Windowless rooms with three-foot thick cement walls.
Dark basements that have never known heating or air conditioning.
Windswept rooftops that no WiFi can reach.
Internet dead zones can happen above, below, and in the middle of facilities of any size, location, or age.
Often, the places with the least amount of internet connectivity are the best spots for critical building mechanicals, like water pumps, electrical closets, and elevator systems. Automating data collection or remotely monitoring these assets can be especially challenging.
Welcome to The Dead Zone
Connectivity challenges occur more often in old buildings. This makes sense considering that half of the commercial buildings in the US were built before 1980. However, newer buildings are not necessarily immune to these issues either. The systems in recently built structures are still usually tucked away, out of sight, and beyond the reach of WiFi networks.
Moreover, factories of any age also face similar issues. While production lines, air compressors, tanks, and machines are generally out in the open on the factory floor, the sheer size and amount of metal present can be a big hurdle for wireless signals.
So what does this mean for your factory, building, or facility? What’s the point of the Industrial Internet of Things if you can’t even get a basic connection to the assets you want to monitor, automate, or control?
Don’t worry– there is a solution. In fact, there are multiple ways to address connectivity. The key is asking the right questions to figure out the best solution for your facility.
In this post, I’ll walk you though how we think about these problems at Temboo, so you can learn from our customers’ lessons and be a step ahead on your path to implementing IIoT.
First, what are you actually going to use the internet for?
I know this sounds like a simple question, but really think about it. Be specific!
Do you need a large volume of data transmitting over the internet in real time? Something along these lines could be a live video feed or streaming lots of complex sensor data at low latency to the cloud.
Or maybe you only need an email or SMS alert when something clearly goes wrong. How important is historical data to your business and how often will you really need to access it? I always ask customers about this because it can save them a lot in terms of complexity and cost.
Often our customers ask for real time data at first, but when we dig a little deeper, we learn that they really just need data every few minutes or hours or days. Or even if they do need data at the level of seconds, they don’t need it in real time.
In cases like these I recommend setting up a system where critical alerts can be delivered immediately, but all the sensor and machine data within normal ranges are uploaded intermittently in batches.
Here are some examples:
• For an indoor hydroponic farm that needs temperature, light, and nutrient solution monitoring, we’re scheduling data readings to be uploaded every fifteen minutes because they want more data than they’re currently getting from their once-a-day manual inspection but would be unnecessarily overwhelmed with data every second or minute. This makes sense if you think about how fast plants respond to environmental changes.
• At a massive old building complex we’re helping the building manager track freight elevator usage. Their system is set to log whenever an elevator changes what floor it’s on, and then a day’s worth of floor data is uploaded every 24 hours. This makes sense because the customer cares most about trends in elevator usage over time and already has a robust system in place for learning about immediate elevator issues (namely, the alarm button and tenants complaining).
Why does the amount and frequency of data matter?
These questions are important because they allow you to narrow down what kind of internet access is really needed for your application.
For example, there’s a big difference between internet connections that can support live two-way video conferencing and those that only need to receive and upload a few data packets occasionally.
In the former the connection has to be high-bandwidth and always available, whereas in the latter low band-width and intermittent availability is acceptable because even if a packet fails to transmit, the system can send it again moments later.
Once you know what kind of internet connection will work for your application you’ll be better equipped to explore all the ways of bringing connectivity to hard to reach locations. The key is understanding that the internet connection you use for asset monitoring and IIoT applications doesn’t necessarily need to be as robust and high-bandwidth as one you would need for computers in a modern office.
OK, so now that you know how much internet you need, let’s figure out how to get it.
Try WiFi (Obviously)
I know I’ve spent a lot of time explaining all sorts of situations where WiFi doesn’t work, but please hear me out!
Now, I realize that some factories have concerns about wireless signals affecting their machines’ operations, and some places just don’t have WiFi at all (like a storage basement I visited last month). However, if neither of those is the case, you should see if WiFi can work.
You might have ruled WiFi out because the network is slow or inconsistent in the area where you need to install your sensors or connect your asset. But recall the type of connectivity your application really needs.
If it’s only sending a low volume of data intermittently, that not great WiFi reception might actually be just fine.
Plus, it’s often simple to add another WiFi router or extender to bring the network where you need it.
Don’t forget Ethernet
When WiFi won’t work, I usually recommend looking at Ethernet next.
Every place with internet access has, at a minimum, Ethernet ports on their routers. And more places than you think have Ethernet ports installed at various points around the building.
Even if there are no Ethernet ports where you’d like them, you can use a wireless bridge like this one to ‘catch’ a WiFi signal and make it available over Ethernet.
Ethernet cords are inexpensive, and because they are physical wires, you can direct them to exactly where you need connectivity and navigate them under, over, or around any obstruction like a wall.
There are two important things to keep in mind when dealing with Ethernet:
- The maximum length an Ethernet cord can typically carry a signal is 100 meters.
- Where you put the cord is important to consider carefully. You’ll want to make sure it doesn’t get in the way or accidentally unplugged, so taping it down along the floors and walls or running it overhead are good ideas.
Cellular: More expensive but sometimes easier
If WiFi has already been ruled out, you might think using a cellular data network for connectivity is off the table too. And while that’s true in many cases, there are still times when you should consider it as an option.
Cellular is definitely not going to be a good fit in a basement or interior room where your phone doesn’t work and you can’t get WiFi to come through. However, you should consider it if the things you want to connect or monitor are too remote for WiFi or Ethernet but are in areas that still receive a cell signal.
Some examples of this type of location are elevator control rooms, water and propane tanks, storage buildings, outbuildings, garages, and more. Equipment and spaces that are on roofs, outside, or beyond the main public areas of a building or campus are all good examples of places where cell signals will still be strong, despite the lack of WiFi.
It’s previously never made sense to connect these spaces because no one has really been doing work on a computer there. But with the rise of IoT technologies and remote sensor monitoring, there’s something to be gained by bringing internet connectivity to these spots.
Rather than convincing the IT department to install an Ethernet port or WiFi router in these places, it’s often going to be a lot faster, easier, and cheaper to get a basic portable WiFi hotspot from a cellular provider to deliver internet to the area. Cellular companies are increasingly catching on to this and are offering low-volume data plans to support these use cases.
Another useful feature of portable WiFi hotspots is that they create a new internet network that is completely separate from the main one at your building or facility. This can help mitigate security concerns that your IT department might have regarding unfamiliar physical devices and connected sensors being on the same network as all of their other computer systems.
I’ve often seen WiFi hotspots used in places where a fully separate network was desired for connecting physical assets out of security concerns, despite the existing WiFi or Ethernet network being available and close at hand.
What else? Mix & Match & More
So what do you do if you still can’t find a way to get connectivity where you need it? For example, the water pumps you want to collect data from are in the basement, behind walls too thick for WiFi or cellular and situated more than 100 meters from the nearest place you could plug in an Ethernet cord.
Consider these options:
Call your cable company or ISP
Your local internet service provider knows where all their cables are, and they have an incentive to make the most of the networks they’ve already installed. By talking to them, you might find that there’s already an existing broadband line or internet connection close to where you need it (even in a basement).
In the best case they might be able to activate an unused and unknown to you internet connection point. Keep in mind that an older technology like DSL may provide enough data for your particular application, and ask about it! Their sales representatives or technicians may be so used to only selling and installing broadband and high-speed internet access these days that they might not offer other options unless prompted.
Combine cellular, WiFi, and/or Ethernet together
Here’s an example to demonstrate how this can work:
I want to install some connected temperature sensors in the boiler room of my office building. The boiler room is surrounded by thick cement walls that block wireless signals; the basement can receive WiFi signals but doesn’t get any cellular reception; and my building manager won’t let me add any devices to the building’s existing network. To resolve this, I put a cellular WiFi hotspot on the first floor of the building where it can get reception. In the basement outside the boiler room I place a wireless bridge that can catch the WiFi signal from the hotspot upstairs and convert it into an Ethernet connection. Finally, I arrange the Ethernet cord so that it travels from the bridge and then into the boiler room under the door.
Voila! I’ve combined these three methods to be able to collect data from the boiler.
Try powerline Ethernet
If you’re still having problems, powerline Ethernet may be able to help you close the connectivity gap. This technology allows an internet signal to be transmitted through the wiring in the building from one power outlet to another. TP-Link offers a range of options for this.
The wiring of your building and, particularly, the distance the signal needs to travel from one power outlet to another will determine whether this a viable solution. Unless you have intricate knowledge of your location’s wiring, you’ll simply need to test this on location to see which pairs of outlets you can get the signal to travel between.
Connecting the Dots About Connectivity
There’s a lot more that can be said about connectivity and a long list of other methods that can be explored (LoRa, Sub-1 GHz, Zigbee, Bluetooth Mesh, etc.). My aim here has been to focus on the most widespread, familiar, and practical methods at your disposal today.
This is the advice I give to our customers that actually enables them to resolve most connectivity issues themselves, using common hardware that they can easily acquire from a variety of sources.
We take the same approach for every step of building Industrial IoT systems with our Kosmos IoT Platform, enabling our customers to employ connected sensors and actuators in their products, processes, and facilities using the most widely applicable and easy-to-implement technologies.
If you haven’t already, sign up for Kosmos today.