Saving time and money with managed wireless
Ian Loudon, International Sales and Marketing Manager at wireless telemetry specialist Omniflex, explains the benefits of using wireless technology that takes advantage of publicly available infrastructure to access your data easily, affordably and securely
Wireless telemetry systems are becoming increasingly popular in a range of industrial sectors. In highly regulated industries, such as nuclear, petrochemical or oil and gas, laying cables for data monitoring applications is not always feasible because of strict regulations and the extensive planning permissions required. Here, wireless communication systems can help facility managers retrieve and manage critical data from the field wirelessly, safely and efficiently.
Wireless communication technology is also becoming increasingly beneficial for utility providers that connect to electrical, water and gas meters and gather data for billing and control purposes. And that is not the only way utilities providers are taking advantage of wireless systems, with them also making an impact in reservoir water pump monitoring and control applications where geographical considerations and prohibitive costs rule out wired monitoring and control systems.
In these applications, it is important to work with a reliable wireless telemetry systems partner with experience of dealing with the operational challenges and infrastructure of industrial plants. This ensures that factors like antenna selection, frequency choice and system interfaces are all the best option for the job.
For example, when dealing with radio-based telemetry systems, it is important to remember that radio transmission distance and bandwidth is finite. This is based on factors such as the power of the transmitter, the sensitivity of the receiver, the type of antenna you’re using, the operational frequency and, even, weather conditions. These factors will determine whether you get a good signal or not.
It’s important that the radio transmission is efficiently managed hence the term “managed wireless or radio transmission” which ensures that your devices “share” the spectrum and are “polite” at optimising the transmission of data.
It’s important to note that in most countries around the world, to prevent interference between different users, the radio spectrum is regulated using licensed and unlicensed frequency bands. Space on licensed frequency bands is at a premium and, with more and more businesses setting up radio telemetry equipment, demand will only increase. For many plant managers, the need to pay a fee for exclusive transmission rights means operating on a licensed band is undesirable. Instead, many opt for license-free bands that are open to everyone.
However, regardless of which you’re using, the gain of your antenna cannot result in you exceeding the effective radiated power (ERP) allowed on that frequency band. On the 868 Mhz frequency, in the UK for example, the maximum ERP for short range devices and wideband devices is limited to 25 dBm with a duty cycle of 10 per cent. This puts the focus on a managed wireless protocol to use your allocation efficiently and effectively.
In other parts of the world, however, this can differ. For example, South Africa falls into the same EMEA zone and largely follows the same radio standards, although short range devices in the country must register type-approval for radio devices with the Independent Communications Authority of South Africa (ICASA). At the same time, Australia, New Zealand and Asia are considered a separate region and have their own standards. Omniflex provides approved wireless solutions into all the globally approved license free ISM bands
For example, Omniflex’s wireless modules use managed wireless techniques such as change of state operations where signals are only sent from modules to the supervisory system when there is a change that operators must be made aware of.
This is better than maintaining a constant polling signal between modules and the supervisory system that could overload the network with unnecessary traffic, or even timed updates that still involve sending unnecessary updates that compete for network traffic. Using a managed wireless system ensures that all traffic on the system is meaningful.