Re: [PSES] Meet some of the list admins at the PSES Symposium next week

I'm sure we all agree that NO failures is the goal, but to John's point, I think it would be instructive for some to know what types of failures are generally found. (e.g. marking, ventilation openings, temperature limits, dielectric strength, ground bonding, critical components, clause

Re: [PSES] SV: [PSES] Residual-Current Device

It's a programmable device, so the code which runs it could serve a safety critical function and some standards would then refer to UL1998 or perhaps IEC 61508-1. I don't think 60950 has yet taken that "leap". Ralph McDiarmid Compliance Engineering Residential/Commercial Solar Business

Re: [PSES] IEC60950-1, Table 2N - creepage

I have long wondered why solder resist on a PCB cannot be used to reduce pollution degree and therefore creepage distance. Ever try to scrap it off? I am sure that all product standards today, assume bare FR4 material with no coating (no solder resist). I know that IEC60664 calls out a bunch

Re: [PSES] A quote from Tim Kelly, University of York

A good summary of the state of affairs I think. The last few decades of independent standards development around the world seems to have produced a wide variety of non-harmonized requirements. Perhaps things are slowly improving with wider adoption of IEC standards for safety and for EMC.

Re: [PSES] Commom mode current vs. differential mode current and LISN

A few years ago, I witnessed an electrician shorting 600/347V bus to an grounded metal duct with his screwdriver. A shower of sparks and then darkness after the 600V breaker for the entire building tripped. I was surprised he stayed on the ladder. Ralph McDiarmid Compliance Engineering

Re: [PSES] "For indoor use only" on External Power Supply

I must admit I didn't understand any of that, other than references to MTBF and HALT. It just seems to me that RA is akin to FMEA and FTA (Fault Tree Analysis) efforts, namely, it's just guess work. There is no way to come up with a number that can relied on, since there are too many

Re: [PSES] Commom mode current vs. differential mode current and LISN

And to keep things interesting, WG8 of TC77A is trying to define conducted emission limits between 9kHz and 150kHz. (I think in response to industry segment responsible for smart wattmeters and other PLC devices communicating on LV mains) Ralph McDiarmid Compliance Engineering

Re: [PSES] Standards for Photo Voltaics Inverter

IEC 62109-1 and 62109-2 (at least that's what we are using here for Europe and Australia) For USA it would be UL1741, and UL62109-1) Ralph McDiarmid Compliance Engineering Residential/Commercial Solar Business Schneider Electric 3700 Gilmore Way Burnaby BC Canada From: Grace Lin

Re: [PSES] Insulation testing

Some say 0th fault to mean it is expected to fail, therefore you fault it, before applying a single-fault. Not the best terminology perhaps. If bonding impedance test passes, then the circuit is not functional earthed, it is bonded to earth (to the equipment grounding conductor), In that

Re: [PSES] Insulation testing

resending (1st one bounced) From: Ralph McDiarmid/Canada/Schneider To: EMC-PSTC@LISTSERV.IEEE.ORG, Date: 02/25/2016 08:51 AM Subject: Re: [PSES] Insulation testing It seems that the standards are treating functional ground connections (those that do not pass a bonding impedance test) as a

Re: [PSES] Reliable means to attach thermocouple to object

However, it is easier to just measure it than argue with the NRTL, which must follow what the standard says, which all too often include semiconductors and capacitors. Some of the tables in standards like UL458 haven't been updated for a long time. (when was the last time you saw a selenium

Re: [PSES] Reliable means to attach thermocouple to object

We use a small drop of gap-filling cyanoacrylate (like Krazy Glue) to affix thermocouples. With strain relief (taping) they stay put up to 160C in our experience. That glue type is nice because it is easy to see bead contact with the surface. . Ralph McDiarmid Compliance Engineering

Re: [PSES] Spectrum analyzer and noise floor

I would like to explain to a colleague why the noise floor on a SA does not look flat as it sweeps across a given frequency range after antenna factors, cable factors, external gain and external attenuation are programmed into its display function. I think it breaks down to these fundamental

Re: [PSES] Ancillary Equipment per EN 301 489-1

If it helps, the Oxford Concise English dictionary defines "ancillary" as: "a person, activity, or service providing essential support" Since the AC/DC adapter is essential to the function of the device, it provides more than merely "essential support" It is by all means an inseparable part of

Re: [PSES] [EXTERNAL] [PSES] AU CISPR 22 Class B Interpretation

And, for another perspective, UNECE Regulation 10, "Uniform provisions concerning the approval of vehicles with regard to electromagnetic compatibility", restricts 10m radiated emissions to limits which lie between CISPR Class A and Class B. Ralph McDiarmid Compliance Engineering

Re: [PSES] Fwd: [PSES] Current probe for CM currents

" I have been experimenting with this and in several cases using a ferrite clamp at the end of cabling seems to "stabilize the spectrum", increasing low peaks and reducing high peaks. " Seems to me that it's akin to adding resistance to an L-C network to provide better damping. So, these

Re: [PSES] Current probe for CM currents

Would a Near Field probe be a better choice? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Ken Javor To:

Re: [PSES] spacex EMC tst engr job

I though this funny that one of the preferred skills is, "Able to type at a rate of at least 50 wpm" I think my mom could do 60 wpm in about 1950 on a manual typewriter. I think I can do about 40 wpm on a good day on a keyboard; 50 would be take some training and dedication.

Re: [PSES] Looking for a good 30 kVA source

It looks like their Triathlon II models cover a full range of power ratings. http://www.georator.com/ProductAdjustableFrequencyConverters.html ___ Ralph McDiarmid | Schneider Electric | Solar Business |

Re: [PSES] EN 55035/CISPR35

Australia has a similar constraint. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Bill Owsley <00f5a03f18eb-dmarc-requ...@ieee.org>

Re: [PSES] CISPR11 Ed 6 (FDIS)

Dear group, CISPR11 Ed 6 (currently in FDIS) has added emission limits for DC ports, including PV and Battery. For products which have DC power ports and which have up to now used the generic EMC emissions standard, would a change to CISPR11 (EN55011) to now include DC ports make it the

Re: [PSES] Relays and Contactors

I assume the relay would have to meet double/reinforced open contact spacing and dielectric strength in this application. Correct? Sounds right We are having a hard time finding a relay that specifies an open contact dielectric strength for double/reinforced (3000Vac or 4200Vdc). How about

Re: [PSES] Internal connection labels in 220VAC systems

Ask him to reference a clause in an applicable standard. Do you know if spacings from N to PE circuit and to dead metal have been evaluated for 240V ? (in the event it gets cross wired during installation) ___

Re: [PSES] EN55032 definition of residential environment

I'll only add that the descriptions and examples in the 61000 generics are pretty clear. Like everything else with EMC, there are shades of grey. ___ Ralph McDiarmid | Schneider Electric | Solar Business |

Re: [PSES] EN55032 definition of residential environment

Agreed ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: John Allen To: EMC-PSTC@LISTSERV.IEEE.ORG, Date:

Re: [PSES] size of protective bonding conductor

I expect they would come from a national electrical code. If this is a UL standard, then the NFPA 70 (NEC) ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance

Re: [PSES] size of protective bonding conductor

les list primarily mm sq sizes. “AWG and kcmil sizes are provided for information only.” So not likely these are NEC based. But don’t know the answer to the original question. Perhaps NFPA 70 has table that goes larger but may not help outside of US. -Dave From: McDiarmid, Ralph [mail

Re: [PSES] size of protective bonding conductor

onding conductor Take a look at Table 250.122 in the National Electrical Code. Best regards, Ron Wellman From: McDiarmid, Ralph [mailto:ralph.mcdiar...@schneider-electric.com] Sent: Wednesday, November 25, 2015 3:19 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] size of protecti

Re: [PSES] 208 split-phase?

Most residential high-rise buildings distribute 120/208V throughout the building. Electric ranges and dryers will run from 120/208V or 120/240V ___ Ralph McDiarmid | Schneider Electric | Solar Business |

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

Isn't that the risk for any measurement using a SA, particularly when measuring from an AMN? (peak, QP or AVG) ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

I can see how adding gain ahead of the SA lowers the noise floor, but I don't see how a preselector can do same. A preselector seems most useful in tuning only the frequency band of interest, rejecting (attenuating) the rest.

Re: [PSES] 208 split-phase?

chneider-electric.com" <ralph.mcdiar...@schneider-electric.com>, "EMC-PSTC@LISTSERV.IEEE.ORG" <EMC-PSTC@LISTSERV.IEEE.ORG>, Date: 10/22/2015 02:32 PM Subject: RE: [PSES] 208 split-phase? I believe NFPA 70 specifies 120/240V for all residential household voltages. -Da

Re: [PSES] Preselector requirement in ANSIC63.4 -low PRF

Exactly the procedure I posted in our EMC lab years ago. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: "Kunde, Brian"

Re: [PSES] QP Dectector - how to confirm accuracy & functionality

Pulse duty ratio must be important too. I've often seen Pk measurements 5 or 6dB higher than QP. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering

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

Hi Ken, I just scanned through that EDN article. I see from your graphic that the measurement time was 100ms, so I'm assuming Peak detection. (not quasi-peak or average) Depending on the nature of the signal, I assume it might be quite a bit lower when using an average detector. When I do

Re: [PSES] Unexplained High Fallout of Power Supplies

>This lab area has surge protection, so again, we believe the problem is some kind of low voltage transient, voltage dropout, or >waveform distortion that we have been unable to detect and simulate. Was it tested against IEC 61000-4-11 (voltage dips, short interruptions, variations ) ?

Re: [PSES] Unexplained High Fallout of Power Supplies

I recall that PFC circuits are generally based on a boost converter and that circuit arrangement if often challenging to tune for stable closed-loop response. I think PFC applications try to regulate both input current and output voltage; one is tightly regulated, the other is not.

Re: [PSES] UL CSDS website

Anyone having trouble logging into that site today? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering -

Re: [PSES] requirement for spacings

Clause 5.2.3 in EN50178 (Decisive Voltage) should help clarify. It writes about "occurs continuously" and "worst operating condition". I don't think UL508 will be much help, unless it allows use of UL840 (insulation coordination) as an alternate approach to spacings.

Re: [PSES] IEEE Electromagnetic Compatibility magazine

If I could download the entire October 2015 issue, it looks like it would be 100MB. I wonder if they split it into many, smaller chucks for that reason, because their server has a relatively slow upload data rate? It took me 30s to download the single-page table of contents.

Re: [PSES] Different surge test equipment, different results

Thanks David for bringing that detail into focus. Edition 2 writes about unwanted voltage drops from coupling/decoupling networks, while Table 6 allows for a shorter front time for higher line currents, presumably to reduces impedance required by the decoupling network ( a smaller

Re: [PSES] rapid shut down requirement for solar inverter

And there are going to be more stringent requirements in the 2017 NEC, related to rapid shutdown. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering

Re: [PSES] Optos for PELV isolation

Like very low-drift analog circuits, high impedance circuits require attention to detail normally dismissed as negligible in 'everyday' circuit design. ___ Ralph McDiarmid | Schneider Electric | Solar Business

Re: [PSES] Australia/New Zealands mains voltage

Could you mark it 220/230/240V ? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Scott Xe scott...@gmail.com To:

Re: [PSES] Calculating Reflection Angles on OATS/SAC

If it helps, the EMC Handbook Vol. 4 (White) suggests that absorbing material (6dB loss) in an SAC reduces the error caused by all reflection (reinforced/cancellation) to about 4dB peak to peak. Single bound path with no absorption seems to result in only about 3dB (peak to peak) error,

Re: [PSES] GFCI Nuisance Tripping

See the less well-known CISPR 17 standard. Or, any decent text book on a.c. circuits. The reason I still have some of my aging, but still useful, college text books. ___ Ralph McDiarmid | Schneider Electric |

Re: [PSES] WiFi consultant needed

We are looking for an EMC consultant or an EMC lab with a good knowledge of international requirements for certifying host products to which an approved WiFi transceiver module has been added. We know the basics for the US, Canada, and the EU but need help for a long list of countries outside

Re: [PSES] leakage current tests

IEC 60335-1 13 Leakage current and electric strength at operating temperature Protective Impedance and radio interference filters are to be disconnected before carrying out the tests. I suppose they are merely checking for an obvious no-no, like using accessible chassis metalwork as a

Re: [PSES] CISPR 32 adoption

Maybe I'm missing something, and I'm certainly no statistician, but on page 11, it states, A manufacturer, knowing the typical standard deviation of RFI measurements on his products, can – using the 80%/80% rule - estimate the required margin to the limit already with a single prototype.

Re: [PSES] Is NRTL listing mandatory for consumer-grade telephone terminal equipment?

I'm drifting ever so slightly off topic now but . . . legislation certainly keeps NRTLs in business. I've long admired the EU model, where manufactures declare compliance and are responsible for it. Do we really need 3rd party certification in USA, Canada, Australia, etc? I think the new

Re: [PSES] ISO17025 calibration lab

Can anyone recommend a calibration lab for current tranducers rated to 3,000A (ac and dc) to ISO17025 with a certificate? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory

Re: [PSES] How cops are catching grow ops with AM radios.

Now that the cat's out of the bag, the grow ops will quickly become EMC experts. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Ken Wyatt

Re: [PSES] How cops are catching grow ops with AM radios.

The overhead wires for the electric trams (buses) here cause strong RFI on fringe stations on the AM band, but not strong enough to interfere with local broadcasts. ___ Ralph McDiarmid | Schneider Electric |

Re: [PSES] question with regard of inverter

, August 08, 2014 3:47 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] question with regard of inverter IEC 62109-1 considers “PV circuits in general” to be OVCII. Regards, Peter Tarver From: McDiarmid, Ralph [mailto:ralph.mcdiar...@schneider-electric.com] Sent: Friday, August 08, 2014 13

Re: [PSES] question with regard of inverter

My understanding as well, namely, OV categorization in power distribution is based on indirect (near-by) lightning strikes. ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory

Re: [PSES] Definition of unsafe product

Certainly appears that they did. As I understand it, the DofC doesn't even need to accompany the product, only that the product bear the CE mark. ___ Ralph McDiarmid | Schneider Electric | Solar Business |

Re: [PSES] E-Labelling?

Do you mean the e-mark or the E-mark? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering Phone: +1-604-422-2622 | Address: 3700 Gilmore Way, Burnaby,

Re: [PSES] Anti-islanding relay

And IEEE1547 doesn't required a disconnection for unintentional islanding, merely that the DG ceases to energize the local electrical power system. (stop a negative power flow from the DG) Some utilities in the USA and in Canada are suggesting that 500ms is a better response time, to

Re: [PSES] radiated emissions testing may understate actual emissions, an example using a class D stereo amp

Linear techniques these days are costly, heavy or just unfashionable. Or mysterious to some of the recent graduate engineers today? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA |

Re: [PSES] question - emission measurements below 150kHz

Dear EMC-PSTC forum members, Given a need to measure conducted emissions from 150kHz down to 9kHz, would it be better to: 1. characterise 50ohm LISN for insertion loss down to 9kHz 2. use a current clamp rated for that frequency and use transfer impedance to determine dB(uV) I can see that

Re: [PSES] Wire ampacities -

. . . or wire in free air, or buried, depending on what table you look at. As as gut feel, I would say that 3 inches of 26AWG would have a very low temperature rise at 500mA, but as John stated, it's best to run a test.

Re: [PSES] California Prop 65

Californians ? ___ Ralph McDiarmid | Schneider Electric | Solar Business | CANADA | Regulatory Compliance Engineering From: Ed Price edpr...@cox.net To: EMC-PSTC@LISTSERV.IEEE.ORG, Date: 07/11/2013