ERJ staff report (PR)
London – Wireless technology has become a growing feature of many operations in the rubber manufacturing and related raw materials and chemicals industries – transmitting information, of varying degrees of criticality, from devices located in production, process and handling/storage facilities.
These capabilities, though, are now under threat from a harmonised standard written by the European Telecommunications Standard Institute (ETSI), which is recognised as an official European standards organisation by the European Union.
Written with the intention of preserving bandwidth, the EN 300 328 V1.8.1 standard amends the existing rules for all devices using the publicly available radio band. The band includes millions of industrial devices using WiFi, Bluetooth and Zigbee technologies and comes into force on 1 January 2015.
The harmonised EN standard covers the requirements of article 3.2 of the R&TTE Directive, which states that “in addition, radio equipment shall be so constructed that it effectively uses the spectrum allocated to terrestrial/space radio communication and orbital resources so as to avoid harmful interference.”
As written, though, the standard will have a major impact on manufacturers as it does not allow industrial wireless control systems to function, warns GAMBICA, a UK trade body for instrumentation, control, automation and laboratory technology industries.
The standard introduces the concept of ‘listen before talk’ (LBT), which requires each radio device to first check whether another device is transmitting, holding back until the channel is free, explains Andrew Evans, technical executive at GAMBICA. This, he said, will cause random and unpredictable communication delays.
“The entire idea is simply non-viable,” commented Evans. “At times of heavy use, the result is 'graceful degradation of service'. Unfortunately, the real problem for an industrial site is that key wireless devices can never be relied upon to report their alarm or status messages in a timely fashion.”
Industry, said Evans, has tried to work with ETSI by submitting comments on the revision of EN300328 V1.8.1. This has included suggestions for exemption or optional use of LBT within defined industrial automation areas. These solutions, though, have not been included in the new revision of the standard.
Industry has also worked to develop an IEC standard: 62657-2 (2013) “Industrial Communication Networks – Wireless Communication Networks – Pt 2: Coexistence Management”. But the harmonisation of this standard under the R&TTE directive has been blocked by ETSI.
GAMBICA is now urging all member companies providing industrial wireless equipment, or whose services rely on these systems, to contact their UK trade association or other organisations on the continent. The industry, it said needs to explain the possible consequences of LBT to the European Commission and call for the harmonisation of EN62657-2 under the R&TTE directive as soon as possible.
“Wireless process control technology is a significant growth area which provides major cost savings in wiring and installation time,” concluded GAMBICA. “Many sites in the UK have wireless systems installed and more are in the pipeline. At a stroke, these investments are put at risk and the future growth of UK based industry will be gravely harmed.”