Re: [PSES] hipot test

Hi Ken: If the dc lines are subject to lightning, e.g., solar panels, then transients can exist on the dc line. If the dc powers several equipments, then switching transients can exist on the dc line. The more equipment is connected to the dc, the more switching transients. In

Re: [PSES] hipot test

If the hipot test can degrade the insulation (we’re talking about a single test on the production line), then the insulation system is not up to par. Good point! Best regards, Rich - This message is from

Re: [PSES] X & Y Cap rating due to hipot test

Hi Ken: For safety purposes (protection against electric shock), insulation between the mains and the human body must not only withstand the mains voltage, but also must withstand transient voltages on the mains. These transients are normal and are generated by normal load switching and

[PSES] insulation resistance testing

I have pointed this out in the past, but it didn't have any effect. Me, too. Momentum? I find that standards committee members rationalize keeping old requirements by saying, "We have no problems therefore the requirement is working." On the other hand, customer/client specs

Re: [PSES] X & Y Cap rating due to hipot test

Hi Ken: Do the hi-pot test without the caps. If the caps don't outright fail, the test will have done some damage to them. (I assume the caps for a 28-volt motor are rated much less than 1000 volts!) Depending on the construction, the caps could fail near short or could fail

Re: [PSES] X & Y Cap rating due to hipot test

Hi Ken: Insulation resistance test and hi-pot test are two distinctly different tests. Insulation test (measurement) must be done with dc and is to measure the resistance of the solid insulation. The insulation resistance meter is a high-resistance ohmmeter; as such it needs a high-voltage

Re: [PSES] X & Y Cap rating due to hipot test

650-5261 _ From: Richard Nute mailto:ri...@ieee.org> > Reply-To: mailto:ri...@ieee.org> > Date: Tue, 14 Aug 2018 11:19:08 -0700 To: mailto:EMC-PSTC@LISTSERV.IEEE.ORG> > Subject: Re: [PSES] X & Y Cap rating due to hipot test Hi Ken: Do the hi-pot test without

[PSES] hipot test

Hi Doug: I've always viewed the purpose of hipot testing as verification only. During engineering type testing, it is design verification. I disagree. The hi-pot test determines the minimum electric strength of the insulation system. Design is an indirect measure of electric

Re: [PSES] hot laptop

Its not the temperature, but the thermal energy that is transferred to a body part. Consider aluminum foil versus cast aluminum at the same temperature, say 140 F. The foil won’t burn you, but the cast aluminum sure will! The thermal resistance of plastic will give you the time to

[PSES] hot laptop

Get a new laptop. Intel devices now slow down if they get too hot. My new laptop barely gets warm. Rich From: Nyffenegger, Dave Sent: Thursday, August 16, 2018 7:35 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] CB Certificate For Samsung Tablet - Need Contact I’d like

Re: [PSES] External toothed star washer used in earth connection

"The lock washer should not interface between the bolt head and the metal, the lock washer should be between the head and a flat washer." That locks the bolt to the flat washer so they turn together.  Establishes a good electrical connection between the bolt and the flat washer! 

Re: [PSES] External toothed star washer used in earth connection

Hi Ted: Thanks for the bonding and grounding (Ingalls) report. To me, attachment 12, current testing of the washers, was most meaningful. The report notes that (internal star washer) contact area is less than a traditional (shipbuilding) bond. Nevertheless, the resistance of the system (two

Re: [PSES] CE marking - mixture of responsibilities

A NRTL tests to ALL the equipment ratings even if they include EU ratings. Rich From: John Woodgate Sent: Thursday, August 30, 2018 10:57 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] CE marking - mixture of responsibilities That's a bit dodgy, Pete. The EU product must be

Re: [PSES] Handy tip for inserting symbols in document text.

Hi Doug: Thanks. Here is a list of emoji codes to follow “U+” in Word and Outlook. I only tested one, U+2614, ☔, but I would guess they all work. I highlighted the code and then ALT x. http://www.unicode.org/L2/L2011/11438-emoji-var.pdf Best regards, Rich From:

Re: [PSES] SELV and Class III electrical protection

Hi Vincent: You asked: 1) Why is Class III electrical protection not accepted in IEC 60601-1, standard for medical device safety? According to IEC 60601-1, Annex 4: The term “Class III equipment” is used in some other standards to identify equipment that is powered from

Re: [PSES] SELV and Class III electrical protection

Hi Vincent: You asked: 3) Under what scientific basis, are the values for SELV being defined? As mentioned in my previous message, touch voltages are derived from body impedance and current. The Annexes to IEC TS 60479 series describe the research on which the body impedance

Re: [PSES] SELV and Class III electrical protection

Hi Vincent: You asked: 2) Why is there no uniform values for SELV? Example: SELV is defined as voltage not exceeds 25Vrms and 30Vrms for IEC 60601-1 and IEC 60950-1 respectively. SELV is not a voltage but a scheme for protection against electric shock. I think you are asking why

Re: [PSES] insulation between SELV and protective earthed accessible part- IEC 62052-31

Dear Mr. Vyas: I suggest you review the definitions for SELV and PELV in IEC 62052. These definitions are not the same throughout IEC standards. (I don’t have IEC 62052.) In some standards, SELV is isolated from protective earth, and PELV is connected to protective earth. If these

Re: [PSES] New Guide to the EMC Directive

“and/or” Logically, a situation cannot be both “and” and “or.” Nor can it be “and” or “or.” The use of “and/or” means the authors could not decide which alternatives are required. Poor use of the English language. Rich -

Re: [PSES] Hello

Hi Josh: I guess all of our problems are solved.  Or is it Spring Break? Rich From: Wiseman, Joshua Sent: Friday, April 13, 2018 5:21 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Hello I haven’t received any emails this

Re: [PSES] Medical device risk assessment - faulty chargers

… 2 Means of Patient Protection (dielectric and spacings requirements)… I trust this statement is a slip-up. Spacings i.e., clearances, are an indirect measure of dielectric strength. They do not constitute two independent means of patient protection. Note that creepage distances

Re: [PSES] Medical device risk assessment - faulty chargers

“… well understood risk management process provides a quite scientific and systematic method for identification of safety related issues in the construction…” I don’t agree that the risk management process “provides a scientific… method…” ISO 14971 requires identification of the

Re: [PSES] Medical device risk assessment - faulty chargers

“… does a palliative involve an interchange of energy? Yes, chemical energy. But, no injury. Rich - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a

Re: [PSES] Medical device risk assessment - faulty chargers

“Injuries to a living organism can be produced only by some energy interchange.” Not all risk are of energetic nature: Risk is never a function of energy interchange. Risk is the “combination of the probability of occurrence of harm and the severity of that harm.” Injury is a function

Re: [PSES] Medical device risk assessment - faulty chargers

… how do you test objectively the adequacy of a symbol like the ! in a triangle… The ! is not a safeguard. Ultimately, the safeguard is some prescribed behavior on the part of a person. The manufacturer of equipment can only describe the desired behavior. The behavior can be tested to

Re: [PSES] COTS system compliance

Hi Chet: Would a construction review be sufficient or is formal safety testing a must and should I involve a NRTL? Since the unit will be used in a workplace, it is subject to OSHA. In turn, Subpart S requires safety certification by a NRTL such as UL. Since all the sub-parts

Re: [PSES] Need a switch

Hi Ken: I interpret your requirement as DPDT, with 3 kV withstand between open contacts as well as 3 kV from conductors to accessible parts such as the switch lever. Tough specs. Good luck, Rich - This

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

Pete Perkins said: "Historically, the HV impulse tests applied are safety tests." Safety-wise, HV tests of safeguard insulations are to determine that the safeguard insulations will withstand the normally-occurring transient voltages that occur on the mains circuits. I wouldn't call

Re: [PSES] IEC 62368-1 3ed, Final Draft International Standard (FDIS)

I largely agree with Ted’s observations. “Most often, we need the submitter to provide more details at the meeting before the committee can make an informed decision about the proposed change.” The IEC/USTAG comment forms have limited space for comments. One MUST attend the meeting

Re: [PSES] IEC 62368-1 3ed, Final Draft International Standard (FDIS)

Hi Vincent: You asked: 1) May I know where can one has access to IEC 62368-1 3ed, Final Draft International Standard (FDIS) ? Ask your national committee to IEC TC108 for this document. 2) What are the major differences between IEC 62368-1 3ed and 2nd editions ? I don’t

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

Hi James: You asked: 1. It would makes sense to me that these powers are defined as rms power. This would be the power that causes heating over time. For instance a GSM module that takes bursts of 10W for at a 1/8 duty cycle isn’t consuming 10W, rather 1.25W. The standard does

Re: [PSES] NRTL approval

Hi Ian: In the USA (and, presumably Canada), because the supply voltage is 5 volts dc, and the power is limited to about 15 watts, I believe the unit is exempt from NRTL certification. I have a number of USB powered products (e.g., keyboard, mouse, DVD, memory sticks, etc.), some of which

Re: [PSES] Red phosphorus flame retartants

If the hype is true, and my interpretation is correct, red phosphorous as a flame-retardant additive is much better than bromine-based additives. I don’t know of cost differential. (In the two websites I looked at, there was no mention of degradation to white phosphorus.) BASF:

Re: [PSES] Brexit requirements for UK manufacturers.

Andy answered my question in posting the reference: Products that have undergone the complete process of manufacturing and conformity assessment (i.e. which are ready for placing on the market) can still be placed on the UK market with a CE Marking after 29 March 2019. Rich -

Re: [PSES] Brexit requirements for UK manufacturers.

* CE mark is replaced by UK mark. Hmm. I wonder why the UK or any country can’t recognize the CE mark as indicative of the relevant performance of the product? Rich - This message is from the IEEE

Re: [PSES] Brexit requirements for UK manufacturers.

they don’t trust manufacturer self-certification I hold a different opinion. UL was founded because the “Palace of Electricity” at the Columbian Exposition in 1893 in Chicago kept catching fire. William Henry Merrill was hired by the insurance underwriters to investigate the

Re: [PSES] Brexit requirements for UK manufacturers.

The CE mark is a first-party certification mark. It means the manufacturer believes the product complies with all applicable EU directives and has documentation to prove compliance. (The EU requires compliance to applicable directives.) Manufacturers all over the world who do

Re: [PSES] TRF Verdicts

Hi Doug: Maybe one of these documents will have the definitions you are looking for. https://www.iecee.org/documents/refdocs/ Best wishes for the holiday season, Rich From: Doug Powell Sent: Wednesday, December 12, 2018 2:29 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject:

Re: [PSES] File Attachments and the emc-pstc email list

The IEEE Product Safety Engineering Society, PSES, maintains on-line pdf files of all Product Safety Newsletters, 1988-1988, and Product Safety Engineering Newsletters, from 2006, at: http://ewh.ieee.org/soc/pses/newsletters.html Mark Montrose’ history (pdf) of the PSES is:

[PSES] holiday humor

Best wishes for the holiday season, Rich - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail

Re: [PSES] TRF Verdicts

FWIW, I was always deeply skeptical of the “(Pass, Fail, N/A)” criteria in the TRF’s because those were, and generally still are, almost totally dependent on “the eye of the beholder”, i.e. whoever does the compliance assessment! We use the terms risk, risk assessment, hazard, and safety

Re: [PSES] Glow wire tests

20:44, Richard Nute wrote: Hi John: Now that we have attachments, here it is. (I wasn’t aware that I downloaded it!) Best wishes for the holiday season, Rich - This message is from the IEEE Product Safety Engin

Re: [PSES] Glow wire tests

Hi Scott: There are some good You-Tube videos of the glow-wire test: https://www.youtube.com/watch?v=UiLdLYj1riM https://www.youtube.com/watch?v=sLCWaDIj1OU https://www.ulttc.com/en/solutions/test-methods/combustion-fire/electrical-ignition-source/gwit-en.html (animation)

Re: [PSES] Glow wire tests

Hi Scott: Sorry, but I don’t know the criteria for selecting the glow-wire temperature. Best wishes for the holiday season, Rich From: Scott Xe Sent: Tuesday, November 27, 2018 1:04 AM To: ri...@ieee.org Cc: EMC-PSTC@listserv.ieee.org Subject: Re: [PSES] Glow wire tests

[PSES] Unclear/incomplete technical specifications

* Unclear/incomplete technical specifications , link between directives essential requirements and standards technical specifications * Ambiguous test specifications, often introduced by choices a manufacturer can make on its own, so as to avoid testing. Speaking for safety

Re: [PSES] Cable Flammability Standard Comparison

Hello James: I can't point you to reading material, but I can point you to IEC 62368-1, sub-clause 6.5.1: NOTE Wire complying with UL 2556 VW-1 is considered to comply with these requirements. Also, IEC 62368-2, sub-clause 6.5.1: Rationale: Wiring flammability proposals

Re: [PSES] How to lose another million dollars

When I was working, both EMC and safety personnel worked with the designers such that both EMC and safety were done as the design progressed. EMI was suppressed at the source including judicious layout. Neither EMI nor safety was a "critical path." One division went so far as to measure and

Re: [PSES] How to lose another million dollars

“Safety is our number one priority.” How many times have you heard this? In any business, profits are the number one priority, despite the mantra. Or, in the case of the Challenger, on-schedule launch was number one priority, despite the mantra. However, the mantra is on public

Re: [PSES] Rating & WEEE markings on lithium-ion rechargeable battery

Hi Scott: I agree with John. All batteries wear out. A battery is replaceable either by the user or by a serviceman. For this reason, the battery (or the product or both) must be marked so that the battery can be replaced by an identical or equivalent battery. Same as the

Re: [PSES] Rating & WEEE markings on lithium-ion rechargeable battery

lers. If there is no marking, is it safe to replace the right battery? Do we need to take it into the risk assessment? Thanks and regards, Scott On Thu, 21 Feb 2019 at 02:53, Richard Nute mailto:ri...@ieee.org> > wrote: Hi Scott: I agree with John. All batteries wear out.

Re: [PSES] Rating & WEEE markings on lithium-ion rechargeable battery

Hi Dave: Yes. Coffee makers and other consumer electric-electronic products are not repairable by an ordinary user. If it was, a parts list would be included. When the product quits working, it is end of life. The fact that you replaced a part in a non-repairable device is

Re: [PSES] Type F receptacle wiring

Hi Doug: The French, Belgian, and Schuko domestic connectors are non-polarized. The British, North American, South Africa, some Japan domestic connectors are polarized. Some domestic connectors in Norway and many in Japan have no PE. Wikipedia discusses the various plugs and

Re: [PSES] Type F receptacle wiring

inions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-02-22 23:14, Richard Nute wrote: Hi Doug: The French, Belgian, and Schuko domestic connectors are non-polarized. The British, North American, South Africa, some Japan domesti

[PSES] human skin resistance

John referenced “skin resistance.” To my knowledge, there is no research that shows skin resistance and body resistance as separate parameters. We only know total body resistance, and that it is a variable that changes – lowers -- with applied voltage and time. Having said that, a

[PSES] CEE standards?

I'm looking for CEE standards, or a catalog of CEE standards. CEE is "Commission for Conformity Testing of Electrical Equipment." CEE was superseded by IECEE, IEC System of Conformity Assessment Schemes for Electrotechnical Equipment and Components. The standards are no longer available, but

Re: [PSES] Brexit and impact on official languages

Note that the U.S.A. does not have an “official” language, but English is predominant and is used for most government and other documents. Occasionally, someone will get a burr and propose that we adopt English as our “official” language and stop catering to non-English-language folks.

Re: [PSES] classification of the output

Hi Boštjan: Following up on my previous comment. Chances are the IEC 60990 touch current measurement scheme will not have a steady state current, but instead a fluctuating current. Especially if the PS output has a source impedance during the "off" state, which would discharge the

Re: [PSES] CEE standards?

catalogue.:-) Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-03-07 17:38, Richard Nute wrote: I'm looking for CEE standards, or a catalog of CEE standards. CEE is "Commission for Conform

Re: [PSES] classification of the output

Ted has proposed something that safety standards committees do not do: EXPERIMENTS to prove or disprove the requirements. But I have done voltage, current, and thermal experiments on students (voluntarily) at the Energy Class 1 levels in my HBSE courses. One of the more

Re: [PSES] classification of the output

Hi Mick: In 1961, James J. Gibson published a paper entitled “The contribution of experimental psychology to the formulation of the problem of safety: a brief for basic research.” This paper reported his studies of injury causation in automobile accidents: “Injuries to a living

Re: [PSES] CEE standards?

/refdocs/ Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-03-07 19:18, Richard Nute wrote: Hi John: I asked IEC. No response. Best regards, Rich From: John Woodgate <

Re: [PSES] AW: [PSES] Source for Nameplate Rating Nomenclature

Hi Brian: We have three standards, one for the manual, and two for the product (the product standard and the general standard, IEC 61293). The mains ratings display differ among the standards. Your products must adhere to the product standard. If no marking requirements are in

Re: [PSES] Johnson City NY - crazy street lights

Hi Doug: “… DMX512 is not two-way communications as such and would not be able to report a defective fixture needing maintenance…” Where I live, the street lights are controlled individually by light sensors. When a light burns out, we residents report it to the city (feedback

Re: [PSES] Johnson City NY - crazy street lights

Hi Doug: Each individual light is blinking at its own pace. You can see this by pausing the video; at each pause, some lights are on, while some are off. (At first, I thought they were blinking in sequence, but you can see that this is not the case by pausing the video at different

Re: [PSES] Tamper-proof Hardware

To: Rich Nute Cc: IEEE EMC PSTC Subject: Re: [PSES] Tamper-proof Hardware Rich, Respectfully, I have to disagree. ISO 14119, Safety of machinery — Interlocking devices associated with guards — Principles for design and selection, specifically addresses defeat resistance in interlocking devices

Re: [PSES] Tamper-proof Hardware

Standards need not – indeed should not -- address nefarious activity on the part of the user. And, standards need not address tampering (defined previously) as there can be no end to the extent of tampering. The requirement for “tamperproof” is beyond the scope of safeguarding a user

Re: [PSES] Tamper-proof Hardware

carried out. Best wishes John Woodgate OOO-Own Opinions Only J M Woodgate and Associates www.woodjohn.uk <http://www.woodjohn.uk> Rayleigh, Essex UK On 2019-04-09 19:04, Richard Nute wrote: Standards need not – indeed should not -- address nefarious activity on the part of th

Re: [PSES] Tamper-proof Hardware

In IEC 62368-1, Basic Safeguards provide protection under normal conditions. Supplemental Safeguards provide protection under fault conditions, including a fault of the Basic Safeguard. Supplemental Safeguards ARE required. I have seen folks who say that the standards represent

Re: [PSES] Tamper-proof Hardware

>From dictionary.com: tamperproof adjective 1 that cannot be tampered with; impervious to tampering tamper verb (used without object) 1 to meddle, especially for the purpose of altering, damaging, or misusing (usually followed by with ) 2 to make changes in something, especially

Re: [PSES] classification of the output

Hi Boštjan: If you say ES1 and another certification body says ES2, then a negotiation must take place. To avoid negotiation, you must change your verdict to ES2. However, the manufacturer wants ES1, which is determined by the voltage. I agree that the voltage waveform is ES1

Re: [PSES] 62368-1 Openings in a fire enclosure

Hmm. Interesting English usage statement. If something fills an opening, the opening no longer exists. So, how do you know how to apply the requirement? Rich From: Payne, Glyn <0d283c0acebb-dmarc-requ...@ieee.org> Sent: Friday, May 17, 2019 6:40 AM To:

Re: [PSES] 62368-1 Openings in a fire enclosure

combustible material so according to the standard it’s V-1! I’m sure the interpretation will vary between different facilities and it’s still early days for application of 62368-1. Best regards, Glyn From: Richard Nute mailto:ri...@ieee.org> > Reply-To: mailto:ri...@ieee.org&g

Re: [PSES] Stacking Grounds on a Stud

Hi Brian: As you know, my opinions are engineering-based, not standards-based. The rule (or principle) is that the main protective grounding (of the power cord) need not be disturbed when servicing the other stacked ground circuits or assemblies on a stud or stud-equivalent. This

Re: [PSES] Grounding

Hi Steve: I disagree with my colleagues. You didn’t say how the mains was distributed from the first module to the second and third modules. I have assumed the mains is also distributed by the Wago/Din rail scheme. If this is the case, then I would say the grounding can also be

Re: [PSES] Tilt test

Hmm. * The equipment is tilted in all directions such that the base of the equipment is at an angle up to and including 10°; or Only one direction is significant: The side of the base that is closest to the center of gravity. This is the worst case. If the equipment passes this

Re: [PSES] 62368-1 Openings in a fire enclosure

Hi Glyn: You have the option of testing the bulkhead connectors in place (Annex S.1). Apply the test flame to the inside surface of the installed connector material at a point judged to be likely to become ignited because of its proximity to a source of ignition. I suspect your product

Re: [PSES] GB or GC?....that is the question....

Hi Regan and all: As I’m sure you know by now, I subscribe to engineering principles, not to the various safety standards. Some years ago, I did some tests to determine the better production-line test for the grounding circuit. I documented my findings in an article in the Product

Re: [PSES] GB or GC?....that is the question....

at the facts another way. Since the test is passed, provided the fault does not get worse, the product remains safe. It's not an ideal situation, but it seems that something like a 100 A test would be required in order to detect a fault of either type described. On 2019-05-22 17:28, Richard Nute

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

Yes, EMC and safety must be designed in. It follows that the person who designed it in must also be able to predict the test outcome. If the test outcome is not as predicted, either the test was wrong or the prediction was wrong. In my experience (safety), the test house would like

Re: [PSES] Tilt stability and CoG test lab

Hi Frank: In most cases, the COG is near or at the geographic center of the equipment.  This would be at the half-way point of each dimension, W, L, H.  For your product, the worst-case tip-over would be on the W (5 feet) side. Expanding on Doug's suggestion, tip the unit on each bottom

Re: [PSES] Guidelines v Standards v Codes

Hi Doug: Way back when, Dwaine Richins, professor at University of Oregon, taught that a standard was “a statement of acceptable performance.” Keeping this definition in mind… Laws enable a government agency to generate regulations, codes, or even standards. An electrical code is a

[PSES] test message

I had to reinstall my e-mail app, so this is a test whether I set it up so I can post to the listserver. Rich - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to

Re: [PSES] Ground on ship

Hi Bill: On 7/13/2019 10:42 AM, Bill Owsley wrote: They started out, and still in some rural areas, use earth as the "ground" for the return of the AC power being provided to users. The descriptive term is "SWER,"  Single Wire Earth Return.

Re: [PSES] Ground on ship

Hi Peter: Sea water is a very good conductor, better than soil.  Fresh water is an okay conductor.  Pure water is a poor conductor. The hull of a steel ship is well grounded in the ocean, and reasonably well grounded in fresh water due to the large contact area with the water. If the hull

Re: [PSES] Ground on ship

For us safety nerds, grounding provides an equipotential environment, which means no current through the body.  And, the grounding circuit provides a return path for fault current.  We don't pay attention to Gnd0, Gnd1, Gnd2, Gnd-Iso, etc.; for safety purposes, they are all at the same

Re: [PSES] Branding Products and EU Decision 768 NLF

Hi The Other Brian: “Company-A's name and address is on the Nameplate Label on the back of the Widget. Company-A handles everything including the Conformity Assessment, Generating the EU-DoC, Applying the CE marking, audits, inspections, etc..” All of the other markings and stuff

[PSES] committee member motivations

Regarding the standards... standards are written by guys like you and me. Experts in the WG and national committees are not paid for their knowledge (which actually is one of the finest on the planet !) , and many of them will confirm that they (or their employer) actually need to pay to

[PSES] Do We Need Flame Retardants in Electronics?

https://www.scientificamerican.com/article/do-we-need-flame-retardants-in-el ectronics/ ".there has never been any valid statistical demonstration that flame retardant chemicals of the types and concentrations used in consumer products have resulted in death or injury reduction," says Vytenis

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

of illness and injury from the chemicals themselves and disposal of the products. Rich On Mon, Sep 16, 2019 at 2:32 PM Richard Nute mailto:ri...@bendbroadband.com> > wrote: <https://www.scientificamerican.com/article/do-we-need-flame-retardants-in-electronics/

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

jority has supplied such data. As general source of reference to identify substances typically used as flame-retardants I recommend the IEC 62474 Declarable Substance List at http://std.iec.ch/iec62474. Kind regards, Bernd Von: Richard Nute Gesendet: Dienstag, 17. September 2019 01:00 An

Re: [PSES] Product safety leading edge

r. 10. New concepts in medical products. Best regards, Richard Nute IEEE Life Fellow Bend, Oregon, USA On 7/26/2019 7:13 AM, David Schaefer wrote: All, As an EMC engineer I’m aware of new technologies and challenges in EMC testing - 5G and IoT, time domain measurements, risk management,

Re: [PSES] UL 61010-1 7.4 stabilty

Hi Doug: See IEC 61010, 3rd edition, Clause 7.4 d) and e). The 4X load is only applied to the support or castor that has the greatest load (independent of the equipment) (d).  I guess the pass criterion is no failure of the support or castor.  (If the support or castor is rated 4X or more

Re: [PSES] IEC 61010-1 & leakage current

Hi Chet: IEC 61010 doesn't use the term "leakage current" (or the IEC 60990 term "touch current.")  Instead, it uses "hazardous live."  The values are in 6.3.1 and 6.3.2.  These same values are valid for the USA and Canada (because there are no national differences for North America).  Note

[PSES] fire enclosure requirements for small Lithium battery

"Many manufacturers consider outer tape around battery, that's meet min. V-1, as fire enclosure." This construction may meet the letter of the standard, but is not effective as a fire enclosure. If the battery overheats, it will melt the tape and. Best regards, Rich -

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

ood therefore bad practice. Thanx for bring this around again. :>) br, Pete Peter E Perkins, PE Principal Product Safety & Regulatory Affairs Consultant PO Box 1067 Albany, Ore 97321-0413 503/452-1201 IEEE Life Fellow <mailto:p.perk...@ieee.org> p.perk...

[PSES] FCC regulatory statements

“This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation” Hmm.

[PSES] The Consumer Electronics Hall of Fame: BRK First Alert Smoke Alarm

GbVptSXhOekZpWWpOayIsInQiOiJ0T3dTaTdXTUFMeWNXK0ZJOXhwNlF4ZkgxT0JPNWN1UXhzV1B 1TmVoNWVFR2FCMVFHNk1TbVlrcDR4Y2lFa0M3ZTJ1WFFxdkJwOElmaW44cVlCTmtka0lIWHZ0XC9 cL0JlMmlGT0VJZGZHRWtmMDBOUnRlT3BpYjVSaTBjNW9UdFoyIn0%3D Best regards, Richard Nute Bend, Oregon

[PSES] Why China Is Dominating Lithium-Ion Battery Production

https://www.forbes.com/sites/rrapier/2019/08/04/why-china-is-dominating-lith ium-ion-battery-production/#2b9d77883786 "According to the research organization BloombergNEF, the volume weighted average lithium-ion battery pack price (which includes the cell and

Re: [PSES] Fire enclosure IEC/EN61010 - flammability classification

Hi Amund: Yes. See IEC 61010-1 2010, 9.3.2 c) 2). Best regards, Rich From: Amund Westin Sent: Monday, December 9, 2019 3:46 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Fire enclosure IEC/EN61010 - flammability classification * Moveable equipment (4 pcs

Re: [PSES] EN 61010-1 accessible Energy Hazard

Hi Charlie: Is there a clause/requirement in 61010-1 similar to 60950-1 clause 2.1.1.5 where a SELV source >240 VA is not permitted to be accessible in an Operator Area I could not find this requirement in 61010-1, 3rd edition. The 240 VA requirement does not insure safety due

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