Re: [PSES] Flicker from LED and CFL light bulbs

2017-07-31 Thread James Pawson (U3C)
Hi Ken, The Daily Mail isn't renowned for scientific rigor. Or journalistic rigor. Or rigor for that matter ;-) Nevertheless, here's a link to the article that they reference - http://theconversation.com/the-scientific-reason-you-dont-like-led-bulbs-and -the-simple-way-to-fix-them-81639.

Re: [PSES] EMC Measurement Software

2017-08-03 Thread James Pawson (U3C)
in this software will be worthwhile in the long run. Once again, many thanks! James From: James Pawson (U3C) [mailto:ja...@unit3compliance.co.uk] Sent: 01 August 2017 13:41 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] EMC Measurement Software Hello group, I'm investigating

Re: [PSES] Chamber grounding [General Use]

2017-07-18 Thread James Pawson (U3C)
Hi Brian, My understanding is that GTEMs struggle when anything involving cables is mentioned, presumably because no one can agree on an accurate, consistent, standardised method for routing them out of the test volume. 61000-4-20 has a clause in it that states that EUTs with cables are under

Re: [PSES] application of CISPR 32 to EUTs with integrated radio transmitters

2017-07-21 Thread James Pawson (U3C)
Hi Tom, I appreciate your argument, it's something I've discussed with colleagues in the past. I have tested a few products where the digital bus to the radio module has caused EMC problems. These emissions have only been visible when data is being actively transferred across the CPU - digital

Re: [PSES] application of CISPR 32 to EUTs with integrated radio transmitters

2017-07-26 Thread James Pawson (U3C)
Hi Balmukund, A good point. I've certainly used notch filters in the past for removing the intentional radiator to prove that the second harmonic is in fact an artefact of the measuring instrument. I've also done this by increasing the attenuation on the input to the analyser until the second

[PSES] EMC Measurement Software

2017-08-01 Thread James Pawson (U3C)
Hello group, I'm investigating upgrades to my existing EMC measurement software (R ESXS-K1) and have found the following options: * R Elektra (new) / ES-Scan / EMC32 * Dare RadiMation * Toyo EMC measurement software * ETS Lindgren TILE! * Nexio BAT-EMC *

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

2017-08-22 Thread James Pawson (U3C)
Hello Brian, What surge voltages are you testing to? Presumably just on the mains input? Thanks James From: Brian Ceresney [mailto:bceres...@delta-q.com] Sent: 22 August 2017 17:31 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Surge Suppression - Dos, and Don'ts Dear

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

2017-10-06 Thread James Pawson (U3C)
Thanks for all the helpful responses and clarification folks, I missed the OR statement in the directive text I quoted. Cheers and all the best James James Pawson (U3C) wrote >Hi folks, > > > >Should the EN 61000-4-x standards be listed on the DoC for a product w

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

2017-10-06 Thread James Pawson (U3C)
Hi folks, Should the EN 61000-4-x standards be listed on the DoC for a product when a standard that already calls them up is listed e.g. EN55024? By declaring compliance with EN55024 aren't you thereby referencing 61000-4-x standards by default or should they be explicitly listed? I can

[PSES] References to outdated EU directives

2017-10-10 Thread James Pawson (U3C)
Hi folks, I note that the Machinery Directive 2006/42/EU references the old version of the LVD 73/23/EEC. The latest LVD is 2014/35/EU. I'm assuming that one should be using the latest version and not the oldest one! My main question is: What is the mechanism by which references to

Re: [PSES] References to outdated EU directives

2017-10-10 Thread James Pawson (U3C)
Hi Charlie, That makes sense, many thanks for the reply :) All the best James From: Charlie Blackham [mailto:char...@sulisconsultants.com] Sent: 10 October 2017 09:19 To: James Pawson (U3C) <ja...@unit3compliance.co.uk>; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] Refe

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

2017-10-16 Thread James Pawson (U3C)
odjohn.uk> Rayleigh, Essex UK On 2017-10-11 17:08, James Pawson (U3C) wrote: Hello John, It uses phase angle control hence the concern about the harmonics generated. Manufacturer specs are single phase, 230V nominal, 3kW. Typically used at less than a 15% duty cycle, often less, in an industrial

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

2017-10-12 Thread James Pawson (U3C)
.uk> Rayleigh, Essex UK On 2017-10-11 21:42, James Pawson (U3C) wrote: It was the symmetrical control for the powering of heating elements part that was the previous condition that was fulfilled. Hope this helps James John Woodgate wrote OK, I've sent a digest to the committee

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

2017-10-11 Thread James Pawson (U3C)
gate 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 about the harmonics >> generated. >> >>

[PSES] IEC 61000-3-2 Confusion

2017-10-11 Thread James Pawson (U3C)
Hi folks, I apologise as I seem to be all take and not much give on this forum at the moment; I'm trying to do a lot of learning very quickly. Someone ask a question about HDMI so that I can feel useful! Today's question is what appears to be a contradiction in IEC 61000-3-2:2014. *

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

2017-10-11 Thread James Pawson (U3C)
not comply with the requirements of the standard, mentioning that the instruction manual must indicate to ask the supply utility for permission to connect and that additional recommendations can be found in IEC/TR 61000-3-4 or IEC 61000-3-12. On Wed, Oct 11, 2017 at 7:01 AM, James Pawson (U3C

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

2017-10-11 Thread James Pawson (U3C)
Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2017-10-11 15:01, James Pawson (U3C) wrote: Hi folks, I apologise as I seem to be all take and not much give on this forum at the moment; I'm trying to do a lot of learning very quickly. Someo

[PSES] UK/EU Type Approval for Automotive Components

2017-11-30 Thread James Pawson (U3C)
Hello all, I've got an inquiry with the UK government Vehicle Certification Agency (VCA) regarding EMC testing of automotive components but they are taking an age to respond. Does anyone here have any experience with EMC type approval of auto components? The questions I asked were: 1.

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

2017-11-22 Thread James Pawson (U3C)
There's also immunity to consider. If you are chucking around 10V/m or more then your lights could end up flickering. Could cause problems with remote monitoring via camera if monitoring brightness of a display for example. Obviously depends partly on cable routing for the lights. When I

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

2017-12-01 Thread James Pawson (U3C)
Hello all, Thanks for all the leads, contacts and information. I shall follow up with them and let you all know what I find out. Many thanks (and happy Friday) James From: James Pawson (U3C) [mailto:ja...@unit3compliance.co.uk] Sent: 30 November 2017 16:13 To: EMC-PSTC

[PSES] Unknown Regulatory Markings

2018-06-18 Thread James Pawson (U3C)
Good morning folks, I have a computer keyboard with some regulatory marks I've not come across before. Link to image: http://www.unit3compliance.co.uk/wordpress/wp-content/uploads/2018/06/corsai r-certification.jpg The one with the number 10 looks like a recycling symbol of some kind.

[PSES] UL Listing of Computer Keyboard

2018-06-18 Thread James Pawson (U3C)
Hi folks, Working with a client at the moment on a computer keyboard (hence the earlier question). I'm trying to get a handle on the applicability of UL listing and could do with some help. Is UL listing mandatory for IT accessories like keyboards? My searching so far suggests that the

Re: [PSES] Unknown Regulatory Markings

2018-06-18 Thread James Pawson (U3C)
Thanks Andreas and Chris for the help, will do some more looking in to the requirements. All the best James From: Graevinghoff Andreas (ETAS/EHS2) Sent: 18 June 2018 09:25 To: James Pawson (U3C) ; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] Unknown Regulatory Markings Hi

Re: [PSES] UL Listing of Computer Keyboard

2018-06-24 Thread James Pawson (U3C)
Hi Richard, Most useful, thank you for the email :) All the best James Richard Nute wrote > > >Hi James: > > > >Some additional information in response to your conclusions: > > > >* NRTL approval legally required for selling in the USA? No. > > > >There is no Federal law,

Re: [PSES] UL Listing of Computer Keyboard

2018-06-20 Thread James Pawson (U3C)
inions expressed are my own and do not necessarily reflect those of my employer. From: James Pawson (U3C) mailto:ja...@unit3compliance.co.uk> > Sent: Tuesday, June 19, 2018 1:56 AM To: EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> Subject: Re: [PSES] UL L

[PSES] EMCD harmonised standard references out of date standards

2018-07-02 Thread James Pawson (U3C)
Hi folks, Product in question is a masthead amplifier, previously tested to EN 50083-2. This standard (still listed in OJ for EMCD) makes extensive references to EN 55013 (superseded by EN 55032) and EN 55020 (superseded by EN 55035, not in OJ yet). My argument would be to use 55032/35

Re: [PSES] EMCD harmonised standard references out of date standards

2018-07-03 Thread James Pawson (U3C)
<http://www.woodjohn.uk> Rayleigh, Essex UK On 2018-07-02 20:22, James Pawson (U3C) wrote: Hi folks, Product in question is a masthead amplifier, previously tested to EN 50083-2. This standard (still listed in OJ for EMCD) makes extensive references to EN 55013 (superseded by EN 55032)

Re: [PSES] Mains Conducted rf emissions measurements

2018-04-26 Thread James Pawson (U3C)
Hi Ian, Could you turn the LISN around to measure the noise on the feed for your chamber? Might give you some useful pointers. All the best James From: McBurney, Ian Sent: 26 April 2018 15:43 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Mains

[PSES] BS-1363 UK Plugs - non recognised BSI Kitemark numbers

2017-10-23 Thread James Pawson (U3C)
Hi folks, My understanding is that three pin UK mains plugs to BS 1363 must be approved by a notified body (Plugs and Sockets regs 1994 - http://www.legislation.gov.uk/uksi/1994/1768/made) I've got a customer with a mains cord assembly that uses a BS 1363 plug with a BSI KM number that

Re: [PSES] CI Software Flicker/Harmonics

2017-12-20 Thread James Pawson (U3C)
Full sympathies. Currently Win98 here! James Kunde, Brian wrote >It will be difficult for me to ask what I want without insulting California >Instruments (Emetek), so I apologize in advance if I fail. For those of you >who owns a CI CTS Series for doing Harmonic and Flicker

Re: [PSES] UL Listing of Computer Keyboard

2018-06-19 Thread James Pawson (U3C)
reply to your Emails and are happy to discuss the project with you. 10 years ago, it was a lot different ! Regards Darren. On Monday, 18 June 2018, 9:40, James Pawson (U3C) mailto:ja...@unit3compliance.co.uk> > wrote: Hi folks, Working with a

Re: [PSES] RF immunity - audio noise in headsets

2018-09-05 Thread James Pawson (U3C)
Hi Amund, hope you are well. Some general thinking aloud follows, some of which you may have already considered. I would have expected that some kind of non-linear function (e.g. diode) would be required to demodulate the AM RF carrier. This is unlikely to be present in a "dumb" speaker

Re: [PSES] RF immunity - audio noise in headsets

2018-09-05 Thread James Pawson (U3C)
Hi Ian, That's interesting, thanks. What connector and cable technology do your products end up getting used with? RCA/phono or XLR? All the best James From: McBurney, Ian Sent: 05 September 2018 08:51 To: James Pawson (U3C) ; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] RF

[PSES] CE marking - mixture of responsibilities

2018-08-30 Thread James Pawson (U3C)
Hello all, I'm working with a company who are importing some IT products from China to the EU. The Chinese manufacturer is taking a very much "hands off" approach to approvals, expecting the importer to draw up the DoC and perform much of the testing. However access to the parts of the

Re: [PSES] EMCD harmonised standard references out of date standards

2018-07-13 Thread James Pawson (U3C)
gh, Essex UK On 2018-07-02 20:22, James Pawson (U3C) wrote: Hi folks, Product in question is a masthead amplifier, previously tested to EN 50083-2. This standard (still listed in OJ for EMCD) makes extensive references to EN 55013 (superseded by EN 55032) and EN 55020 (superseded by EN 55035, n

Re: [PSES] Automatic measurement with Class 2 laser

2018-01-22 Thread James Pawson (U3C)
Hi Charlie, A slight aside: I'm not a laser expert, but is there a way of soft starting the laser over the course of a couple of seconds, perhaps via PWM, that could be used to mitigate the hazard associated with sudden beam appearance? All the best James From: Charlie Blackham

Re: [PSES] AW: [PSES] FW: HBES/BACS Standards in the OJ

2018-03-15 Thread James Pawson (U3C)
50491 will be replaced by their IEC 63044 counterparts. Kind regards, Bernd Von: James Pawson (U3C) [mailto:ja...@unit3compliance.co.uk] Gesendet: Donnerstag, 15. März 2018 09:11 An: EMC-PSTC@LISTSERV.IEEE.ORG Betreff: Re: [PSES] FW: HBES/BACS Standards in the OJ Hi John, Do you have an id

Re: [PSES] FW: HBES/BACS Standards in the OJ

2018-03-15 Thread James Pawson (U3C)
Hi John, Do you have an idea why a new series of standards are being introduced rather than updating the older ones? Thanks James From: John Woodgate Sent: 14 March 2018 23:19 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] FW: HBES/BACS Standards in the OJ

Re: [PSES] Looking for writer for EMC Filters

2018-03-26 Thread James Pawson (U3C)
I've just had a look on various booksellers and it doesn't appear to be available anywhere :( James From: Ken Javor Sent: 26 March 2018 17:21 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Looking for writer for EMC Filters Actually, Mark Nave

[PSES] EMC tests called up in Safety standards

2018-03-20 Thread James Pawson (U3C)
Hello experts, I note that EN 60335-1 (household and similar appliances) specifically calls up EMC immunity tests in clause 19.11.4 where the controls for the EUT are set in the "off position" and a set of immunity tests are applied. For something that controls a heating element, I can see why

Re: [PSES] EMC tests called up in Safety standards

2018-03-21 Thread James Pawson (U3C)
d risk analysis as called out in the new LVD. For Europe only, of course. The difference between functional and safety related EMC is an evolving discussion, lately triggered by accidents with hybrid and autonomous driving cars. Gert Gremmen On 20-3-2018 10:27, James Pawson (U3C) wrote: Hello e

Re: [PSES] Neat Funny Stories regarding EMI

2018-03-23 Thread James Pawson (U3C)
Hi Charles, https://www.google.co.uk/search?q=emc+banana+skins Enjoy James From: Grasso, Charles Sent: 23 March 2018 14:49 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Neat Funny Stories regarding EMI Hi all, I am writing a column internal to my

Re: [PSES] Field probe calibration

2018-03-04 Thread James Pawson (U3C)
Hi David, An interesting set of results! I'm going to ask some questions that I'm sure you've already considered so please bear with me being Captain B. Obvious. Do your field probes use frequency correction? I'm not familiar with a wide range of probes but my Narda PMM field probe has an

Re: [PSES] NFC (near field communication): FCC Approach?

2018-10-20 Thread James Pawson (U3C)
Hello Mike, The radiated emissions measurements I've made on NFC card readers and tags have been overwhelmingly quiet. Certainly no significant emissions from the intentional radiator part. The biggest contributor to any radiated emissions test was the system digital controller and emissions

[PSES] 62368-1 - Resistive PIS Question

2018-11-15 Thread James Pawson (U3C)
Hi folks, I seem to be more take than give at the moment, my apologies. IEC/EN 62368-1 classifies ignition hazards as a Potential Ignition Source (PIS) A resistive PIS is any part in a PS2 or PS3 circuit that: - dissipates more than 15 W measured after 30 s of normal operation; OR

Re: [PSES] 62368-1 - Resistive PIS Question

2018-11-16 Thread James Pawson (U3C)
James From: John Woodgate Sent: 15 November 2018 19:07 To: James Pawson (U3C) ; EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] 62368-1 - Resistive PIS Question There is no such thing as 'RMS power'. The product of RMS voltage and current which are in phase is average power. In IEC standards

[PSES] Low Frequency Spectrum Analyser for RE101

2018-11-14 Thread James Pawson (U3C)
Hello all, I'm helping a customer out with some MIL-STD-461 pre-compliance but am struggling to find a spectrum analyser or receiver for the RE101 test - 30Hz to 100kHz, RBW 10Hz and 100Hz. All my spectrum analysers stop at 9kHz. I'd prefer to avoid having to pay top whack for a posh R

Re: [PSES] Low Frequency Spectrum Analyser for RE101

2018-11-14 Thread James Pawson (U3C)
Hello all, Thank you very much for all the helpful replies. I managed to get a good deal on a hired spectrum analyser. Whilst this is a one off test I'll keep my eye on eBay to see if one comes up. All the best James From: James Pawson (U3C) Sent: 14 November 2018 08:34 To: EMC

Re: [PSES] Fully anechoic chamber vs. Semi-anechoic chamber

2018-11-12 Thread James Pawson (U3C)
Hi Amund, One place to start is looking at the difference in limits in EN 55032 for a SAC and for a FAR (see attached graph). Above 230MHz the chart is 5dB lower to account for the lack of a reflective ground plane. I don't know how the upward-sloping compensation below 230MHz was derived

Re: [PSES] CE marking - mixture of responsibilities

2018-08-30 Thread James Pawson (U3C)
angerously unaware of the EU requirements, or they are deliberately avoiding commitment. John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2018-08-30 08:48, James Pawson (U3C) wrote: Hello all, I'm wo

Re: [PSES] Sometimes the simple aspects aren't

2018-09-03 Thread James Pawson (U3C)
Hi Mark, What about stud welding? https://www.taylor-studwelding.com/about-stud-welding#problems HTH James From: Mark Hone Sent: 03 September 2018 10:17 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Sometimes the simple aspects aren't Dear List Members, I have been asked

Re: [PSES] Equipment EMI Issue

2018-09-26 Thread James Pawson (U3C)
Hi Robert, How have they identified conclusively that your equipment is responsible? James From: Moeller, Robert T. Sent: 26 September 2018 14:41 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Equipment EMI Issue Hello, Maybe someone can help with this question: We have had one

Re: [PSES] MIL-STD-461 and power cables sanity check

2019-01-15 Thread James Pawson (U3C)
, the dc power would be subjected to the wording you cited, but the ac power would not. Ken Javor Phone: (256) 650-5261 _ From: "James Pawson (U3C)" mailto:ja...@unit3compliance.co.uk> > Reply-To: "James Pawson (U3C)" mailto:ja...@unit3compliance.co.uk> >

Re: [PSES] World Weather

2019-01-15 Thread James Pawson (U3C)
Slightly OT but I find http://windy.com absolutely fascinating viewing! All the best James From: Charlie Blackham Sent: 15 January 2019 19:38 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] World Weather Doug ETSI publish a number of standards with environmental conditions and

[PSES] MIL-STD-461 and power cables sanity check

2019-01-15 Thread James Pawson (U3C)
Hello all, MIL-STD-461 has a requirement for any conductors in a cable assembly carrying "primary power" i.e. AC power from a vessel distribution bus to be separated out from the main cable bunch and routed separately in a test setup (clause 4.3.8.6). It also states that the primary power

Re: [PSES] Radiated RF Immunity vs. Radio Module

2018-12-03 Thread James Pawson (U3C)
antenna and it's fine at 3V/m immunity. With an additional SAW filter in line with the antenna feed it passes at 10V/m. I really appreciate the assistance, having a community of people to bounce ideas off is invaluable for lone workers like me. Cheers. James From: James Pawson (U3C

Re: [PSES] Radiated RF Immunity vs. Radio Module

2018-11-27 Thread James Pawson (U3C)
ts.com Main:510-578-3500 Fax:510-440-9525 From: James Pawson (U3C) [mailto:ja...@unit3compliance.co.uk] Sent: Tuesday, November 27, 2018 6:03 AM To: EMC-PSTC@LISTSERV.IEEE.ORG <mailto:EMC-PSTC@LISTSERV.IEEE.ORG> Subject: [PSES] Radiated RF Immunity vs. Radio Module Hello, I have

Re: [PSES] Radiated RF Immunity vs. Radio Module

2018-11-27 Thread James Pawson (U3C)
performance. Ken Javor Phone: (256) 650-5261 _ From: "James Pawson (U3C)" mailto:ja...@unit3compliance.co.uk> > Reply-To: "James Pawson (U3C)" mailto:ja...@unit3compliance.co.uk> > Date: Tue, 27 Nov 2018 14:02:57 - To: mailto:EMC-PSTC@LISTSERV.IEEE.OR

[PSES] Radiated RF Immunity vs. Radio Module

2018-11-27 Thread James Pawson (U3C)
Hello, I have a puzzling query today. I'm testing a product with an integrated radio module for 868MHz Zigbee. The EUT has an internal antenna connected to the UFL connector of the module. This means the wanted signal is provided by an antenna inside the test environment. The standard

[PSES] Cable Flammability Standard Comparison

2019-01-07 Thread James Pawson (U3C)
Hello all, Happy new year folks, I hope 2019 brings health and happiness to you all. I'm trying to gain a better understanding of cable flammability standards. Safety standard EN 62368-1 states that, for PS2 and PS3 circuits, wire insulation flammability should meet the requirements of

Re: [PSES] Cable Flammability Standard Comparison

2019-01-08 Thread James Pawson (U3C)
Hello folks, Thank you to everyone who replied with the information and further reading; it was most helpful. I'm still on the EN version of the 2nd edition which is why I hadn't spotted the update. All the best James From: James Pawson (U3C) Sent: 07 January 2019 15:55 To: EMC

Re: [PSES] How to lose another million dollars

2018-09-14 Thread James Pawson (U3C)
Hi John, Is this an actual true story? I'm lost for words... James From: John Woodgate Sent: 14 September 2018 12:57 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] How to lose another million dollars Prepare for sob story. Company X has implemented the sensible policy of making the

Re: [PSES] New EU enforcement regulations touches on all? product regulations/directives.

2019-02-15 Thread James Pawson (U3C)
I've had a couple of inquiries recently from potential customers who have said "we want to sell this on Amazon but they are asking for an EMC report?" so maybe Amazon are (finally) starting to ask the right questions. I've seen non-EMC-compliant but CE marked power supplies sourced from Amazon

Re: [PSES] Testing a product with that uses a solar panel

2019-02-15 Thread James Pawson (U3C)
Hi Charles, hope you are well In a previous job we used a xenon arc searchlight, originally intended for naval use, for making solar heat loading measurements on outdoor high brightness LCD monitors. This was roughly calibrated with temperature measurements on a matt black metal plate the same

Re: [PSES] Exemptions from UK Plugs and Sockets Regulations

2019-04-12 Thread James Pawson (U3C)
Hi Charlie, Not my speciality, but doesn't the requirement in EN 62368-1 require compliance with BS 1363? 4.7 Equipment for direct insertion into mains socket-outlets . 4.7.2 Requirements The mains plug part shall comply with the relevant standard for the mains plug. I'm not sure if

Re: [PSES] DC/DC EMI Input Filter Stability

2019-06-05 Thread James Pawson (U3C)
nt: 04 June 2019 17:53 To: James Pawson (U3C) ; EMC-PSTC@LISTSERV.IEEE.ORG Subject: RE: [PSES] DC/DC EMI Input Filter Stability Typically we handle each DC to DC as separate entities and filter locally. Having said that - are you trying to solve and EMI problem or trying to prevent

Re: [PSES] DC/DC EMI Input Filter Stability

2019-06-05 Thread James Pawson (U3C)
http://www.electrical-integrity.com/Paper_download_files/DC17_PAPER_11_Overv iewComparisonPowerConverterStability_Hartman.pdf Regards, Istvan Novak Samtec On 6/4/2019 3:45 AM, James Pawson (U3C) wrote: Morning all, ? I?m designing an EMI filter for a DC input power line that has four DC/DC

[PSES] DC/DC EMI Input Filter Stability

2019-06-04 Thread James Pawson (U3C)
Morning all, I'm designing an EMI filter for a DC input power line that has four DC/DC converters all running off it. I know that the output impedance of the EMI filter needs to be much lower than the input impedance of the DC/DC converter to prevent oscillation/instability. But what

Re: [PSES] Question re: Measuring a signal in a noisy environment

2019-04-23 Thread James Pawson (U3C)
Hi John, Something you wrote earlier has puzzled me a little. I’ve summarised the thread below, hopefully retaining the original context JMW: I doubt anyone would disagree with that. But if a company allows a test house to impose compliance, how can it know that the result is reliable?

Re: [PSES] GTEM cell used for RE measurement

2019-08-13 Thread James Pawson (U3C)
Hello Ken, Thinking aloud here: would such a factor exist as a generic formula? If I think about this the other way round, putting 1V of RF into the coax connector will generate 1V between the septum and ground (or between the septums? septii? in the case of a differential GTEM like a

Re: [PSES] GTEM cell used for RE measurement

2019-08-13 Thread James Pawson (U3C)
lways ends in 'a'. Write 100 times. ;-) Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-08-13 07:47, James Pawson (U3C) wrote: Thinking aloud here: would such a factor exist as a generic formula?

[PSES] Cable Arrangement and Separation in EN 61000-4-3 Radiated Immunity Test

2019-08-01 Thread James Pawson (U3C)
Hello experts, I am performing some testing on a control panel with multiple cable connections and it has got me thinking about the radiated RF immunity testing. I know from the EN 61000-4-3 standard that "1m of cable is exposed to the electromagnetic field" in the Uniform Field Area (UFA).

[PSES] Railway Earthing and Isolation Requirements - Rolling Stock and Trackside Equipment

2019-07-19 Thread James Pawson (U3C)
Hello experts, I'm working with a company designing some equipment for both rolling stock and trackside applications for rail applications. Information about earthing schemes for this type of equipment seems to be ill defined. The customer has been given the (vague) requirement that they

Re: [PSES] Railway Earthing and Isolation Requirements - Rolling Stock and Trackside Equipment

2019-07-19 Thread James Pawson (U3C)
you looked at IEC TC9 publications? Go to: https://www.iec.ch/dyn/www/f?p=103:22:0FSP_ORG_ID:1248 Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-07-19 09:40, James Pawson (U3C) wrote

Re: [PSES] Railway Earthing and Isolation Requirements - Rolling Stock and Trackside Equipment

2019-07-19 Thread James Pawson (U3C)
& Vibration <http://www.unit3compliance.co.uk/> www.unit3compliance.co.uk -- 07811 139957 Opening Hours: Tuesday to Friday, 0830 to 1800. Closed Monday. From: James Pawson (U3C) Sent: 19 July 2019 09:40 To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Railway Earthing and Isolation Re

[PSES] CISPR 25 Limits for conducted disturbances - guidance for selecting emissions class

2020-02-05 Thread James Pawson (U3C)
Hello experts, Can anyone point me towards any guidance for selecting the appropriate CISPR 25 emissions Class (1-5) based on installation of equipment within a vehicle? The standard states "The level class to be used (as a function of the frequency band) shall be agreed upon between the

Re: [PSES] [EXTERNAL] Re: [PSES] Mandatory certification

2020-02-17 Thread James Pawson (U3C)
Hello Peter, For the EMC/EMI side of things, I believe the table in CFR 47 15.101 is the key. The Suppliers Declaration of Conformity (SDoC) path means no formal certification is required.

Re: [PSES] SV: [PSES] Ground copper fill on signal layer on multilayer PCB

2020-02-19 Thread James Pawson (U3C)
Hi Amund, If you have the space on the board then a ground fill around the perimeter (on all layers) probably won’t do any harm. Whatever ground fill strategy you decide on for the signal layer I would make sure it is well connected with vias to both of the adjacent planes along the edge

Re: [PSES] CISPR 25 Limits for conducted disturbances - guidance for selecting emissions class

2020-02-11 Thread James Pawson (U3C)
/ Consultancy / Environmental & Vibration www.unit3compliance.co.uk <http://www.unit3compliance.co.uk/> -- 07811 139957 Opening Hours: Tuesday to Friday, 0830 to 1800. Closed Monday. From: Matthew Wilson | GBE Sent: 07 February 2020 21:24 To: James Pawson (U3C) ; EMC-PSTC@LISTSERV.IEEE.O

Re: [PSES] EMC/E-Mark conformity tests

2020-04-21 Thread James Pawson (U3C)
Hi Scott, “The noise source should come from the unit plugged in, very low noise from the charger itself." That depends on if the charger is using a DC/DC converter in which case this may not be true! ;) James James Pawson EMC Problem Solver Unit 3 Compliance Ltd EMC

Re: [PSES] HDMI distribution amplifier (1:4) and HDMI cable recommendations?

2020-03-31 Thread James Pawson (U3C)
Adam, I’ve been having success with these HDMI cables. Not dissected one yet but they seem to be pretty good from a radiated emissions point of view. You’ll have to check if they are available in the USA. https://www.amazon.co.uk/dp/B01K1X1QV2/ref=pe_3187911_189395841_TE_dp_1 No

Re: [PSES] EMC and Scalar Waves - Friday Pondering

2020-04-27 Thread James Pawson (U3C)
Hi Charles! I'm just a simple lad from Yorkshire meaning I usually need things explaining to me with lots of pictures (sometimes in crayon) and words of less than one syllable. As such, I'm about to mangle some terminology I'm sure. Any wave travelling through space is going to interact

Re: [PSES] EMC testing for IVD equipment

2020-05-04 Thread James Pawson (U3C)
This is consistent with a customer of mine making a device for stroke patient rehab in a clinic setting. They've been told that 60601-1-2 is required. Will ask them where this requirement came from. All the best James James Pawson The EMC Problem Solver Unit 3 Compliance Ltd

Re: [PSES] Stripline - discontinuity in adjacent ground planes

2020-03-18 Thread James Pawson (U3C)
Hi Amund, Are the distances from GND1-Signal the same as Signal-GND2 i.e. is the Signal layer equidistant between the two GND layers? If so, broadly speaking, half of the field is going to be between GND1 and signal and the other half will be between GND2 and signal. If the signal layer

Re: [PSES] In-house Conducted emission test equipment

2020-09-04 Thread James Pawson (U3C)
Hi Amund, You might want to look at the Narda 9010F receivers https://www.narda-sts.it/eng/products/receivers/9010f/ I've heard good things about them and the scan speed with the FFT technology would be most valuable for pre-compliance! They also make LISNs. All the best James James Pawson

Re: [PSES] integrated or non-user serviceable Li-ion batteries

2020-05-20 Thread James Pawson (U3C)
Hello Chester, You might want to check out Annex M of 62368-1 which has some guidance on secondary lithium batteries. I'm helping a customer with their evaluation at the moment. We've found conflicting info from the battery manufacturer and incomplete testing from the previous safety test

Re: [PSES] "Singing probe"

2020-08-05 Thread James Pawson (U3C)
Hello Rick, Thinking aloud: Could it be magnetostriction of the core and windings? Perhaps this could be exacerbated by a probe with some foreign material in the gap? All the best James Rick Goodwin wrote >Hello, > >A question for the experts. While doing an automotive BCI test,

Re: [PSES] SV: [PSES] Thoughts on what may be the emission source

2020-11-28 Thread James Pawson (U3C)
Derek, I agree with Amund. Narrowband 240MHz (high speed mode clock rate) and 480MHz (second harmonics from low differential pair matching) are classic USB emissions. There may be a little something at 960MHz of 1.44GHz as well. I've had good results from RasPi boards in the past with USB so

[PSES] EN 61000-6-2:2019 - Missing Annex ZZ?

2021-01-15 Thread James Pawson (U3C)
Hello EMC-ers, happy new year to everyone. I've just been looking at the redline version of EN IEC 61000-6-2 (Industrial Immunity) from 2006 to 2019 versions. It appears that the Annex ZZ (that links the standard to the Essential Requirements of the EMC Directive) is missing on the new

Re: [PSES] AW: [PSES] EN 61000-6-2:2019 - Missing Annex ZZ?

2021-01-18 Thread James Pawson (U3C)
bably take considerable time until a new definition has been agreed upon, TC 210 decided to publish the standards without Annex ZZ to make them available. Kind regards, Bernd Von: James Pawson (U3C) < <mailto:ja...@unit3compliance.co.uk> ja...@unit3compliance.co.uk> Gesendet: Freit

Re: [PSES] Keytek EMC Pro direct surge output question

2020-12-11 Thread James Pawson (U3C)
Hi Bob, I know my KeyTek ECAT does have the 18uF. Not sure if that helps much though. James James Pawson The EMC Problem Solver Unit 3 Compliance Ltd EMC Testing / Design for EMC / Problem Solving / Pre Compliance / Consultancy / Environmental & Vibration

Re: [PSES] ISO 7637-3 (automotive)

2021-02-02 Thread James Pawson (U3C)
February 2021 14:48 To: James Pawson (U3C) Cc: EMC-PSTC@listserv.ieee.org Subject: Re: [PSES] ISO 7637-3 (automotive) We created the document specific to the transportation industry so predominantly automotive but I am also aware of agriculture, truck & bus, and even avionics/aeros

[PSES] ISO 7637-3 (automotive)

2021-02-02 Thread James Pawson (U3C)
Hello experts, Does anyone know what standards call up or mandate the use of the automotive standard ISO 7637-3 (coupling of noise onto non-supply lines)? There is nothing in R10.06 or ISO 7637-2 that I can see. Thanks in advance James James Pawson Unit 3 Compliance Ltd

Re: [PSES] ISO 7637-3 (automotive)

2021-02-02 Thread James Pawson (U3C)
-materials-technology?challengeId=AQFf9AemZ4SobwAAAXOQwivOsnkHiTt2ByoCkOxVQjOGOjRlivicVgYlN1dz5QXjId9bpa0keWzfVxhl8KPj78uD6-S6nfqRsg=e49e0dc0-96a3-2516-27fa-ee2e8c42b177> <https://twitter.com/ElementTesting/> <https://elementmaterials.eu.qualtrics.com/jfe/form/SV_3xQqm84s6

[PSES] Product for detecting missing earth connection

2021-06-23 Thread James Pawson (U3C)
Hello experts, Does anyone know of an off-the-shelf product for detecting the presence of an Earth connection on an incoming AC supply? There are plenty of ways of detecting earth fault currents like RCDs and GFCIs but I seem to be hitting a block finding something that explicitly monitors

[PSES] Overvoltage Categories (OVC) and "Reliable" Earthing - 62368-1 vs 60601-1

2021-06-15 Thread James Pawson (U3C)
Hello safety experts, A question regarding overvoltage categories and "reliable" earthing and some differences between standards. I would be interested to hear your thoughts. Background: When determining the required withstand voltage for insulation, EN 62368-1 states that: 5.4.2.3.3

Re: [PSES] What percentage of products pass first time?

2021-05-25 Thread James Pawson (U3C)
(replying even though I’m not a guru) Hi Charles, hope all is well with you Speaking from my own experience. Over the last four years of running a consultancy, pre-compliance and low cost test EMC laboratory I would (very roughly) estimate that around: * 50% of products pass their

[PSES] Safety Question :: Isolation requirements for AC supply: phase-phase and phase-neutral

2021-05-22 Thread James Pawson (U3C)
Hi all, Currently helping a customer with a 3-phase power monitoring product to get their electrical safety in order. I understand the requirements for safety isolation from hazardous live/ES3 to user accessible terminals/ES1 based on the possible mains transient voltage of up to 2500Vpk (OVC

Re: [PSES] Surges on Ethernet ports under 62368-1

2021-07-09 Thread James Pawson (U3C)
Hi Peter, It would align with the guidance in IEC 61000-4-5 for applying surges to 'long distance lines and outdoor lines' which would include Ethernet leaving a building. The built in voltage isolation of the Ethernet magnetics handles 1kV surges just fine. Main risk is a poorly implemented

Re: [PSES] Automotive EMC training

2021-01-27 Thread James Pawson (U3C)
On the subject of Kens – in the Scottish dialect, to “ken” is to understand or know something as in “oh aye I ken tha’ EMC problem” So congratulations to all Kens, you are one step ahead of the rest of us. All the best Ken…Sorry… I mean James. James Pawson The EMC

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