Re: [PSES] Inrush Current

ciates Rayleigh England Sylvae in aeternum manent. From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com] Sent: 10 August 2017 13:15 To: John Woodgate ; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] Inrush Current I think it also depends on what your EUT is. Machinery will typically be f

Re: [PSES] Inrush Current

average? Ralph McDiarmid Product Compliance Engineering Solar Business Schneider Electric From: John Woodgate [mailto:jmw1...@btinternet.com] Sent: Thursday, August 10, 2017 5:00 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Inrush Current Look at Annex B of IEC/EN 61000-3-3. I did a lot of

Re: [PSES] Another benefit of Time Domain EMI receivers

Do many test houses have these broadband receivers? Are they required for any tests specified in standards (military or civilian)? With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England Beware aver

Re: [PSES] Seeking 17025 calibration vendor for mixers and waveguides

That’s no doubt true, but British Telecom is pressing for EMC control to higher and higher frequencies, so the UK position may be changing. With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England

Re: [PSES] Another benefit of Time Domain EMI receivers

ave of the future, due to increased speed and better representation of broadband signals. Ken Javor Phone: (256) 650-5261 _ From: John Woodgate mailto:jmw1...@btinternet.com> > Date: Mon, 14 Aug 2017 16:38:34 +0100 To: 'Ken Javor' mailto:ken.ja...@emccompliance.c

Re: [PSES] Another benefit of Time Domain EMI receivers

am aware. They are specifically allowed for in CISPR 16-1-1, and also MIL-STD-461G, as noted. They are, in my opinion, the wave of the future, due to increased speed and better representation of broadband signals. Ken Javor Phone: (256) 650-5261 _ From: John Woodgate mailto:jmw1...@btinter

Re: [PSES] Another benefit of Time Domain EMI receivers

Re: During a recent EMC chapter meeting out here in West Michigan, I suggested that one could obtain an approximation of that kind of information by connecting a broadband oscilloscope to a high-frequency IF port of a conventional spectrum analyzer. Good point. With best wishes DESIGN IT IN! O

Re: [PSES] CE Mark

What do you mean by 'below restriction'? There are detailed rules in the Regulation about products that are only allowed to be used in some countries. But the CE mark must be affixed anyway. With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates R

Re: [PSES] CE Mark

The RED calls up the CE Mark Directive. The RED is a free download, so you need have no trouble in studying it. I would even send it to you if the list allowed attachments, but it doesn't. With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Ray

Re: [PSES] CE Mark

Sent: 15 August 2017 17:57 To: 'John Woodgate' ; EMC-PSTC@LISTSERV.IEEE.ORG Cc: 'Scott Xe' Subject: RE: [PSES] CE Mark Scott, John et al, My take on Scott's question is one that is being asked more routinely these days as the IoT spreads to many more product types

Re: [PSES] EU Blue Guide

Works for me, opening with NitroPro, so it’s not one of those that only opens with Acrobat. With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England Beware averages! They hide or discard data, and

Re: [PSES] Surge Suppression - Dos, and Don'ts

third-party testing, standards are of less significance. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opinions Only www.jmwa.demon.co.uk <http://www.jmwa.demon.co.uk/> J M Woodgate and Associates Beware averages! They hide or discard data, a

Re: [PSES] Surge Suppression - Dos, and Don'ts

>From what impedance? I know that these are successive questions, but without information about the source, nothing can be reliably designed. Standards in the IEC 62561 series might help with information. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO -

Re: [PSES] Surge Suppression - Dos, and Don'ts

andard and designing a reliable product. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates Beware averages! They hide or discard data, and may distort it (

Re: [PSES] EN 60939-1 compliance for external EMI filter

Don't use the 'standards route' to compliance. You still need a Notified Body test, but for a one-off it should be less costly than for a series production product. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opini

Re: [PSES] IEC 62368-1, 3rd edition Final Draft International Standard

It depends on which country you are in. You have to ask your National Standards body for a copy, giving reasons. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodga

Re: [PSES] Surge Suppression - Dos, and Don'ts

There's noah way to prevent such arking. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates Beware averages! They hide or discard data, and may

Re: [PSES] God EMC practice

udge, that everything is in order. The document whose URL I gave explains in fairly simple terms how to use the math. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk

Re: [PSES] God EMC practice

You are right: I replied only to the OP by mistake. I have now forwarded the post to this list. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates

[PSES] FW: [PSES] God EMC practice

Please see the URL below. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates Beware averages! They hide or discard data, and may distort it (them?).

Re: [PSES] God EMC practice

If you are manufacturing in Europe, or selling products in Europe, you have to do all those things if you want a quiet life. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Wo

Re: [PSES] God EMC practice

This sounds like more 'by guess and by god'. It's like saying the speed limit is 30, but it's actually 25. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J

Re: [PSES] Uncertainty in ESD testing

As long as your lack of fear isn't because you are not aware of the situation.. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO - Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates Beware averages

Re: [PSES] Uncertainty in ESD testing

I once kidded someone that it was a mineral, a sort of orange-blue colour, and nearly as hard as diamond. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Asso

Re: [PSES] Why higher value for DC in SELV

Look for a reply by Pete Perkins. With best wishes John Woodgate 3 Bramfield Road East, RAYLEIGH Essex SS6 8RG UK OOO – Own Opinions Only <http://www.jmwa.demon.co.uk/> www.jmwa.demon.co.uk J M Woodgate and Associates Beware averages! They hide or discard data, and may distort it

Re: [PSES] God EMC practice

CISPR standards mostly require a search for worst-case, but give examples of acceptable placement. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England Beware averages! They hide or discard data,

Re: [PSES] Routine Test 60950-1, 62368-1

If each rack-mounted product, and any power-distribution fitted in the rack itself, is routine-tested, I see no reason to test the rack as a whole, even for Europe. But you must document your decision and give reasons. With best wishes DESIGN IT IN! OOO – Own Opinions Only

Re: [PSES] Routine Test 60950-1, 62368-1

Ah, I thought you were asking about a rack of different products, not a single rack-mountable product with plug-ins. It's very unusual, I think, to routine-test subunits. But you could do that, and also test the unpopulated enclosure. The usual way of eliminating the 'long screw' issue is to ens

Re: [PSES] EN 62368-1:2014 DoW

I have flagged this up to the BSI committee, which may produce an explanation. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: Boštjan Glavič

Re: [PSES] EN 62368-1:2014 DoW

There should be an explanation of such things at the top of the OJ list, but that would require intelligence, which is contrary to policy. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK

Re: [PSES] EN 62368-1:2014 DoW

Yes, well, it's all in chaos. Several National Committees have asked CENELEC to change that date to 20 December 2020 or later. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a soverei

Re: [PSES] EN 62368-1:2014 DoW

See my recent post about chaos. It applies to EN 60950-1 as well as EN 60065. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: McBurney, Ian

Re: [PSES] EN 62368-1:2014 DoW

That's what it SHOULD be, but for some reason it was proposed to withdraw from EN 62368-1 the text that allows parts conforming to the older standards to be used, with no date of withdrawal specified. Many National Committees have said that it must not be withdrawn until 2020-12-20, but there is no

Re: [PSES] LISN Calibration Measurement Uncertainty

It's not quite as simple as it may appear. Mr Javor points out that it measures two mixtures of DM and CM voltages, which is not helpful either in fixing a design or in determining the consequent radiated emission (due to the CM component alone). The 50 ohms is indeed the input resistance of the S

Re: [PSES] LISN Calibration Measurement Uncertainty

I'm afraid that one cannot assume that our ancestors were either all-knowing or idiots. They were people, just like us, and they got it right mostly, but not always. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a so

Re: [PSES] DoW of EN 60601-1 A1

I don't know, but it's very likely. The management of the OJ lists is still in deep trouble. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From:

Re: [PSES] DOW for ETSI EN 300 386 v1.6.1

Your understanding is correct. There may be a reason why the Commission has not adopted v2.1.1, such as a problem with undated references, or it may be yet anther case of delayed updating. I expect someone here knows for sure. With best wishes DESIGN IT IN! OOO - Own Opinions Only

Re: [PSES] power strip details

UK household power strips are rated at 13 A and include a 13 A fuse. Other fuses, normally used in plugs, are 3 A, 5 A and 10 A. I have seen a 1 A fuse, but they are very rare. With best wishes DESIGN IT IN! OOO - Own Opinions Only www.jmwa.demon.co.uk J M Woodgate

Re: [PSES] power strip details

- such as those listed here http://cpc.farnell.com/search?st=plug%20top%20fuse) I believe that the standard for such UK power strips is probably BS 5733:2010+A1:2014 "General requirements for electrical accessories. Specification" - but don't have a copy and so can't comme

Re: [PSES] power strip details

hit. The Other Brian From: John Woodgate [mailto:jmw1...@btinternet.com] Sent: Friday, September 15, 2017 9:10 AM To: Kunde, Brian; EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> Subject: RE: [PSES] power strip details Is this surge suppression a) effective, b) necessar

Re: [PSES] power strip details

uipment connected to the protected output of the MSPD should survive >the surge, but equipment connected on the unprotected side may suffer >due to the unexpected diverted surge. Solution, put and MSPD on every >bit of equipment. Looks like a win-win situation for MSPD >manufacturers.

Re: [PSES] power strip details

n.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: Adam Dixon [mailto:lanterna.viri...@gmail.com] Sent: Tuesday, September 19, 2017 9:32 AM To: John Woodgate Cc: EMC-PSTC@listserv.ieee.org Subject: Re: [PSES] power strip details >Fr

Re: [PSES] Safety critical component part #'s and Agency approvals

All fluxed up! With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: John Allen [mailto:09cc677f395b-dmarc-requ...@ieee.org] Sent: Friday, Se

Re: [PSES] Marking on Remote Controls

I agree; remote control units are seldom extensively marked. Annex F of IEC/EN 62368-1 is very comprehensive but silent on this subject. Safety marking is probably not required in Europe because the voltage is too low for the LVD to apply, But the CE mark (for EMCD and RoHS) and the recycling bi

Re: [PSES] RED vs. RTTE - most important difference

It must depend on the product. With best wishes DESIGN IT IN! OOO – Own Opinions Only www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England UK is a sovereignty, not a Zollverein-ty From: Amund Westin [mailto:am...@westin-emission.no] Sent: Monday,

[PSES] European RED information

These links may be helpful: The RED Guide (non-controversial issues) has been made available on 2017-05-19: https://ec.europa.eu/docsroom/documents/23321/attachments/1/translations/en/ renditions/ native The Commission has also developed a document containing 'Frequently Asked Questions': htt

Re: [PSES] EN 61000-4-x listed on DoC?

evidence of conformity, and the 61000-4- series do not do that. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-06 15:14, James Pawson (U3C) wrote: Hi folks, Should the EN 61000-4-x standards be listed on the DoC for a product when a

Re: [PSES] NEMA 5-20P with IEC 60320 C13

It seems to me that this troublesome de-rating is due for an urgent review. Is it still really justified, since it causes all these anomalies and uncertainties? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-09 19:23, Pete Perkins

Re: [PSES] Authorized personnel only

A web search for 'ISO authorised personnel only sign' gives several hits, at least one of which cites ISO 7010. The point is that IF there is an ISO sign, and you use a different one, Big Brother may be disappointed in you. John Woodgate OOO-Own Opinions Only J M Woodgate and

Re: [PSES] NEMA 5-20P with IEC 60320 C13

rule' was brought in, and no-one has challenged it since. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-10 20:12, Ralph McDiarmid wrote: The NEC (NFPA 70) talks about “continuous currents” and when to apply the all-too-familiar

Re: [PSES] NEMA 5-20P with IEC 60320 C13

Yes, it could be difficult to change to respecting the rated values, so how about respecting the de-rated values instead? Instead of saying that you can only use this 20 A connector up to 16 A, call it a 16 A connector? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates

Re: [PSES] IEC 61000-3-2 Confusion

I agree that there appears to be a need for clarification, and I will take that up with the committee responsible. But for your particular case, what is critical is the nature of the 'triac control'. Is it phase-angle control, or 'burst firing' or something else? J

Re: [PSES] IEC 61000-3-2 Confusion

True, but it's a cumbersome procedure and is not clearly enough indicated. I will try to get an improvement. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 15:59, Scott Aldous wrote: Hi James, The flowchart in Clause 7 i

Re: [PSES] IEC 61000-3-2 Confusion

I should also have asked what the rated power actually is, and whether it's 1-phase or 3-phase? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 16:54, John Woodgate wrote: True, but it's a cumbersome procedure

Re: [PSES] IEC 61000-3-2 Confusion

ut, as you see, the standard is not totally clear in this context. I will follow up with the IEC committee. It may take a few days to get an answer. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 17:08, James Pawson (U3C) wrot

Re: [PSES] IEC 61000-3-2 Confusion

61000-3-2, -3, -11  and -12 do not have to be cited in the Generics; they apply independently. 61000-3-4 assumes a dedicated MV/LV transformer, but the product is only 3 kW, so one can't assume that. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Ray

Re: [PSES] IEC 61000-3-2 Confusion

61000-6-3 assumes a dedicated MV/LV transformer. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 19:28, Ralph McDiarmid wrote: That is an interesting technical point. Notice that EN61000-6-3 (generic residential) calls out 61000-3-2, -

Re: [PSES] NEMA 5-20P with IEC 60320 C13

Yes, of course quite a thin conductor will carry enough current to operate the protection, because it doesn't have time to get seriously hot. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 19:35, Kunde, Brian wrote: I k

Re: [PSES] IEC 61000-3-2 Confusion

previous bullet)" Which is the 'above condition' that the welder meets? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 17:08, James Pawson (U3C) wrote: Hello John, It uses phase angle control hence the concern

Re: [PSES] IEC 61000-3-2 Confusion

That isn't a 'condition'. The conditions are the items in the a-b-c list in 6.1. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-11 21:42, James Pawson (U3C) wrote: It was the symmetrical control for the powering of h

Re: [PSES] IEC 61000-3-2 Confusion

See below. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-12 09:16, James Pawson (U3C) wrote: Hi John, OK this is getting interesting, I see your point on the distinction for “conditions”. Would it specifically say “clauses” if

Re: [PSES] IEC 61000-3-2 Confusion

I am bound to be asked another question. Why have a 3 kW heater if it's always used with triac control at a firing angle of 153 degrees or higher? Is it to get very rapid warm-up at full power, then maintaining temperature will much reduced power? John Woodgate OOO-Own Opinions Onl

Re: [PSES] IEC 61000-3-2 Confusion

Hello, James. Could you please answer the question below? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-12 20:47, John Woodgate wrote: I am bound to be asked another question. Why have a 3 kW heater if it's always used

Re: [PSES] Standards - CNS, KN, SI

The KN standards certainly have numbers like CISPR and IEC standards, but of course may not be identical. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-24 16:56, Grace Lin wrote: Dear Members, I need help to find the source

Re: [PSES] SPEAG SAR Phantoms for sale

Good for Halloween! John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-25 13:21, Stephen Whalen wrote: All, I have following four SAR phantoms for sale. 2 SAMs 1 Oval 1 Dual Please contact me directly if interested. Regards, Stephen

Re: [PSES] EN 301 489-1 and RED

Maybe those manufacturers are hoping to be caught, so that they can draw attention (even in a court) to the tardiness of the updating of the OJ listings. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-10-30 06:59, Amund Westin wrote

Re: [PSES] EN 301 489-1 and RED

Understood. These desk officers! I also wasn't aware of the allowance of non-harmonized standards in some cases.  But the tardiness remains and is a blight for everyone concerned with compliance. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Ess

Re: [PSES] Plugs & sockets in bathrooms of EU

sockets are fed from an isolation transformer. The relevant standard is BS EN 61588-2-5. These sockets are, of course, unisex; they work quite well for lady-shavers. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-04 13:48, Scott Xe wrote

Re: [PSES] Plugs & sockets in bathrooms of EU

By 'unisex', I meant that it works for male and female shavers, and LGBT, of course. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-05 03:06, Scott Xe wrote: Hi John, Many thanks for your insights of this query!  I

Re: [PSES] "persons" in IEC 62368-1

Yes, the principles can be taught, but not the safety issues. I would certainly allow exposure to sources that can give a 'memorable experience' without being actually dangerous. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On

Re: [PSES] Clicks per CISPR 14-1

limit of duration as well as the 200 ms upper limit. But this probably doesn't help. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-10 10:37, Paolo Roncone wrote: Hi all, Question: IF the EUT Mains conducted emissions Quasi

Re: [PSES] Clicks per CISPR 14-1

00 ms and which is separated from a subsequent disturbance by at least 200 ms,...". Without that clarification, if the amplitude exceeds the limit for however short a time, the disturbance is a click. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

It would be better to concentrate on 62368-1, because 60950-1 is on the way out. Regarding 'adequate breaking capacity', this is in the relevant Part of IEC 60127, probably Part 3. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

You are quite right, but I wonder how many products actually use High Breaking Capacity (HBC) fuses, rated at 1500 A or so. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-12 03:37, Ted Eckert wrote: I would like to attempt a

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

I think IEC TC108 needs to review this urgently.  If no MOV can meet G.8, then the standard should not ask for the unattainable. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-13 16:40, Joe Randolph wrote: Hi John: I understand

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

ied to it. It's all about the fuse, not about what it is supposed to protect. I believe TVSs (BIG diodes with integral heat sink) are much nicer devices to use than MOVs. They don't suffer from energetic disruption. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.

Re: [PSES] UL 61010 Nameplate voltage

The Note says 'should', which is why the capacitor specification need to be checked. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-18 00:45, Richard Nute wrote: Hi Jon: “Is the same thing true for the ratings of a

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

I'm afraid that's not so. The short-circuit current of a 20 A circuit is normally at least 500 A, maybe 1500 A. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-18 03:49, Joe Randolph wrote: Yes, that is a very good poi

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

e that the particular construction standardized results in the 1500 A rating. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-20 18:26, Brian O'Connell wrote: Mr. Woodgate, Is there a recently published spec for a '

Re: [PSES] Regulatory requirements for MOVs placed line-to-ground on AC mains ports?

In UK, because of the ring-main wiring, the effective conductors to a wall-socket are 5 mm^2. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-20 20:21, Richard Nute wrote: In the USA, at the load end of a 2-meter #18 power cord

Re: [PSES] Use of LED Spots in EMC Chambers [General Use]

It's hardly surprising, is it? These lamps are not designed for the very special EMC environment of test chambers.  Lamps using a DC supply are indicated, but the DC supply itself must be specially filtered and installed outside the chamber. John Woodgate OOO-Own Opinions Only J M Woo

Re: [PSES] Use of LED Spots in EMC Chambers [General Use]

78 series regulators (except 78Sx which are switchers) do produce a little noise but I expect you have them well shielded. There are, of course, 'quieter' regulators. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-1

Re: [PSES] Safe powering 12V doorlock

V test may be acceptable for PELV, depending on which safety standard applies. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-22 17:50, Piotr Galka wrote: Dear safety experts, Help me to make me sure that it is save to use th

Re: [PSES] Safe powering 12V doorlock

But does 60950-1 apply when the application is a door lock?  In any case, I am not suggesting that any particular power supply is unreliable, but you never know what happens in installations and 'power cross' is not an unknown hazard. John Woodgate OOO-Own Opinions Only J M Wo

Re: [PSES] Safe powering 12V doorlock

it, but I think that if a potentially fatal fault, however improbable, could exist undetected, but could be neutralized by a simple earth connection, it would be good practice to provide the earth connection. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleig

Re: [PSES] Safe powering 12V doorlock

Maybe these Byzantine definitions are an attempt to reconcile conflicting views on the subject. I agree that they are singularly unhelpful. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-23 01:08, Richard Nute wrote: For

Re: [PSES] Safe powering 12V doorlock

There is no definition of PELV because the definition of 'SELV circuit' does not prohibit a connection to earth, as other definitions of SELV do. Also see Note 2: NOTE 2 This definition of an SELV CIRCUIT differs from the term "SELV system" as used in IEC 61140. J

Re: [PSES] Pickle

tects excessive current and shuts down the input to the IC. I can't give more details, in view of the limited input data. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-28 18:44, John Allen wrote: Hi, We have a pickle of a situat

Re: [PSES] UK/EU Type Approval for Automotive Components

If you don't get any useful response here, let me know and I'll refer your enquiry to the automotive EMC experts on the BSI committee. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-11-30 16:12, James Pawson (U3C) wrote:

Re: [PSES] EAC Mark in Russia

Western Europe has been found to have some 'dodgy' test houses, too, so it may not be all political. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-03 22:45, John Allen wrote: Probably due to Putin’s desire to promo

Re: [PSES] EAC Mark in Russia

Russia and its 'close friends' have recently been active in IEC, including inviting the big General Meeting to Vladivostok (!) last year.  But consistency is not a marked trait in those countries. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayle

Re: [PSES] Was there ever a comparison between IEC 60950-1 and IEC 62368-1 (current edition preferable)? And any rationale for any of the changes

reasoning ('hazard-based standard').  Of course, experience and reasoning came to the same conclusion in some cases. The 3rd edition of 62368-1 has most of the bugs removed. The 4th edition will, everyone hopes, not be very different from the 3rd. John Woodgate OOO-Own Opinions O

Re: [PSES] Was there ever a comparison between IEC 60950-1 and IEC 62368-1 (current edition preferable)? And any rationale for any of the changes

And if you print the standards, they are both made of paper. But it doesn't help. Steep learning curve! John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-06 19:48, Ted Eckert wrote: A spectrographic analysis of a plum and co

Re: [PSES] Pilot rating

, it seems, the opto to have pilot rating if the zener fails open-circuit. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-07 21:45, Jon Keeble wrote: We are getting a somewhat innovative product through UL at the moment. So there has

Re: [PSES] Pilot rating

I'm sure that in the past they have been privately amused at what some people have submitted for certification.  I recall that SEMKO were entertained by a TV set from another, nameless country, back in the 1970s, and if you can make a Swede laugh, you have won a major prize. John Woodgat

Re: [PSES] Li-Fi

LED light can indeed be modulated very quickly. Isn't that how fibre-optic cable works? John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-11 16:20, Ralph McDiarmid wrote: I haven't studied it, but seems to me that one wou

Re: [PSES] Li-Fi

His demo claims to use an ordinary LED lamp. However, the drive circuit would probably not be so 'ordinary' but not vastly more costly. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-11 16:47, Ralph McDiarmid wrote:

Re: [PSES] Temp rise measurement

. Incredibly, both IEC 60065 and IEC 62368-1 refer to the 'resistance method' without either detailing it or providing a cross reference. This is a serious omission. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-19 16:12, Scot

Re: [PSES] Temp rise measurement

I made a box with a double-pole, double-throw switch, an appliance toggle switch which is inherently break-before-make. This disconnects the supply and connects the ohmmeter in about 0.2 seconds. It takes longer to read off the resistance! John Woodgate OOO-Own Opinions Only J M Woodgate and

Re: [PSES] Temp rise measurement

Ask someone you don't like to put their finger in the way. :-) John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk Rayleigh, Essex UK On 2017-12-19 18:45, Wiseman, Joshua wrote: I’ve done similar techniques.  The only problem I’ve run into is waiting for the

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