Whether it’s Building Management Systems that gather real-time feedback on everything from humidity to CO2 levels, or cloud booking systems that use desk occupancy sensors to identify unused spaces, sensors can help bring your company’s data to life in a way that was previously impossible. It’s estimated that by the end of next year up to 50 billion objects worldwide will be connected to the internet and 50% of these will be for some type of industrial application [1].
But how do you decide which sensors to integrate with your system? This article sets out the key issues to consider when choosing which sensor technology to introduce.
[1] Quote from EEWorld’s IoT Design & Development digital e-book Sept 2019
What should I look for?
Interoperability
If you are a large company with different divisions around the world you need a solution that can work across different regions, whose component parts can speak to each other seamlessly. Not all solutions will talk to one another, as some require all components to be made by the same manufacturer. Look for systems that are manufacturer agnostic and use the most common messaging protocols, such as MQTT.
Scalability
Any solution you install needs to be future-proof. Make sure your system can be added to easily and that additional equipment can be purchased quickly and easily. It’s also a good idea to check whether new functionalities can be added to your solution without disrupting the existing system.
Cost
Finding a solution that fits your budget may be the number one goal, but a system that is cheaper to purchase initially may end up costing more than one from a more expensive manufacturer over the course of its lifetime if it needs more regular maintenance or is unreliable. System downtime and the subsequent loss of productivity could prove more costly than the initial outlay.
Wired v wireless
Increasingly, wireless is the more popular option as miniaturisation mean the demand for devices and tech to become smaller and more portable increases, but it may not always suit your needs. Key points to consider include:
- Installation – A quick, straightforward installation is one of the main benefits of wireless sensor systems. Installing wireless sensor systems doesn’t require any drilling, wiring or structural building changes. but you do need to make sure the system offers as much coverage as possible by carefully planning the placement of sensors and receivers.
- Cost – While initial costs can be slightly higher for a wireless system, any modifications you make in future will be much cheaper. If you’re planning to expand your network in the future a wireless system is far more accommodating.
- Maintenance – There are two types of wireless devices – powered and self-powered. Self-powered wireless devices harvest the energy they need to function properly. Tiny changes in movement, pressure, light, temperature or vibration are all that’s needed to power each device meaning no batteries are needed, making them virtually maintenance free.
- Flexibility and scalability – Wireless networks are easy to add to or modify. It’s also easy to scale up a wireless system over time. Wireless technology also makes it easy to take advantage of upgrades and new technologies as they become available.
Which wireless protocol?
Wireless standards, also known as protocols, are technologies used to carry a signal wirelessly. Different protocols have different ranges, data requirements, security and power demands. There are three main factors you’ll need to consider:
- How much data you need to transmit – If you’re looking to transmit larger pieces of data, such as moving pictures, or you want to network computers, you’ll need a protocol that can carry large data quantities in a short time. Most smart sensor systems only require short-term wireless transmission of small amounts of information so different protocols will be better suited.
- How many devices will be transmitting data at the same time – When too many devices in the same vicinity use the same frequency band, the radio signals can get crowded. Certain frequency bands are more widely used than others, which makes certain protocols more prone to interference.
- Which technologies and platforms you will be using: The key consideration here is compatibility. Since there are so many device manufacturers and building automation systems in use, you need to make sure the wireless protocol you select will work with the equipment you either already have or are intending to use.
The messaging protocol used
If any new equipment you buy is not talking in the same language as the software or hardware you want to integrate it with then you could run into problems. There are a number of messaging protocols available and it makes sense to pick one of the more widely used so that you can ensure interoperability and make it easier to expand or scale-up your systems in the future. Probably the two most widely-used in the IoT world are MQTT and HTTP.
MQTT’s messages can be as small as 2mb and are capped at a maximum size of 256mb, meaning it uses less data and therefore less energy than some protocols, helping to conserve battery life. It’s also useful where bandwidth is constrained. HTTP uses a larger bandwidth and can be useful for sending larger packets of data – such as documents.
Security
When choosing a smart sensor solution you need to be confident the equipment you are using complies with the highest possible security standards.
The most common method of protecting data is encryption – a random string of bits. Every encryption key is generated randomly by an algorithm, meaning it is totally unique and unpredictable. The standard encryption level for most smart sensor, IoT-connected, products is 128-bit. A 128-bit code is considered to be logically unbreakable, even using software which continually generated random sequences of bits it is believed it would take around 100 billion years to crack a 128-bit code.
Choosing a quality manufacturer
There are a number of key questions to consider when deciding which sensor manufacturer to use:
- What is the company’s heritage/reputation like? – Many IoT companies are relatively new and will be in the early phases of business development. Choosing an established company with a good track record of delivering products can help to ensure your systems are future-proof.
- How quickly can things be produced? – Choosing a reputable manufacturer who is experienced at producing high volume products can ensure lead time is minimised, whilst retaining the quality of the product.
- What testing is done? – Look for a company with a proven track record of rigorous testing, not just of their own products but who can test the software and hardware together at the earliest possible stage.
- What quality standards/accreditation have they got? – Quality is key when installing systems on a national or international scale. If things don’t work properly the impacts could be far-reaching. The best way to have confidence is to look for an international standard like ISO.
- What safety standards do they adhere to? – Look for fire retardant plastics and an internationally-recognised safety standard. Local standards may not be enough. Make sure the solution you are implementing will meet standards across all the regions you intend to use it.
If you would like to talk to Pressac about our range of smart sensors and potential integration projects please contact us.
