[PSES] Friday question: AI-assisted software development for Safety Function?

All, Some predict that by 2028, 75% of enterprise software engineers will use AI-coding assistants, up from less than 10% in early 2023. By 2025, estimates are that 80% of the software development life cycle will involve generative AI code generation, potentially enhancing developer productivity

[PSES] "Intelligent" Power Modules?

So I just finished reading "1.2 kV/400 A SiC Source Turn-Off MOSFET Intelligent Power Module" (https://ieeexplore.ieee.org/document/10574416) The word "intelligent" in the title of the article piqued my interest. So, what's with the overuse of the term "intelligent" nowadays? When I read the art

[PSES] Plywood

All, I've been reviewing the UL 9540A fire test method, and a plywood sensor wall is recommended: "19.05-mm (3/4-in) plywood installed on wood studs and painted flat black." But no grade of plywood is mentioned. In the past, I've seen references to Grades A and B, but I assume this is a way of mi

Re: [PSES] High Touch Current in Industrial Machinery

Brian, You can try a low leakage 3-phase EMI filter design. This is where your magnetic stage(s) are unchanged and three existing large Y-caps are tied together to form a wye configuration between phases; the center tie point of the wye is not directly earthed. Instead, use a fourth Y-cap tied be

Re: [PSES] 61010-1 Stability test, Para 7.4 Stability

HI Steve, One thought that occurs to me. The method of test does not seem to mention if it is intended for final installation or during the time when the unit is mobile. By your description, I assume you intend it to be non-mobile. I did this sort of topple test once before on a telescopic constr

Re: [PSES] Reduce Speed of Moving Part to Reduce Risk

All valid points; however, I was taking my information from the established ISO/IEC standards for machinery, with which I am familiar. I do recall another standrd some years ago, mentioning contact surface area when I was looking into finger crush as well as sharp edges. And the original question w

[PSES] Arc Flash assessment

All, I am interested in locating an registered PE who can do a DC Arc Flash assessment on a battery energy storage system with an Energy Capacity greater than 4 MWh, and can provide services for the Northern Colorado USA region. PE registration within the state of Colorado is not essential in thi

Re: [PSES] AI & Regulatory Compliance

I've done some playing around with ChatGPT, Claude.AI, Perplexity.AI, BIng Chatbot, and a few others. My first test was to see if these Large Language Models (LLM) could accurately answer questions where I feel I have good expertise, such as "*How do I select a complete list of safety-critical com

Re: [PSES] Reese’s Law (P.L. 117-171) - Has the CPSC's Section 2 rule been published?

John, I've not read it in detail, but try this location: https://www.cpsc.gov/Business--Manufacturing/Business-Education/Business-Guidance/Button-Cell-and-Coin-Battery -Doug Douglas E Powell Laporte, Colorado, USA doug...@gmail.com LinkedIn

Re: [PSES] Friday Question - Line Cords in China

> that were found to work. > On 2023-08-11 15:52, Douglas Powell wrote: > > I believe you are correct. > > Simply shipping the wrong cord types to certain locations is actually > prohibited, and in general, including incorrect types could be viewed as > endorsement of their

Re: [PSES] Friday Question - Line Cords in China

lusion that ALL of the cords are suitable for use. Did I get that > right? > > > On Fri, Aug 11, 2023 at 8:00 AM Douglas Powell wrote: > >> * This message originated outside of DISH and was sent by: >> doug...@gmail.com * >> -- >>

[PSES] Friday Question - Line Cords in China

All, I was talking with a client recently about shipping line cords to various countries around the world and how some do not allow the incorrect cords within a shipment while others do. Brazil, as far as I know, does not permit incorrect cordage. Argentina, Australia, and China (PRC) are all mutu

Re: [PSES] Machine status visual Indicators

Steve, I recommend that you include this concern in your Risk Assessment to determine whether the LED color is critical to safety or not. You can then record your level of risk and compare it to your risk tolerance. Include all possible failure modes, such as LED failure, incorrect polarity, drive

Re: [PSES] Looking for AI or machine vision related ISO standards for safety

hly specialized engineering field. > > In my view, ChatGPT is a toy to ask for very general questions. It cannot > replace product safety professionals. Moreover, who is going to be > responsible if a product fails and causes harms to users when one used the > test plan generated by

Re: [PSES] Looking for AI or machine vision related ISO standards for safety

Aside from all the news articles about problems with ChatGPT, I've tried a few things myself. For example, "*write a complete test protocol for IEC 62368-1 for a desktop audio streaming amplifier weighing less than 7 kg.*" Of course, gave me a fairtly detailed but generally incomplete responses u

Re: [PSES] EStops

I would think the main concerns would be visibility, and accessibility. Possibly you could use something similar to a machinery Emergency stop pendant station, except post mounted. -Doug Douglas E Powell Laporte, Colorado USA doug...@gmail.com LinkedIn

Re: [PSES] Multiple electrical power sources

Although related to the installation of products and not necessarily the product desgins themselves, you might review NFPA 70, National Electric Code. They do have requirements when using multiple sources. -Doug Douglas E Powell Laporte, Colorado USA doug...@gmail.com LinkedIn

Re: [PSES] Comtest Architectural Shielding

Amund, I remain a little skeptical of this type of shielding and I personally would want to witness some testing where these shielding claims are made. It may be useful for E-fields, but my suspicion lies with H-fields. Some years ago, there was a company that claimed their conductive spray paint

Re: [PSES] Maintaining UL Label when Modifying Electrical Enclosures in the Field

I see this as either a configuration change or retrofit. My experience is that as long as any changes (mods, substitutions, etc) you make are in a configuration already approved by UL, and your technical files are updated, then the impact should be minimal. Oh, and this should also be done by fact

Re: [PSES] Flammability Rating for Plastics V0 vs V1

I work mainly in electrical safety standards and the term polycarbonate is not commonly used. Instead they simply say polymer, plastics, or something generic like that. As for flammable materials, the standards I work with normally require 94 V-0 for anything in direct contact with high power or h

Re: [PSES] EU and UK DoC

I'll be very curious to learn how that works out. Over the years, I have advised clients to print two copies. One for the outside of the shipping carton along with the other shipping papers. This helps to minimize the inspecting agent from opening the carton. The second copy for the inside of t

Re: [PSES] EU and UK DoC

I could be wrong but last I checked the https://www.gov.uk/ website, it's my understanding these cannot be legally combined into a single document. -Doug Douglas E Powell Laporte, Colorado USA doug...@gmail.com LinkedIn (UTC -07:00) Mountain

[PSES] Apple Files Patent for EMC Testing Chamber

Am I missing something here? Apple Files Patent for EMC Testing Chamber I don't know about anyone else, but circa 2004, I was directly involved in t

Re: [PSES] Adding more than one EUT

As I recall, this topic came up once before on this forum. But try as I might, I'm unable to find any notes on it. The idea, as I remember, was you test a single DUT, and then add another, and another, until emissions do not increase appreciably or become asymptotic with enough margin to the limi

Re: [PSES] powder coating used as insulation

32 AM Douglas Powell wrote: > All that said, I have achieved approvals from third party agencies when we > did multiple coatings. The problem with multiple coatings is that when you > apply it electrostatically, then the insulation value of the first coat > makes it difficult to apply a sec

Re: [PSES] powder coating used as insulation

Laporte, Colorado USA On Fri, Jan 13, 2023, 9:28 AM Douglas Powell wrote: > I have investigated powder coatings for basic insulation in the past. And > I had one primary concern that I was never able to fully resolve, and that > has to do with the coating thinning out at corners and

Re: [PSES] powder coating used as insulation

I have investigated powder coatings for basic insulation in the past. And I had one primary concern that I was never able to fully resolve, and that has to do with the coating thinning out at corners and edges of metallic parts. Because of the surface tension of the coating as it is applied on edg

Re: [PSES] Have PSES archives been moved or restricted?

I do believe the web page you originally linked is damaged somehow. Possibly the webmaster can repair it. -Doug Douglas E Powell Laporte, Colorado USA doug...@gmail.com LinkedIn (UTC -07:00) Mountain Time (US-MST) On Thu, Jan 12, 2023 at 11

Re: [PSES] Secondary creepage/clearance

I've had personal experience with lightning coupled transients to the secondary, strong enough to burn out an office Mr Coffee pot. Interestingly, if you have a transformer in the coupling path and the windings are oriented to normally invert a sine wave, the transient will likely not be inverted.

[PSES] Fault Tree Analysis

Greetings all, I am curious to know what folks in this community are using for FTA specifically for safety engineering. Being a top-down approach it seems like FTA is a useful companion to FMEA. The problem I have is finding a suitable software resource. There are a number of recommendations for w

Re: [PSES] Correct interpretation of EN 60950-1 or EN 62368-1

It seems interesting to me that the IEC TR 62368-2 would have two bits of text I actually don't mind seeing, but try to avoid nonetheless; Daisy-Chain and Master-Slave. It turns out that from an electrical engineering perspective, Daisy Chain translates well into other languages and is understandab

[PSES] Metric Prefix system, proposal to extend in 2022.

Finally a little relief, it was so confining before. https://www.sciencemag.org/news/2019/02/you-know-kilo-mega-and-giga-metric-system-ready-ronna-and-quecca To put these numbers into some kind of perspective, the diameter of a quark is approximately 4.3 x 10^-15 millimeters. However, a "preon" i

Re: [PSES] NFPA Codes, law or not?

d more. With a subscription to NFPA > LiNK™, you will have unlimited access to all of this! > > On Fri, Oct 30, 2020 at 1:44 PM Douglas Powell wrote: > >> Yes, >> >> This "free" version is what I was referring to about being very deficient >> with regard

Re: [PSES] NFPA Codes, law or not?

varying depending on the > agency involved. There is a table before each article which gives a > summary. Example: > > [image: image.png] > > On Fri, Oct 30, 2020 at 12:24 PM Douglas Powell wrote: > >> Rich, >> >> I knew about adoption policies and actually have a we

Re: [PSES] NFPA Codes, law or not?

nd-standards/free-access?mode=view&t=other&c=ORNEC2017> > Effective Oct. 1, 2017 > Based on the 2017 NFPA 70, National Electrical Code > Oregon amendments to the 2017 NEC *Updated Oct. 2020* > <https://www.oregon.gov/bcd/codes-stand/Documents/17oesc-table1-E-2020Oct.pdf> &

Re: [PSES] Short Circuit Current Rating (SCCR)

The referenced document in SEMI S22 R2-3 "*Example of Point-to-point Short Circuit Current Method*" does not appear to be available on the new Eaton site. But is still available on the Wayback Machine. The document is technically out of date so use it with discretion. The specific paragraph in Semi

Re: [PSES] Short Circuit Current Rating (SCCR)

Brian, The best resource I know is to do an overcurrent protection and coordination study, the same as you might do in the preliminary steps in an arc flash study. Its not dependent on the load as much as the upstream wiring and OCP devices. Unfortunately, you must start at the top, the utility t

[PSES] NFPA Codes, law or not?

My Friday Question, NFPA Codes, law or not? Officially the answer is, "No, these are not laws." I recently saw a clarification stating: "*As a national consensus safety standard, NFPA 70 is not a law and it has not been incorporated into the Code of Federal Regulations. Therefore, compliance is

Re: [PSES] Electric Current Abroad

nternet and people in a huge number of countries??? > > > > Therefore, I would, again, treat info in ECA with that proverbial “pinch > of salt”. > > > > John E Allen > > West London, UK. > > > > *From:* Douglas Powell > *Sent:* 28 October 2020 23:0

Re: [PSES] [EXTERNAL] Re: [PSES] Electric Current Abroad

ps://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.worldstandards.eu%2Felectricity%2Fthree-phase-electric-power%2F&data=04%7C01%7Cted.eckert%40microsoft.com%7C95e92ee86677454ea8df08d87b8d1659%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637395194073397525%7CUnknown%7CTWFpbGZsb3d8eyJ

Re: [PSES] Electric Current Abroad

; *Subject:* Re: [PSES] Electric Current Abroad > > > > Hi Doug, > > > > Have you seen the list from worldstandards? It doesn't cover the phase > configurations directly but does have a column for number of wires. > > > > https://www.worldstandards.eu/el

Re: [PSES] Electric Current Abroad

7;t cover the phase > configurations directly but does have a column for number of wires. > > https://www.worldstandards.eu/electricity/three-phase-electric-power/ > > On Wed, Oct 28, 2020 at 1:48 PM Douglas Powell wrote: > >> All, >> >> In the distant past I

[PSES] Electric Current Abroad

All, In the distant past I struggled to learn what were the expected electrical voltage, frequency, and phase configurations (delta, wye, high-leg, etc) for commercial/industrial facilities in various countries. I know about IEC 60038 standard voltages, but standard voltages don't always represent

[PSES] Dangers of Fractal Wood Burning

This is sad and I'm very sorry it happened. I can hardly believe people post DIY videos of this "art" without including warnings. Very telling is this quote, “*We didn’t know it was dangerous,” Caitlin said. “There were no warnings with the videos. If Matt would have known, he would have never done

Re: [PSES] Risk Assessment question

an analysis of RM and Methods for Failure Analysis is presented on > the same book in Chapters 6 and 5.* > > *I hope that above info can help you.* > > > > *Best Regards and be safe,* > > *Steli* > > > > > > > > *Steli Loznen*, M.Sc., SM-IEEE

Re: [PSES] Risk Assessment question

ble of Contents somewhere, I can scan them for you. In my > recollection, it's more of an overview of what standards are used in what > industries, vs. which risk assessment standards are specifically called out > in which product safety standards. > Mike Sherman > Graco Inc. &g

[PSES] Risk Assessment question

All, Over the past several years, nearly all safety standards have incorporated Risk Assessment (RA) as a part of their requirements. I did an informal search and found that the assessment methods are used in a wide range of disciplines from electrical products to machinery, robotics, safety softw

[PSES] Peachtree City GA

All, Over the past few months, I've been getting dozens of calls and email from recruiters in desperate need of compliance engineers. First it was for EMC and now Product Safety. If I am contacted by phone, the voice always has a strong Indian accent and barely intelligible. Area codes from eithe

Re: [PSES] Power quality issues in India

while the power quality in India may be poor, > the products are not critical and a power interruption would not be a big > deal, so it does not seem warranted. > > > > Regards, > > > > Dan > > > > > > *From:* Douglas Powell [mailto:doug...@gmail.com] >

Re: [PSES] Intertek website issue

t do > not appear in the directory, please request a verification of certification. > Americas+1-888-347-5478 > (or +1-847-660-7407) > Email etldirect...@intertek.com > > > On Wed, Mar 25, 2020 at 7:48 AM Douglas Powell wrote: > >> FYI, >> >> In tryin

Re: [PSES] Power quality issues in India

Dan, Possibly this article will be helpful, http://www.forumofregulators.gov.in/Data/Reports/Power07.pdf, check into issues like surge, sag, swell and spikes. It's only a couple of years old. Doug --- *I'm here to help you succeed!

[PSES] Intertek website issue

FYI, In trying to access the Intertek Certifications database, I ran into a problem. On the web page https://www.intertek.com/directories/, I clicked into ETL Listed Mark Directory and the error popped up. It a

Re: [PSES] NATO Standards

You are asking about classified documents which must be obtained through official channels.This of course means you will need to be checked for clearance. I would likely begin here, https://nato.usmission.gov/ Best, Doug On Wed, Feb 5, 2020, 5:17 AM wrote: > Hello, > > > > does anybody a sour

Re: [PSES] Residual Voltage Tester

e accounted for in the measurement. > > > > Some years ago I wrote an article on how to make this measurement. See > attached. > > > > I proposed this measurement scheme to TC108, but it was not accepted. > > > > Best regards, > > Rich > > >

Re: [PSES] Residual Voltage Tester

Mark, Not aware of an instrument specific to this test in North America. I always used an o'scope with storage capability after the fashion of this article. https://incompliancemag.com/article/the-capacitive-discharge-test/. A precautionary note, you must meet the high input impedance requiremen

[PSES] UL White Book

All, I presently have a copy of the UL White Book 2015-16. However, I cannot locate a more recent edition. This edition is specifically for correlation to the 2011 and 2014 National Electric Code® (NFPA 70). Since that time, there have been a number of errata, TIAs, and comments by code making p

Re: [PSES] HV relay

Sorry, typo should be IEC 60664-1. Doug On Mon, Nov 25, 2019 at 9:07 AM Doug Powell wrote: > BOštjan > > In the past when I've had to deal with this, I explained to the safety > inspector that internal spacings (clearance and creepage) are not > applicable. Nearly all IEC based standards use I

Re: [PSES] Reading or Limit Conversion?

David, In my experience, I've found that nearly all test houses accept the interpolated results. That said, the 3-meter measurement is understood to have near field issues at frequencies on the low end. Also, the 3-meter test needs to be performed in a chamber which has been tested for a uniform f

[PSES] ISO 12100: 2010(E)

All, It seems the old ISO 12100–1 and ISO 14121–1 are both replaced with ISO 12100: 2010(E). And yet ISO TR 14121-2 remains active and available ( https://www.iso.org/standard/57180.html). Throughout the 14121-2 document is reference to 14121-1, ISO 12100-1 and ISO 12100-2. My question is, can I

Re: [PSES] Do We Need Flame Retardants in Electronics?

Interesting, Nevertheless, flame retardant is entrenched and in my experience I've never had the need of it except for product certification purposes. Possibly this is mainly a CYA exercise (*cover your anatomy*). In any case, I've personally witnessed a few of the UL 94 tests, and they really do

[PSES] Vacuum hazards

All, Looking into MD and LVD using EN 60204-1 and EN 61010-1. I find absolutely nothing on vacuum hazards. Is anyone aware of guidance on this topic? Thanks so much, Doug -- Douglas E Powell doug...@gmail.com http://www.linkedin.com/in/dougp01 - -

Re: [PSES] EMC+SIPI 2019 Procedings

Sorry, that was a postcard, not email link. Doug On Wed, Sep 4, 2019 at 9:43 AM Douglas Powell wrote: > All, > > For those of you with membership in the IEEE EMC society. > > After receiving a link by email (http://www.emc2019proceedings.emcss.org > <http://www.emc2019

[PSES] EMC+SIPI 2019 Procedings

All, For those of you with membership in the IEEE EMC society. After receiving a link by email (http://www.emc2019proceedings.emcss.org ) I've made several failed attempts to download the proceedings using Firefox, Chrome and a download manager.

Re: [PSES] Stricter limits than legal (CISPR11, IEC, etc,) Where?

and double-read it.  Then I read it again.One measurement is simply not enough to build confidence.Next time someone asks you for "reasonable margin" ask them about their last wiring project  -PatrickOOO.  On Mon, Oct 12, 2015 at 2:54 PM, Dougl

Re: [PSES] Stricter limits than legal (CISPR11, IEC, etc,) Where?

Ted,Very good points. If minimum passing margins are a result of ‎edge rates on transistors, diodes or ICs, then a second source or "upgrade" to a faster device can be counterproductive with regard to the emissi

Re: [PSES] Stricter limits than legal (CISPR11, IEC, etc,) Where?

Jerry,The "stricter" limits are not limits at all. Best practice says to always provide margin.  While you may have a sample that passes with one or two dB of margin. This is usually accepted by most companies as

Re: [PSES] Wireless charging

Dale,The applicable standard is still the same as before for the product type. For example, rechargeable electric toothbrushes and cell phones would still use their respective standards.  The mechanism to do devic

Re: [PSES] requirement for spacings

Bostjan,As Scott mentioned, it is very important to know which end standard is being applied to this product. In addition there are many other factors such as environmental conditions, application, location, etc.I

Re: [PSES] Date of Withdrawal for ISO 9001?

Thanks Brian. Good information.   Doug Sent from my BlackBerry 10 smartphone on the Verizon Wireless 4G LTE network.   Original Message   From: Brian Oconnell Sent: Tuesday, September 1, 2015 5:29 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Reply To: Brian Oconnell Subject: Re: [PSES] Date of Withdrawal fo

Re: [PSES] Dielectric Grease

25 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Dielectric Grease Perhaps this is the Dow Corning 'molykote' grease? Brian From: Douglas Powell [mailto:doug...@gmail.com] Sent: Friday, August 28, 2015 10:11 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Dielectri

Re: [PSES] Dielectric Grease

iance Engineer Microsoft Corporation ted.eck...@microsoft.com   The opinions expressed are my own and do not necessarily reflect those of my employer.   From: Douglas Powell [mailto:doug...@gmail.com] Sent: Thursday, August 27, 2015 8:20 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Diele

[PSES] Dielectric Grease

All,I am trying to locate a particular high voltage insulating grease or gel.   I am unable to identify the manufacturer and ty‎pe.   The only description I can give at this point is the appearance which is green in color with an iridescent sheen. It looks much like automotive antifreeze fluid onl

Re: [PSES] CE DoI and DoC in one document.

All,I have seen two DoC with one shipment, one for the EMC portion and one for the LVD. When‎ I asked why, the answer was for administrative purposes. Apparently it was easier for the company to manage changing

Re: [PSES] Dual polarity DC electric strength test

It would seem that you need a piece of test gear with a floating output that can have either end referenced.   Not sure I have seen anything like this.Best, Doug.

[PSES] Factors affecting inception of corona

All,I am attempting to build a spreadsheet application to help with estimating corona (partial discharge of electricity), early in the product design stage. I have a good understanding of the nonlinear responses resulting from electrode geometry, electrode spacing, applied voltage, air pressure an

Re: [PSES] Production Line testing for UL60950

John I believe this question is mainly up to the IEC technical committee from which all other national versions are derived.   I see a fair number of standards and to some extent they all seem to do certain things differently.   For example, some standards require 100% routine tests for high curren

Re: [PSES] Production Line testing for UL60950

Unlike 61010-1 I don't believe 60950-1 has a specific section for your review. Instead you may wish to do a search for the phrase "routine test". I have 19 instances throughout the IEC document.  Otherwise you may need to look for "electric strength test" of which there are 94 cases and then sort t

Re: [PSES] Series Isolation

All,When I mentioned e-fields and ‎non-linear responses I had in mind the example given of series contacts, these being air gaps between metallic electrodes.   While capacitance of these may be measurable it is quite small. In addition the construction is not identically perfect meaning one will

Re: [PSES] UL Trademark and Tradename Indexes no longer public

This is interesting.  Did the UL representative give a reason?  ‎Are there proprietary or non-disclosure issues? Thanks, - doug Douglas Powell http://www.linkedin.com/in/dougp01   Sent from my BlackBerry 10 smartphone on the Verizon Wireless 4G LTE network.   Original Message   From: Carl

Re: [PSES] Safety standards versus safety engineering

John I certain cannot speak to where ‎the world is globally on this topic. I can only speak to my personal experiences when I worked at Intertek and â€Žwith several of my clients.  Of course, these are all generalizations.  If I were to define behavioral delimiters, they would be supportive, non-

Re: [PSES] Safety standards versus safety engineering

Mike,"...dismissal of identifiable risks..."Isn't this the main problem with Risk Assessment in general.   The people assigned to identify risks and catalog their risk values are almost always the same ones who design and built the product. The same goes for FMEA, and PFMEA.  The assignment of risk

Re: [PSES] Safety standards versus safety engineering

It is incumbent upon the entire organization to provide a product which is safe to use. Tort law in this country and laws of many other countries assign ultimate liability to the manufacturer and no amount of finger pointing as to whose responsibility it was will get you off the hook.  All who a