBEL ELTRON, uses automated guided vehicles (AGVs) at their production site. These AGVs are autonomous in that they receive their orders over Wi-Fi at various checkpoints. If the wireless network is down, the AGVs do not get orders and they stop – resulting in downtime and a delay in certain processes.
STIEBEL ELTRON’s IT service provider, Bechtle, indirectly monitors the wireless network by monitoring the AGVs with PRTG. PRTG regularly pings each AGV, and if an AGV is not reachable, an alert is generated. This way, admins and technicians can immediately check if the network is functioning.
A nice by-product of this process: Bechtle not only knows the status of the wireless network, but also the state of each AGV at any given time.
3. Get all your monitoring data in one place
This is more of a general monitoring best practice tip than it is specifically about wireless networks: consolidating all of your monitoring data in one tool is the best way to give you centralized dashboards and alerting. This includes having data from all your locations, from your OT environment, from your IIoT sensors, from your wired and wireless networks, and from your traditional IT devices and systems in one place.
Paessler PRTG monitoring software for OT, IIoT and IT
If you'd like to learn more about how PRTG can be used in your OT infrastructure, get in touch with one of our experts!