Re: Typing Shortcuts
Hi Bob et al. One TLA (FLA) seems to be missing, one which implies such awesome influence and power, the ultimate reason for everything., that is the SWMBO. This is the TLA that justifies all manner of actions, expenditure, or the lack thereof... It stands for 'She Who Must Be Obeyed'. No further explanation needed... :-) Chris Dupres Surrey, UK. --- 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 Healddavehe...@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: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: X ray safety interlocks.
Hi Bob. You asked: << can a low voltage relay be used to control another relay which has a set of contacts that when activated, removes the energy supply circuit to the high volatage generator? >> A couple of things wrong with that. 1. Using a 'low voltage relay tpo control' is fundementally flawed, as they can fail open or closed, and you have no indication and no 'intrinsic failsafe' operation. 2. Using a relay to 'open on energise' is fundementally flawed as the coil or associated circuits may open circuit and leave the power on, or the opening cotacts may weld together. The two independent interlocks you require are simply two mechanical 'Safety Switches', which are positively linked to the doors such that the contacts are forced apart by a cam action so that at the unsafe position the contacts are 3mm apart and are non-overidable These switches can be directly connected into the supply to the HV supply , if it's a low voltage feed and fused within the switching capacity of the Safety switches. Or the switches may be wired into a suitable Safety Relay with dual redundant series cobntacts and failure checking systems such as the PNOZ range made by Pilz, or the Minotaur range made by Guardmaster, for exactly that purpose. Take care, Chris Dupres Surrey, UK. --- 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 Healddavehe...@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: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: AC Power Primer?
Hi Brian. << Just to add a little more fuel to the flames! We supplied an Instrument to a well known semiconductor Manufacturer in Oregon which was powered from two 220 volt phases. I marked the rating plate as 220 volt one phase as has been suggested. However the local inspector made us change it to 220 volt two phase. So what is the correct definition. >> I was always encouraged to describe a supply by how many phases were not earthed, and a device by how many phases it used. In that context there is no such thing as a two phase device, at least not in the UK, as a two phase device would have three wires and the third phase is already there as the algebraic sum of the two phases. In the UK the distribution system is Earthed Neutral 3 phase equal star. In the USA and many other places there are all sorts of systems, e.g. open delta - earthed centre tap one phase, close delta earthed on phase, two phase earthed centre tap... the list is long.. In the UK, we use 1 phase and neutral, or three phases with or without neutral. Industrial systems use 2 phases, usually for control transformers which are single phase devices running at 415V, as there is no neutral. In the UK neutral and Earth are tied together at the distribution room, but NO current is permitted in the local Protective Earth conductor or the 30mA RCD's trip. I think your local inspector was probably OK in asking for the label to say Two Phase, as it was a Single phase device connected to Two phases. Sound reasonable? Chris Dupres Surrey, UK. --- 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 Healddavehe...@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: http://www.rcic.com/ click on "Virtual Conference Hall,"
Re: Decoupling Capacitors
Hi Scott, Chris et al. Your stories of decoupling caps reminded me of a delightful cost reduction exercise I was involved in. A company was making grinding machinery for Engineering, and they had instituted a fierce cost reduction exercise on the Electronics, including the Vibration Analysis board, which took signals from two G sensors for monitoring out of balance grinding wheels or bearing problems. An Engineer was allocated to the task, and he spent three months totally redesigning the board from the ground up, repacing old analogue stuff, discrete transistors etc., and replacing with Op Amps etc. And he'd carried out a full set of formal testing on the bench. I was an EMC consultant for them at the time, and they asked me if I'd like to review the new design. I did, but was unsure about his input signal levels, so I asked the Field Service guys to measure the output from the sensors in the field. I got the reply "Oh we havent fitted those for 6 years, the new bearing caps don't have accelerometers fitted". A visit to their stores found a shelf stuffed full of cardboard boxes labelled 'Returned Service stock, Vib Boards". For 6 years they'd had vibration displays in the field which stayed permanently at zero, and the customers were so pleased that the new bearings introduced 6 years previously had stopped all vibration problems. Looking back over 6 years of pre-despatch test sheets showed "N/A" in the vibration analysis section. They subsequently saved the cost of the boards, the display modules, the power supplies and all the wiring. And such is the lot of the Consultant who states the blindingly obvious, they thought I was wonderful! I suppose the moral is, sometimes cost saving exercises become TOO focused. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: EN55024
Hi Ghery. You wrote: << The law is 89/336/EEC, the EMC Directive (or as I like to call it, the EMC Professional Employment Act of 1989). It lays down, as you note, the essential requirement that a product not cause undue interference and that it operate as intended in its itended environment. No more, no less. No limits for emissions are provided in the EMC Directive. >> The Euro Directive was born of the Treat of Rome, itself born in 1972, with the express purpose of removing barriers to trade. If you read the Directive, in the first few pages I think (from memory) that it mentions 'Free trade', 'removal of barriers to trade', 'etc. etc about ten times, but in just about the whole of the document it doesn't mention Interference or crackling radios at all. The Directive is there to ensure that no Euro state can steal a lead on another by selling goods that don't have the same technical performance, i.e. that are cheaper! By doing what the Directive requires, and applying the CE mark, it simply allows the bureacrats to let the goods in without let or hindrance so that they can be traded on an equal footing with locally produced goods. Trade = peace, which isn't a bad thing... I suspect that the Euro MP's wouldn't know an EMC if it fell on their foot, but they voted it in, as it was something that could be measured and defined relatively easily and could therefore be given political force. The technical standards, CISPR etc. seem to be quite arbitary in places. For instance, the sudden cessation of conducted emissions and the equally sudden beginning or radiated emissions at 30MHz is surely a bit convenient, tho' it has to be said it is not entirely impractical. No, I reckon that the EMC Directive is not anything to do with EMC, but another tool by which the Euro Bureacrats can merge Europe into this Super State so feared by the Brits and so revered by the Galls. There, a bit of unsolicited trite bigotry, and it isn't even Friday. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: DC POWER FILTERING FOR ETS 300 132-2
Hi Chris. You asked: << What types of noise sources within a typical power supply or product would produce emissions in this frequency range? >> Sorry if this is teaching you to suck eggs... Any bridge rectifier/capacitor filter will generate Conducted EMI is that frequency range, due to the 'commutation' effects of the forward conducting period of the rectifier diodes. The higher the value of smoothing capacitor, the longer the voltage on the other side of the diode remains high, and the diode wont conduct until there is sufficient voltage (0.7V'ish) across the diode to turn it on. So, all the current to be delivered by the power supply, must be delivered to the smoothing capacitors while conducting for a very short period, sometimes as low as 100uS, or even 10uS. The average current in must equal the average current out, so if you are conducting only fo 100uS, rather than the full half cycle (10mS in the UK) then in order to maintain average output current the diode current must be 10mS/100uS x Iout = 100 Iout. So if you have a 5A power supply, the diode current will be 500A, for 100uS. A higher value of smoothing capacitor may allow only 10uS conducting time, so the current would be 5000A for 10uS. In reality these currents are rarely achieved, you simply see very hot diodes and output voltage drop. So, you have very high speed switching of very high currents just buzzing and fizzing with high frequencies. Diodes can switch very fast, and I have often measured huge amounts of conducted EMI up to 30MHz and above, though it then starts to radiate... It's a situation where the non combatant will see conducted emissions and increase the smoothing to try to remove it, when in fact that just exacerbates the situation. A simple way to reduce conducted emissions substantially is to reduce the smoothing capacitor to the point where it becomes noticeable on the target system, then double it! You may be very surpprised how 10,000uF capacitors can be reduced to a few hundred with no significant increase in ripple, but a HUGE 20-30dB reduction in conducted EMI. Difficult systems benefit from 3 phase supplies to the bridge, you can get away with no smoothing at all on non critical systems... Or using multiphase transformers etc. etc... This 'peaky' current demand of course, being as it is at the very peak of the supply voltage waveform, is the source of the problem that is the purpose of IEC1000.3.2, etc. the generation of harmonics back into the mains supply. Sorry if I missed the point of your question, but I'm a simple soul and saw what I thought was a simple and obvious cause. Or if it helps, I'm glad. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Rechargeable Batteries
Hi Mark. You asked: << why do so many battery operated equipments state that they must not be operated using rechargeable batteries? >> There is no one all-purpose reason, but the two main ones, at least the ones I worry about with battery powered stuff, are: 1. As you already implied, terminal voltage. NiCads are typically 20% lower terminal volts than Alkaline cells, and as lots of battery operated stuff needs a stabilised supply the headroom required to produce a stabilised supply can take the volts down too low. 2. Short circuit current is very high with NiCad's. If there is a fault internally, or as in one case that I had, if you drop it in water, the resulting current can destroy the PCB and associated components. Alkaline cells, ar even better, Zinc/carbon cells have a much lower short circuit cirrent and the liklihood of damage, or even fire, is reduced or even prevented completely. The short circuit thing is interesting. My son has a radio controlled car with a 7.2V NiCad battery pack. The short circuit current was enough to melt the PVC insulation on the battery wires, 1.5mm^2, and I measured it subsequently at 82Amps. You could probably start a European car with one of those! Chris Dupres Surrey UK. p.s. Anyone wrapped up a alkaline watch battery in aluminum foil? Don't! --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Overcurrent Protection: One or Both Sides?
In a message dated 06/10/00 14:34:45 GMT Daylight Time, brian_ku...@leco.com writes: << I feel that overcurrent protection should be on all current carrying conductors. With a 230V~ product you never know where in the world the product will be shipped, if the AC Main has a grounded neutral, or if the receptacle is polarized. So, I feel you never know for sure which line or if both lines will be "HOT" in reference to Earth ground. Am I being too cautious or do I have a point? >> Hi Brian. Not too cautious, and you do have a point. Overcurrent in the form of a two pole circuit breaker is always preferred as it definitely breaks BOTH lines whichever line has the overcurrent event. Overcurrent protection on both lines with fuses is not so useful as one fuse will blow before the other, invariably leaving one fuse intact while the power is on,. If the fuse in the Neutral line is blown, then the equipment is effectively left live, and therefore by implication hazardous! My preferred outlet protection is to use two pole circuit breakers where I can, but if I must use fuses to use only one, and that in the Live feed. Permanently connected equipment on installations with ambiguous live/return connections should always be protected with a two pole CB. Portable or fixed installations connected to mains by cables with grounded plugs into socket outlets can be protected with a single fuse. Mains connections via reversible non grounded free sockets, e.g. portable Hi-Fi, TV's etc.., should be double insulated anyway, and can have a single fuse with no risk. In the UK, our LV distribution is always STAR (Y), with the centre point earthed at the transformer/distribution board. We don't ever fuse neutrals, only the lines. Dual fusing is only found in industrial fixed installations at the final outlet, never in the LV distribution system, and then usually in the form of dual fuseholder/IEC 10A inlets. Just a tuppence worth... Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Getting Started
Hi Tin. << I am interested in knowing the basis of your response to items 1 and 2, as it is contrary to my understanding of the EMC Directive.> I carefully qualified my comments with the words, 'In the UK'. The UK view on the EMC Directive is put into UK law in the form of The Electromagnetic Compatibility Regulations, Statutory Instrument SI 1992/2372. In Part IV (The Standards Route to Compliance), clause 37, it states that: "The conformity assessment requirements are complied with pursuant to the standards route to compliance if the manufacturer has applied an applicable EMC standard which makes, or all applicable EMC standards which make, complete provision in respect of the apparatus." Clause 38 then goes on to specify applicable standards. What the UK Regs effectively state is that you need to comply with ALL the relevant standards, and make a formal declaration that you have done so. This is the self certification operation - you build the equipment to all the relevant standards (EMC, LVD, Machinery, Medical Equipment etc. etc. EMC Standards are mutually exclusive, you need not meet both LVD AND Medical directives, just the most relevant) and make a legal declaration that you have done so. There is no strict requirement to provide test results to support the Declaration, though if the equipment is EMI active it's difficult to know how the Regulatory Authorities may be convinced that your declaration is sound without test results. If the equipment runs at low frequencies and very low power, it is reasonable to predict that the emissions will be very low, for instance. You are quite correct when you say that if all the standards are not met, then the TCF route should be followed, the implication being that the standards CANNOT be met rather than just the tests not carried out. Remember that the purpose of the EMC Directive is not to reduce the EMI 'smoke' around Europe, but to ensure that no Nation State gets a commercial advantage over another by allowing looser technical standards. If a machine makes more interference than the Standards permit, then a TCF must be produced that describes the equipment sufficiently that the Competent Body is happy to take responsibility for the fact that as much has been done as possible to reduce interference to a minimum. This is the whole point of the Treaty of Rome and open borders, the Euro Directives are essentially a trading tool, not a technical one. < I am interested in learning whether UK has established an updated position which allows manufacturer to waive testing (altogether) and still self-declare conformity to the EMC Directive through the standards route?> I'm not aware that the UK position has changed at all since 1996, but testing itself is not an actual requirement in UK Law. Self declaration means making a legal declaration which if proved deliberately wrong, means a stiff fine, or even Jail in some circumstances. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Getting Started
Hi Ken. << On the subject of TCF and waiving tests, lets say you were to waive a test because its non-applicable. For instance, line conducted when the unit is battery powered. Does this mean that you are required to go the TCF route? >> No. The TCF route to compliance usually means that you don't use Standards (usually because the equipment won't meet them), so there are no tests to waive. The TCF has to describe the equipment in such terms that the Competent Body will take responsibility for it's declared EMC performance, and that the EMC characteristics are minimized. This invariably means testing, but not to a particular standard. To go the Standards Route to Compliance, if a test is not applicable or relevant, then simply say so in your technical files which support your Self Declaration. Note that the term 'technical files' is NOT the same thing as a Technical Construction File - which is a reserved term described in the UK Regulations, Part V, clause 43. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: US Approval
In a message dated 29/09/00 15:15:08 GMT Daylight Time, Daryl Alden writes: << Can anybody advise me whether an MRA (mutual recognition agreement )exsists between the EU and the US? If so does this mean that electrical and mechanical products tested to CE standards do not need further approval (UL?) to be marketed in the states. >> I'm not an expert on this, but I can add a view. I don't know of any MRA's but I do know that the UL requirements and CE marking requirements are coming from very different positions. UL is essentially an Electrical/fire protective issue, while Euro/CE requirements are essentially born of Freedom of Trade. There is much UL approved material which wouldn't comply with EU rules, and vice versa. There seems little room for mutual recognition under such diverse aims. My understanding is that to sell in the States, you need to use UL material regardless of it's CE approval status. To sell in the EEC you need to have a CE mark, regardless of what safety approvals the material has. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Getting Started
In a message dated 29/09/00 15:43:06 GMT Daylight Time, fr...@amcomm.com writes: << I'm just getting started in the world of EMI and would like to ask a few questions. I'm not sure if I should be going the TCF route or the Standards Route. The company that I work for manufactures products which have many variants. 1) Is it EC law that a manufacturer must perform EMI testing before applying the CE mark? No. In the UK, the Electromagnetic Compatibility Regulations don't require testing if you follow the Standards Route. But you must make the Declaration of Compliance before you use the CE mark and be able to provide evidence of compliance to the regulatory authorities when challenged. This can be test results, or detailed analysis, or statements etc. Again, 'testing' per se is not a particular requirement. For instance, a simple resistive convection heater could be stated to Comply because there are no non-linear elements to produce or be affected by EMI. No need to test. Having said that, testing is the only absolutely certain way of proving compliance. And don't forget that the Regulations are Criminal Law! 2) If a manufacturer follows the Standards Route, does EC law require each variant to be tested? No. There is nio statutory need to test. But you need to provide firm evidence, when asked, that the variant is not significantly different in EMC terms to the original subject of the Compliance Declaration. A detailed technical statement would suffice, but must be accurate and traceable. Again, we are taking Criminal Law here! 3) If, when testing, the limit is exceeded, can the CE mark still be applied? No. The CE mark means that ALL relevant Directives have been complied with. If EMC limits are exceeded when using the Standards Route then it doesn't comply with the EMC Directive. If the product can't be produced without exceeding the limits, then the TCF route to compliance should be used. 4) Are the services of a Competent Body required in order to put together a TCF or can the manufacturer do that on his own? A TCF is only valid when qualified by a Competent Body. A manufacturer can build his own TCF, or an external Test House/Competent Body can build it, but at the end of the day the Competent Body signs/takes responsibility for it. Think of a TCF as a new EMC standard which relates ONLY to that particular product. A simple rule is 'if it complies with the Standards then use the Standards Route, if it doesn't then use the TCF route. Hope is useful. Chris Dupres Surrey, UK. >> --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: SEMI F47
In a message dated 27/07/00 17:58:48 GMT Daylight Time, bigg...@gemischova.ge.com writes: << Has anyone on this list heard of standard SEMI F47? Is there a similar european standard to this? What exactly does the standard deal with? >> Hi Daniel. The SEMI standards relate to Semiconductor FAB processes and equipment. This is a commercial standard, which is pretty well worldwide in the industry, meaning that it isn't a Government thing, or legislative thing. i.e if you don't follow it, you won't go to jail, but you won't sell anything either! It's prime purpose is to ensure commonality in Semiconductor fabrication equipment and plants where there are many hundreds of different machines and systems. F47 is just one of the many, you can find their web site, . Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: EMC and product safety split?
Hi Rob. You wrote: The name of the List is EMC-PSTC, (ElectroMagnetic Compatbility - Product Safety Technical Committee) i.e. it' covers all the material required for getting equipment documented for compliance to current legislation, in my case European rules. For that reason I find the mix both very useful and convenient. I already have far too many folders, and if the messages were seperated into two subjects I would still need to merge them into one 'Compliance' folder. I've been on this list for four or five years now, and look on it as a learned source of all things 'Compliance', rather than the actual minutae of Safety and EMC protection. The list is as much to do with the bureacracy of Compliance, the UL, NEC, BS, DIN, standards, rules, regulations, laws etc., as much as with the actual Engineering of compliant performance, filters, materials, fuses and so on. I don't need to be told how to screen, filter, fuse, cover, insulate. Those are basic Engineering matters. I do, however, need to know what I should concentrate on, what limits to work to, when I should do it, and what paperwork I will need. I would find the splitting up of the list would deviate from the original purpose of the list, and become less informative and useful. Indeed it's the width of the list that makes it much more valuable. I delete an awful lot of EMC-PSTC mail, it takes just seconds to ascetain whether to keep or chuck, but I still get gems in both Safety and EMC matters and I do check everything that comes from the list. Just my twopence worth... Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
Re: Technical Documentation
In a message dated 03/03/00 12:28:55 GMT Standard Time, cet...@cetest.nl writes: << In my opinion both TCF and Technical Documentation is meant to be the same in EC language. >> Hi Gert. Here's another way of coming at it. In the UK EMC Regulations, which is UK Law, the term 'Technical Construction File' is a legal entity. It has a particular description in the act and has to meet minimum criteria in order to enable a Competent Body to grant a compliance certificate. 'Technical Documentation' is a generic term which covers anything included in a technical file that may be used to support a claim of Compliance under the Standards Route to compliance. Technical Documentation does not have to prove compliance, it could be photo's of a test site, test results, or even a statement that the equipment does not need to be compliant! e.g. a light bulb. Chris Dupres Surrey, UK. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. 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: Jim Bacher: jim_bac...@mail.monarch.com Michael Garretson:pstc_ad...@garretson.org For policy questions, send mail to: Richard Nute: ri...@ieee.org
