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In 2000 and 2001 quite major changes were made to Australia’s major electrical standards. These particularly affect those relating to campervans, motorhomes and caravans, and now also their annexes.
The changes were not made on technical grounds alone. They included enforceably changing various user, and other practices that were electrically dangerous: in particular those relating to faulty and misused supply cables. Experience over decades increasingly indicated that faulty and/or misused cables were directly or indirectly responsible for a substantial number of the 100 or so deaths from electrocution that occurred in this country each year. Since the introduction of these new Standards, Australia’s death rate from electrocution has halved.
The CMCA now has no option but to ensure that the requirements of the new Standards are followed at CMCA Rallies. The Club not only has a moral and ethical obligation to do so, it has a legal Duty of Care to do so. Here are the main electrical requirements for future Rallies. These requirements will be strictly enforced. The previous ‘she’ll be right mate – it’s all common sense’ attitude of some Members towards 240-volt power simply has to cease (at least at CMCA Rallies), not least because such attitudes place innocent Members at potential risk: and the CMCA and Rally Organiser/s in a morally, ethically and legally untenable position. There are also insurance implications.
The commonly used 30-metre 15-amp cables may still be used, subject to their being inspected for compliance and safety upon entry to the Rally grounds. Some sites however are likely to be out of reach of a 30-metre cable. There, the only acceptable solution is to use a 40-metre supply cable. These are now legal but must have 4.0 sq mm conductors (licensed electricians know what that means). I understand that some of these cables will be available for purchase at major Rallies.
The previously common practice of joining supply cables end-to-end has always been potentially dangerous. It is now also illegal. The new requirement is for the supply cable to be of one unbroken length. The restriction on joining cables applies equally to the use of 10-15 amp adaptor leads. Also, totally out, is the use of double adaptors to enable more than one site to access the same socket outlet. Again, this has always been potentially dangerous. This practice too is now illegal.
The above requirements are not onerous. You are primarily required to have a safe complying cable and to use that, and only that, cable to connect your vehicle directly to the supply. If the 30-metre cable is not long enough, you must either procure a 40-metre cable from a licensed electrician– or forgo the use of site-supplied power. If you find another attendee has inserted your cable inlet plug into an added double adaptor I suggest you attempt to resolve its removal amicably – but there and then. If this fails, have the Rally Organiser remove it for you. None of the above can be negotiable. These are totally clear requirements in which ‘opinion’ and ‘interpretation’ has no relevance. The CMCA and its Rally Organiser/s will have no choice but to enforce them.
The changed supply cable rules are an inherent consequence of the ongoing change to relying on RCD (Residual Current Device) protection, where that safety device monitors imbalances in the supply to check for any leakages to earth and cuts off the current supply if that occurs. Circuit breakers also monitor for excess current flow.
For supply-side mechanisms to protect the supply cable etc (and those many vehicles that still lack RCD protection), it is necessary for the loop impedance (the total resistance to ac of the circuit affected) be within specific limits allowing also for plug and socket connections (not cable resistance/impedance alone). Loop impedance testing is not yet obligatory but the new cable specifications and requirements address at least part of the circuit (indirectly), as well as addressing other safety-related requirements. The need for enforcement is pressing. At an earlier Rally, I saw the joins of several interconnected cables lying within centimetres of pooled water. I saw one was partially in water. Also at that Rally were innumerable double adaptors (and even stacked adaptors) exposed to rain.
I am aware that some Members of the Club are retired electricians. May I respectfully suggest they do not offer advice on these matters unless they are familiar with the quite major changes in AS/NZS 3000:2000 and AS/NZS 3001:2001. The differences (and even the fundamental approach), between the previous and the present practice are extensive and profound.
For a more extensive technical, standards-related and referenced discussion of this issue please refer to my previous article published in The Wanderer. It can also be found on my own website (under ‘Electrical Cord Standards’) at www.caravanandmotorhomebooks.com
I need to disclose that, whilst I have a practical and theoretical background in the design and building of both large and small electrical and electronic equipment and systems (both prior to and subsequent to my years with GM Research), I am an engineer, not a licensed electrician.
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