At home my video recorder, hi-fi and Satellite box, have metal outer enclosure. But are supplied by a two pin IEC320 C8 connector, running back to a UK three pin plug. The earth core is simply not present in the power cord. Products are marked with the Square within a Square and the manuals state they are double insulated, not reliant on a protective earth. So your option three and pretty standard practice for such domestic goods.
If you decide to run an earth to the chassis, or follow the "product may be earthed if so desired route". Then I advise you look in EN60950 sec 2.6.2 for the requirements on Functional Earthing to ensure you are still meeting all the spacing and insulation requirements for a double insulation and SELV circuits. As usual my opinion, not that of my employers. Andrew Wood wrote: > All > I have a piece of equipment falling under the scope of EN6010. To set the > scene it is a low volume product, approx 0.5m cube, stainless steel enclosure > and will sit on a bench in food cold storage areas. Mains lead connects via > IP68 connector. > It incorporates a SMPS for universal mains operation ( current draw approx > 0.3A). > > Because of problems ensuring a reliable earth in some locations for its > predecessor, I have specifically designed it to be Class2 (double insulated). > Therefore safe for all markets. > > Now, ironically, I am encountering some "unease" with the UK sales dept. > After all everyone KNOWS that a metal box should be earthed. (I don't dismiss > this attitude lightly because it is no doubt shared by some of the customer > base.) > Technically there is no problem with providing a 3-core cable and connecting > up the earth conductor. And after all if 2 levels of protection is good, 3 > levels is better. > > Option 1 is obviously to stick with the design as is and educate > sales/customers where necessary. > > Option 2 is to provide a 3core product for the some markets and a 2core > product for others. This goes against the original intention to have a > universal product. > > Is there an option 3? ie provide 3core cable and explain in the manual that > product is designed to be safe without an earth but the earth may be fitted > if desired. What about the square in square symbol? > > I'm sure that I'm not the first to be looking at these questions. Any and all > thoughts would be appreciated. > Best regards, Andy. > > Andrew Wood > Engineer (Specials) > > Land Instruments International > England > > Please excuse following message automatically inserted by server........ > > This e-mail and its contents may be confidential, privileged and protected > by law. Access is only authorised by the intended recipient. The contents > of this e-mail may not be disclosed to, or used by, anyone other than the > intended recipient, or stored or copied in any medium. If you are not the > intended recipient, please advise the sender immediately. > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson: pstc_ad...@garretson.org > Dave Heald davehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old > messages are imported into the new server. -- Andrew Carson - Product Safety Engineer, Xyratex, UK Phone: +44 (0)23 9249 6855 Fax: +44 (0)23 9249 6014 ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
