There are many good reasons to switch to wireless for your sensor requirements. It almost seems an easier question to ask ‘why not?’ but I’ll start with ‘why?’
The first, most obvious plus for wireless is the lack of wires! With moving loads, trying to keep the cables neat, tidy and unbroken can be a pain. Depending on the installation, replacing damaged cables can be very tricky, time consuming and expensive. Fault finding on complex systems can also be very time consuming.
With a wireless system the initial installation process can be very quick and easy. Wireless sensors can be moved to different places if continuous monitoring is not required, saving costs.
All our transmitter modules can run on batteries, also removing the need for power cabling. Depending on sample time and frequency battery life of up to 5 years is achievable.
Devices can be easily swapped out if required. It is even possible to change the data tag of the new device to match the one being removed so none of the receivers need to be changed.
Extra devices can be easily added to the system. Only requiring simple reconfiguration of receiver devices.
Wireless Issues and How We Address Them
People often worry about the security of their data. When sending data wirelessly anyone with the correct receiver could also be picking up all the data. Fortunately we have a way around this with Group Keys. Once a Group Key is set, only devices using the same Group Key can ‘see’ the data from that device. (The Group Key offers millions of different combinations).
Another concern can be about interference from other devices. Firstly, due to the T24 error checking, if data is being displayed, it will be the correct data. There is a possibility that other radio traffic could interfere with T24 transmissions and we therefore provide within our Toolkit a spectrum analyser to check radio traffic on the 2.4GHz frequency band. If heavy traffic is discovered simply switch to a less congested channel.
Before installing any system it is important to test that it is correct for your uses. Our T24 Toolkit allows for monitoring of radio signal levels at both the device and the base station to allow full analysis of variation with movement and other environmental factors.
For our testing we use an open field site with the transmitter 3 m above ground and the receiver at 1.5 m above ground. Increasing either height will generally increase the range. Any obstacles within range will affect how the radio propagates and will change the range and coverage.
It is also worth noting that the positioning of the components that make up any wireless telemetry system always involves a degree of experimentation. Time spent on this aspect will always ensure a successful outcome.
By Tom Lilly, Technical Support Operator at Mantracourt