Speak to any electrical engineer, auditor or inspector who has been involved in the procurement of hazardous area electrical systems from overseas vendors and you will hear the same story repeated on multiple occasions:
“When it got to site we had to replace 20% of the glands and cable”
“The wiring doesn’t comply with AS/NZS 3000”
“They didn’t follow the tender documents, we listed all the Australian standards”
These are just some of the many phrases uttered by members of the electrical discipline in Australia when reviewing the purchased equipment from international vendors. So, the question is why does this keep happening? As with all of these issues there are multiple contributing factors but for the purpose of this Blog we will just focus on a few.
Australia’s use of IECEx Standards?
Many overseas manufacturers of hazardous area systems know that Australia accepts the use of hazardous area electrical equipment holding an IECEx certificate. This piece of information is sometimes misinterpreted as meaning that Australia uses the IECEx standards. Whilst Australia is an active and full member of the IEC Technical Committee TC 31 responsible for the preparation and maintenance of the IECEx international standards relating to equipment for use where explosive atmospheres exist, we do not directly adopt these IEC standards for use in Australia. The original IEC documents are adopted and then modified to take into account Australian/New Zealand conditions, and this is the first area where problems are introduced. Overseas suppliers fail to understand these differences, some of which can have a significant impact on the compliance of the packages and skids sent to Australia.
AS/NZS 3000 “The Australian Wiring Rules”:
There really can be no discussion about the compliance of electrical wiring in fixed electrical installations in Australia without knowledge of AS/NZS 3000. Fixed electrical installations in Australia are governed by the Australian Wiring Rules AS/NZS 3000. This standard has been developed by Standards Australia and industry experts and is applied on a mandatory basis in accordance with various State legislation. AS/NZS 3000s history is tied to an Australian standard AS CC1.1, because this is an Australian standard and is not an adopted international standard there are many significant differences to other international standards for electrical compliance of installations such as IEC 60364. Failing to understand the critical role AS/NZS 3000 plays in electrical compliance in Australia is one of the leading causes of compliance issues for overseas supplied equipment. Ignoring AS/NZS 3000 during the design phase is almost certainly going to lead to significant reworks when the packages arrive in Australia.
Voltage Drop, Cable Sizing and Cable Construction:
Sourcing suitably constructed cables and then sizing conductors correctly can be another compliance issue faced by international suppliers of hazardous area electrical packages to the Australian market. Cables constructed to international specifications and standards may not meet the requirement of Australians standards for cable construction and testing such as AS/NZS 5000.1, AS/NZS 5000.2, AS/NZS 1429.1 and AS/NZS 1429.2. These problems can be further compounded by failing to size cables and subsequently the circuit protective devices correctly taking into account the calculated voltage drop and impedance on the relevant cable fault loops. Without knowledge of AS/NZS 3008 and AS/NZS 3000 errors will likely be made.
Documentation: The Australian hazardous area industry has strict quality and compliance\controls, it is important that all packages that are designed and built for the Australian market have the appropriate documentation to demonstrate compliance. Strict documentation requirements will be required in site specifications and in a great many cases this documentation is required in order to be “deemed to comply” with certain Australian standards. Some common items that have proven to be issues on previous major projects include:
- Hazardous area verification dossiers not complying with AS/NZS 60079.14,
- Hazardous area ITRs not compliant with AS/NZS 60079.14 and AS/NZS 60079.17,
- Cable and circuit validation results not complying with AS/NZS 3000,
- Incomplete documentation demonstrating compliance of the Functional Safety of the
Safety Instrumented Systems, - Conformity Assessment Documents not meeting the requirements detailed in
AS/NZS 60079.14, - I.S Calculations, Purge and Ventilation calculations not being completed.
The issues discussed above are just some of the issues faced by international suppliers of electrical packages as they relate to the application of Australian standards. It is a huge undertaking to attempt to understand the compliance framework of electrical equipment and packages for use in Australia and it is unlikely the problem can be solved with a few short training courses. Engaging subject matter experts earlier on in the project life cycle, who have a detailed understanding on how to navigate, interpret and apply Australian standards is one of the few options available to ensure packages have the required engineering and design oversite.