Connectivity is increasingly central to modern processing workflows as the trend towards digitalisation continues across the board. Many facilities have already achieved key milestones on the road towards greater interconnectivity thanks to the growing availability of high-performance Industrial Internet of Things (IIoT) devices. However, there are dangers associated with leveraging wireless infrastructures in industrial environments.
Intrinsically safe galvanic isolators are one of a suite of protection solutions designed to enable users to safely access hazardous area data, which is an extremely valuable resource for any company looking to drive efficiency and productivity without compromising safety.
RF in Hazardous Areas—Why Intrinsically Safe Isolators are Needed
Radiofrequencies (RF) cover a spectrum from radio wavelengths through to gamma rays with a generally accepted bandwidth of 9KHz to 60GHz. This is the agreed-upon area of RF as covered by explosion protection standards.
Although RF technologies have been used for decades, the introduction of IIoT devices and the rapid evolution to a digital workplace has increased the need for hazardous area wireless connectivity throughout the process industries. Now there is a growing demand for high-tech wireless devices to be routinely deployed for their many commercial benefits—even in hazardous areas where they may pose an incendiary risk.
There are maximum EIRP (Effective Isotropic Radiated Power) levels allowed in hazardous areas. This affects the deployment of hazardous area wireless devices.
To see the full safe RF limits tables, please refer to IEC 60079-0.
The first thing you need to determine is the max RF power from the radio transmitter. Standards accept the manufacturer’s technical specifications for max power as a given. You are not required to consider the likelihood that RF amplifiers could – under fault conditions – output more power than stated.
There are two key reasons for this approach. Firstly, ignition from RF alone is rare compared with ignition from electrical faults. This is because the RF of hazardous area wireless devices is not the main risk. The risk is that RF induced in plant structures can act in the same way as an antenna, with the subsequent energy having the capacity to spark at ignition-capable levels.
Secondly, the RF signals of hazardous area wireless devices can be made intrinsically safe by using an RF galvanic isolator, such as the iSOLATE501 and an explosion proof connector transit, such as the iSOLATE-CT, meaning non-Ex antennas can be used in hazardous areas.
Read more about the complexities of making safe waves for hazardous areas in our recent whitepaper.
Intrinsically Safe Isolators from Extronics
Extronics is a leading supplier of ATEX, IECEx, and North American certified wireless equipment for hazardous areas in the process industries.
The iSOLATE501 is a next-generation RF galvanic isolator designated for use in Zones 0, 1, 2/22 and mining applications. A natural progression of the iSOLATE500 (an “associated apparatus” discussed in the whitepaper), the iSOLATE501 covers an ultra-wide bandwidth plus intrinsically safe RF outputs to protect against dangerous transients.
Used in conjunction with the iSOLATE-CT explosion proof connector transit, the iSOLATE501 allows customers to use standard antennas in the hazardous area. This helps reduce the overall cost and expand the wireless options available to the end user.
If you would like to learn more about our intrinsically safe protection concept using high-performance RF galvanic isolators, contact a member of the Extronics team today.
