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SILICON SILIC CHIP www.siliconchip.com.au Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Production Manager Greg Swain, B.Sc. (Hons.) Technical Editor John Clarke, B.E.(Elec.) Technical Staff Ross Tester Jim Rowe, B.A., B.Sc Nicholas Vinen Photography Ross Tester Reader Services Ann Morris Advertising Enquiries Glyn Smith Phone (02) 9939 3295 Mobile 0431 792 293 glyn<at>siliconchip.com.au Regular Contributors Brendan Akhurst David Maddison B.App.Sc. (Hons 1), PhD, Grad.Dip.Entr.Innov. Kevin Poulter Dave Thompson SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. ACN 003 205 490. ABN 49 003 205 490. All material is copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing: Hannanprint, Warwick Farm, NSW. Distribution: Network Distribution Company. Subscription rates: $105.00 per year in Australia. For overseas rates, see our website or the subscriptions page in this issue. Editorial office: Unit 1, 234 Harbord Rd, Brookvale, NSW 2100. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9939 3295. E-mail: silicon<at>siliconchip.com.au ISSN 1030-2662 Recommended and maximum price only. 2  Silicon Chip Publisher’s Letter Electrical safety standards are not being observed Recently, I installed a number of mains-powered LED floodlights on the outside walls of my home. They were purchased from an Australian supplier but are clearly manufactured somewhere in Asia. Since they were so cheap and much cheaper if purchased in quantities of two, three or more, I purchased more than I needed for the immediate installation. In fact, one of them is featured in the Party Strobe article in this issue. I should also say that the cost of the electrician’s time in having cables run in the cavity brick walls of my home far outweighed the purchase cost of the floodlights. Nevertheless, I was generally happy with the installation. However . . . On receiving the floodlights I immediately used a multimeter to checked that the green/yellow lead in the power cable was, in fact, connected to the metalwork. I then used our Appliance Insulation Tester from the April 2015 issue to check that aspect as well. Each one passed. I then disassembled each floodlight, in order to check the state of the internal wiring. Generally, it was OK. The very short mains lead was double-sheathed, used the correct wire colours and was securely anchored with a plated metal cable gland. However, termination of the Earth lead to the metal case was definitely below standard as it was crudely soldered to the securing nut of the cable gland and then had a dollop of silicone sealant over it. If it is to meet Australian Wiring Standards (AS:NZS 60065:2012), the Earth lead should be terminated to the metalwork with a crimped eyelet connector, screw, nut and lock-washer. On the other hand, the switchmode LED current driver appeared to be safely secured on a bed of silicone sealant, effectively isolating the metal case of the driver from the metal housing of the floodlight. Also, depending on the internal construction of the LED driver, the whole thing could possibly have passed the tests for a double-insulated appliance, making the earthing of the case unnecessary. But while these floodlights have CE stickers on the outside, we doubt whether they have been subjected to any standards testing, in any country. As well, these units give the impression that they have been thrown together in a great hurry. For example, the reflectors on a couple of them had been damaged by carelessly-wielded power screwdrivers and the mounting brackets were too wide for the floodlight housings and would not allow them to be mounted squarely to the wall. The assembly workers are probably being paid an absolute pittance – which is why these units are so cheap. To solve the problem of the wonky mounting brackets I cut a section from each one of them, much to the chagrin of the electrician doing the installation. His comment about these lamps was “These are rubbish!” I had to agree with him. I should mention that these lights do produce a fair amount of electromagnetic interference and would probably wipe out AM radio reception in weak signal areas. Finally, after a month or two, all the plated screws are rusting because I live close to the beach. I will need to replace them with stainless steel screws. This episode points to the fact that we are now importing vast quantities of cheap manufactured goods, some of which does not meet Australian standards or EEC standards, for that matter. Nor is this comment confined to electrical standards – it is across the board. This represents a safety risk to the vast majority of the population, most of whom have no technical knowledge at all. Is there any obvious solution to this dilemma? Not really. We enjoy these cheap goods from all over the world and the downside is that some of this stuff simply does not meet the relevant standards. If you have technical knowledge you can take steps to check goods before you use them and/or you can also purchase from an Australian supplier, in which case our consumer laws do apply. Apart from that, it’s a case of “let the buyer beware”. Leo Simpson siliconchip.com.au