2001 RMCEMC Symposium Advance Notice

[ChasGrasso]

To all interested parties
(especially those who could not get
to Montreal!!)

The Rocky Mountain Chapter (RMC) of the Institute of Electrical and Electronic 
Engineers (IEEE) Electromagnetic Compatibility (EMC) Society will hold its 11th 
annual Regional EMC Symposium on Wednesday, October 3rd, 2001 at the Radisson 
Inn Greystone Castle, North Denver, Colorado. The annual symposium is a key 
element of the Chapter program, which is focused on providing the regional 
technical community with valuable EMC training and education. This year we are 
pleased to further expand our technical program to provide multiple technical 
tracks including:
¨ Full day Tutorial on Fundamentals of EMC by Dr Clayton Paul. Dr Paul is the 
author of 12 textbooks on electrical engineering subjects, and has published 
over 200 technical papers, the majority of which are in his primary research 
area of electromagnetic compatibility (EMC) of electronic systems in EMC.
¨ Technical papers on current topics by regional and national authors
¨ Workshop sessions exploring selected topics presented by experts in the EMC 
field.
¨ Exhibits of products and services related to EMC, including many 
international firms. 

The quality of the technical program at the RMC EMC has always been exceptional 
thanks to the local EMC community. The expanded program provides more 
opportunities for continuing education in EMC. With multiple tracks, you may 
not be able to attend every session, so please invite your associates with an 
interest in EMC – the program is open to everyone with an interest in the 
field, you do not need to be an IEEE member 

Even with the expanded program, we have been able to keep the program very 
affordable – and include meals so you will not need to miss any of the 
technical program. We encourage you to register early – this will help us 
plan the event and can provide reduced registration for you. 

Please help spread the word about this affordable education opportunity. 

Thank you
Charles Grasso



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Re: EN61800-3:1996 Specification

[John Woodgate]

I read in !emc-pstc that Hart, Michael  wrote (in
<9efd49e2fb59d411aaba0008c7e675c004a41...@emss04m10.ems.lmco.com>) about
'EN61800-3:1996 Specification', on Tue, 28 Aug 2001:
>With respect to the immunity requirements, can someone please tell me what
>immunity tests (radiated immunity, ESD, EFT, etc.) are associated with the
>standard and a brief table showing the requirements (frequency ranges,
>levels, etc.)?
>
>With respect to the emissions requirements, can someone please tell me what
>the limit levels are (including units) and the frequency range evaluated?
>
>Confirming that the EN61800 requirements are similar to the EN55024
>requirements would be very helpful as well.

While a hobbyist might reasonably ask for detailed information about the
content of standards, your organization has no reason not to buy them.
It is very risky to rely on someone's paraphrase or abstraction from
standards: there are notes and cross-references that can put a specific
and counter-intuitive meaning on to some texts. Posting accurate and
extensive paraphrases is also a copyright violation, of course.
-- 
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk 
Eat mink and be dreary!

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Re: EN61000-3-2,3

[John Woodgate]

I read in !emc-pstc that William D'Orazio  wrote (in
<1c89780c4179d3118c580090277193580fbcc...@caemsx01.cae.ca>) about
'EN61000-3-2,3', on Tue, 28 Aug 2001:

>My understanding of EN61000-3-2,3 is that they are applicable to the
>power input terminals of equipment intended to be connected to systems with
>240/415-250/430V operating at 50-60Hz.  Therefore if 480 V is supplied to a
>building, with a local transformer to step the voltage down to 400V, is the
>equipment operating within the building exempt from these standards.

That situation simply does not occur AFAIK. But if it did occur, the
standards might not apply, but that is far from certain. Not that you
are likely to be able to buy equipment that doesn't conform at present,
designed exclusively for use in the situation you describe.

>  What
>if the HV transformer that steps down HV-480V supplies other buildings as
>well, are we still exempt from the requirements of this standard.

It is true that the standards apply only to **public LV supplies**. If
you have a site with its own MV or HV/LV transformer (not a 480/400 V
transformer, which is LV/LV), **not supplying any other customer of the
utility**, then you have private LV supply and you only need to meet
IEC/EN61000-3-6 guidelines at the MV or HV terminals.
-- 
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk 
Eat mink and be dreary!

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August, 2001 EMC/Telco/Product Safety Update Now Available

[Glen Dash]

The Curtis-Straus Update is for August, 2001 is now available at:

http://www.conformity-update.com

The headlines are:

Reprieve: You Can Use EN 55022:1994 For Two More Years. 

UK: Even EN 55022:1998 Is Not Tough Enough. 

New Standards For The EMC And R&TTE Directives. 

The FCC Officially Out Of Part 68 Registration Business. 

Part 68's Administrative Council Up And Running. 

FDA Proposes Harmonizing Its Laser Standard With IEC. 

FDA Recognizes ANSI/ESD S20.20. 

IEEE Pilot Program Provides Free Access To Networking Standards. 

EU: Protection From EMF Is A Fundamental Right. 

Standards Update. 

Meetings and Seminars.

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ETSI dimensions

[Dave Wilson]

Does anyone have a feel for how close the spacing requirements in ETS 300
119 have to be met? There doesn't seem to be any tolerances, mins or maxes,
i.e. the implication is that all dimensions must be met exactly.

Anyone fallen down in Europe over this? Also, in ETS 300 119-4 it seems that
D1 is incorrectly marked, i.e. D1 should be the entire depth, not the front
part.

Thanks in advance,

Dave Wilson
Alidian Networks

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EN61800-3:1996 Specification

[Hart, Michael]

I currently have a motor controller from an outside vendor which lists
compliance to the EN61800-3:1996 requirements.  I'm attempting to correlate
the frequency ranges evaluated and the applicable limits tested under
EN61800-3 to the equivalent MIL-STD-461 requirements.  

According to the manufacturer the environments selected were as follows:

Immunity:
Second environment (Industrial environment)

Emissions:
First environment (Domestic environment)

With respect to the immunity requirements, can someone please tell me what
immunity tests (radiated immunity, ESD, EFT, etc.) are associated with the
standard and a brief table showing the requirements (frequency ranges,
levels, etc.)?

With respect to the emissions requirements, can someone please tell me what
the limit levels are (including units) and the frequency range evaluated?

Confirming that the EN61800 requirements are similar to the EN55024
requirements would be very helpful as well.

Regards,

Michael

EMI/EMC Sr. Systems Engineer
Lockheed Martin
Naval Electronics & Surveillance Systems
P.O. Box 4840, EP5-D5, MD45
Syracuse, New York 13221
Email: michael.h...@lmco.com  

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Re: Burn-in methods

[Doug McKean]

Just to add to what others have said, I was assuming single 
no redundancy failure mode.  If the product being tested 
has  m-of-n redundancy, things get very complicated 
very quickly. 

In other words, if a shelf of 8 modules can continue 
to run after 2 of the modules fail, that product has a 
6-of-8 redundancy. 

For topics in redundancy and general reliability calculations, 
take a careful look at the following NASA website ... 
 http://tkurtz.grc.nasa.gov/srqa/dfr/dfr6.pdf 

It has some great information. 

Also is  
  http://www.cs.colostate.edu/~cs530/7reliability.pdf 

- Doug McKean 



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RE: Susceptibility level of medical devices (incubator) - urgent!

[Ned Devine]

Hi,

Per the FDA guidance on EMC http://www.fda.gov/cdrh/ode/638.pdf
The limit is 3 V/m.  See the page numbered 25 of the document.

Note:  This is for general medical equipment!  There is a guidance document
for incubators http://www.fda.gov/cdrh/ode/incubator.html
It references IEC 60601-2-19 and 2-20.  2-19 and 2-20 both require the unit
to pass at 3 V/m and to pass or fail safe at 10 V/m.  


Ned Devine
Program Manager III
Entela, Inc.
3033 Madison Ave. SE
Grand Rapids, MI  49548

616 248 9671 Phone
616 574 9752 Fax
ndev...@entela.com  e-mail






-Original Message-
From: Ralph Cameron [mailto:ral...@igs.net]
Sent: Monday, August 27, 2001 5:33 PM
To: Antonio Sarolic; emc-p...@majordomo.ieee.org
Subject: Re: Susceptibility level of medical devices (incubator) - urgent!



Antonio:

I would say many incubators were manufactured when there were no concerns
and the susceptibility was a function of the design and very variable. I
have heard they vary from 0.1V/m to 10V/m but don't think there is any set
standard. The medical gurus prefer to isolate their equipment by physical
barriers and hope that something will not affect them

In Canada Health Canada could answer thequestion . In the U.S. I believe its
the Food and Drug Administration.

Ralph Cameron
EMC Consulting and Suppression of Consumer Electronics
(After sale).


- Original Message -
From: "Antonio Sarolic" 
To: 
Sent: Monday, August 27, 2001 11:59 AM
Subject: Susceptibility level of medical devices (incubator) - urgent!


>
> Hi
>
> I need urgent info on susceptibility level of medical electronic devices,
> especially baby incubators. Can anyone confirm if it is 1V/m (according to
> EU standards)? The EMI source is the GSM BS antenna (900MHz).
>
> Thanks very much.
> Antonio
>
> Antonio Sarolic, M.S.E.E.
> Faculty of Electrical Engineering and Computing
> Dept. of Radiocommunications and Microwave Engineering
> Unska 3, HR-1 Zagreb, CROATIA
> tel. +385 1 61 29 789, fax. +385 1 61 29 717
> E-mail: antonio.saro...@fer.hr
>
>
>
>
> ---
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EN61000-3-2,3

[William D'Orazio]

Gents,

My understanding of EN61000-3-2,3 is that they are applicable to the
power input terminals of equipment intended to be connected to systems with
240/415-250/430V operating at 50-60Hz.  Therefore if 480 V is supplied to a
building, with a local transformer to step the voltage down to 400V, is the
equipment operating within the building exempt from these standards.  What
if the HV transformer that steps down HV-480V supplies other buildings as
well, are we still exempt from the requirements of this standard.

Thanks in advance,
Regards,  


William D'Orazio 
CAE Inc.
Electrical System Designer

Phone: (514) 341-2000 (X4555)
Fax: (514)340-5552
Email: dora...@cae.ca




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Burn-in methods

[georgea]

First, I am no expert on accelerated life testing.  However,
I do know that life testing depends a good deal on the nature
of the product.  In other words, how will it be used, how often
will it be used, and what are its failure modes?

An electric pencil sharpener may be used only five to ten times
a day for about five seconds each time, and has as much mechanical
content as electrical content.  An electronic control system may
have no mechanical failure modes, but run continuously (24/7).

I do recall from the early days of solid state electronics that
there were three principle aging factors: (1) on-off cycles,
(2) power on hours, and (3) calendar hours.  On-off cycles
cause heat expansion/contraction at all of the electrical
interfaces (e.g. solder joints) that lead to stress fractures
due to differing thermal coefficients of expansion in the joint
materials. Power on hours "age" the solid state junctions at a
temperature dependent rate (each 10oC halves the lifetime).
The "calendar" age of the electronics, whether ever powered on
or not, will result in some "natural death" failures of the
components.

Since most products can be repaired (if they are worth it), each
repair extends the useful life of the product.  Think about your
automobile.  Extreme rusting of the chassis is about the only
failure that cannot be easily repaired.

George Alspaugh



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RE: Burn-in methods

[David Spencer]

Hi Massimo,
Doug and Tania have the right idea.  Basically, you want to find a
combination of operational and non-operational temperature excursions that
identify early life failures and manufacturing defects.  This is going to be
very specific to your product.  A successful burn-in programs has three key
areas:

1.  Degrees of separation.  You want to cycle the equipment over a range as
close to 100C as the parts you have permit.  Part of this may be done in a
non-operational state.
2.  Ramp rate.  I cannot speak to medical, but if your reliability is
expected to be anything like telecom, you want a minimum of 10C/minute.
3.  Repetition.  Depending on the time you have available, you should look
for at least 3 ramps with enough dwell (soak) at each extreme to allow your
product to reach that temperature.

I would like to reiterate Tania's suggestion to perform temperature cycling
on PCB's.  This is not only great for hi-pot testing, but is an excellent
way to find via defects if you have multi-layer boards.  Have your fab
perform temperature cycling prior to bare board continuity checking.

Good Luck!
Dave Spencer
Oresis Communications

-Original Message-
From: Doug McKean [mailto:dmck...@gte.net]
Sent: Monday, August 27, 2001 11:40 PM
To: emc-p...@majordomo.ieee.org
Subject: RE: Burn-in methods



Massimo Polignano wrote: 
>
> What kind of thermal cycling (temperature limits and test duration) to
> accelerate one year of life?

Accelerate one year of normal life to what - a month, a week? 

Very difficult to say.  And highly statistical to get 
sufficient confidence level. 

All based on the Arrhenius equation, look that up 
and then start looking into reliability engineering. 

The following is exceedingly rough but I've done it 
this way:  Basically, for every 10C increase in temp, 
your failure rates double.  For every 10C decrease, 
your failure rates halve. 

So, let's assume that at normal temp 20C, your 
product goes along at a normal pace and its 
normal life expectancy/MTBF is 6 years. 

Increase ambient by 10C to 30C, now you've halved the 
life expentancy of your product to 3 years.  Or, to 
put it another way, you've compressed each year of 
normal operation into 6 months.  Increase another 
10C to 40C ambient and you've compressed one year 
to 3 months.  50C and you've compressed one year 
to 6 weeks ... etc.  

BUT, you're upper limit may be only 40C! 

There's only so high you can go before you exceed 
the normal operating temps of the devices internal 
to your product.  And that's all determined by very 
careful measurements of the normal operating temps 
of the product. 

It is obviously much more complicated and involved 
than what I've presented here.  The semiconductor 
people have this down to an art. 

- Doug McKean 


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please no advertising Ed

[Stuart Lopata]

I don't think this is what they had in mind for this emc site!
I was actually hoping for some free tips.
"The cost of the Manufacturers Guide to Safety Agency Submittal is now 
available for the low price of 

$ 49.95  (US Dollars) 
  
(A small price to pay when compared to the cost of an agency or consultant!) "



Actually, I found many agencies willing to consult when you purchase their 
testing products.

Sorry Ed,

Stuart Lopata

RE: Burn-in methods

[Chris Maxwell]

Massimo,

Have you checked into the Reliability Analysis Center??

They are located at the former Griffiss Air Force Base in Rome, NY.
Electronics reliability is their sole purpose in life.  They may be able
to help you out (for a small fee :-)

You should be able to find them on the web by looking up "Reliability
Analysis Center".

If you have troubles contacting them; get in touch with me off-line.  I
can probably dig through my office and find a brochure with a phone/fax
number.

Best regards,

Chris Maxwell | Design Engineer - Optical Division
email chris.maxw...@nettest.com | dir +1 315 266 5128 | fax +1 315 797
8024

NetTest | 6 Rhoads Drive, Utica, NY 13502 | USA
web www.nettest.com | tel +1 315 797 4449 | 


 

> -Original Message-
> From: Doug McKean [SMTP:dmck...@gte.net]
> Sent: Tuesday, August 28, 2001 2:40 AM
> To:   emc-p...@majordomo.ieee.org
> Subject:  RE: Burn-in methods
> 
> 
> Massimo Polignano wrote: 
> >
> > What kind of thermal cycling (temperature limits and test duration)
> to
> > accelerate one year of life?
> 
> Accelerate one year of normal life to what - a month, a week? 
> 
> Very difficult to say.  And highly statistical to get 
> sufficient confidence level. 
> 
> All based on the Arrhenius equation, look that up 
> and then start looking into reliability engineering. 
> 
> The following is exceedingly rough but I've done it 
> this way:  Basically, for every 10C increase in temp, 
> your failure rates double.  For every 10C decrease, 
> your failure rates halve. 
> 
> So, let's assume that at normal temp 20C, your 
> product goes along at a normal pace and its 
> normal life expectancy/MTBF is 6 years. 
> 
> Increase ambient by 10C to 30C, now you've halved the 
> life expentancy of your product to 3 years.  Or, to 
> put it another way, you've compressed each year of 
> normal operation into 6 months.  Increase another 
> 10C to 40C ambient and you've compressed one year 
> to 3 months.  50C and you've compressed one year 
> to 6 weeks ... etc.  
> 
> BUT, you're upper limit may be only 40C! 
> 
> There's only so high you can go before you exceed 
> the normal operating temps of the devices internal 
> to your product.  And that's all determined by very 
> careful measurements of the normal operating temps 
> of the product. 
> 
> It is obviously much more complicated and involved 
> than what I've presented here.  The semiconductor 
> people have this down to an art. 
> 
> - Doug McKean 
> 
> 
> ---
> This message is from the IEEE EMC Society Product Safety
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Re: CE test suite for computers

[John Woodgate]

I read in !emc-pstc that George, David L  wrote
(in <3B10FF0A008FF6458711E6E375E830412C16A6@USTR-
EXCH2.na.uis.unisys.com>) about 'CE test suite for computers', on Mon,
27 Aug 2001:
>John:
>After all your years on the committee and having heard all the technical
>arguments, I am surprised the committee is still trying to justify the
>additional costs on each product?  If the power system is so bad it can be
>fixed cheaply for the consumer once and for 30+ years by changing the
>infrastructure.  No electronic product lasts 30 years and the cost is
>multiplied each time it is replaced.

Well, of course I am aware of your views and that particular economic
point. No doubt it will be taken into account by IEC SC77A/WG1/TF5a, on
which the ESI experts are in the minority. 
>  
>
>The bottom line is data now proves the European power system is very good

I am also aware of that data collection exercise, which indeed is strong
evidence. OTOH, I have the evidence of my own eyes and measurements
here. The mains waveform is very visibly 'flat-topped' and the THD
exceeds 4% on occasions (summer Sunday evenings, when almost all the
load is TV sets and home PCs; we still have very few home air-
conditioners). With regard to voltage changes and flicker, my own
experience is that DIY arc-welders can be a problem, but I don't see
much problem with anything else. This is largely reflected in the
relaxed limits in the still-unpublished (and largely unpublicised)
'other' Millennium Amendment - to IEC/EN61000-3-3.

>and these two standards are unnecessary but the standards makers (power
>utility people) 

As I wrote above, the ESI people are now in the minority of *attendees*
at the relevant meetings; they also point out that according to the
*membership lists* they have always been in the minority compared to
experts from equipment manufacturing, but not all members attended the
meetings before 1998, when IEC/TC74 realised what was happening, as I
realised in 1991.

>still insist in spite of proof, their systems are not so
>good.  In their view this is why we need limits on products and the power
>distribution system need not be fixed.

There is also a major problem at political level, insofar as all the ESI
companies in European countries where the system has been, or will be,
privatized, are subject to very strict (and somewhat uninformed)
financial control by government Regulators. The ESI is not being allowed
to finance its own harmonic mitigation, except in unusual circumstances.

Information has come to hand that these Regulators are not even in
favour of site-level harmonic mitigation, partly in case it allows some
'polluter' to avoid paying for the 'pollution', and regard equipment-
level control as the Only Solution. Compared with this mantra-oriented
attitude, the ESI people are pussy-cats (now!).
-- 
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk 
Eat mink and be dreary!

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Re: Burn-in methods

[Tania Grant]

Massimo,

I have no experience with medical devices, and there may be formal protocols 
that are recommended.   Here are a few that I've observed performed on ITE 
equipment for non-medical applications.
168 hours burn-in in a heat/humidity chamber, error free;-- if something fails, 
it is fixed or replaced, and the clock starts all over again (accelerated aging 
test).  However, after 25 years, I don't remember at which temperature; it 
obviously should be appropriate for the electronics used.
Subject unpopulated printed circuit cards in a heat/humidity chamber (don't 
remember how long) and then immediately after perform high potential tests to 
eliminate inner layer weaknesses.  This process really discovers weaknesses in 
the fabrication process of the printed circuits boards before any electronics 
are added.   
You also can buy "burned-in" components or those that are rated for higher 
temperatures, or have your component stock "burned-in" by an outside lab.   
The bigger question to ask is, just exactly what are you trying to find out, or 
what failure modes are you expecting, and gear your testing to that!  I am 
assuming you are after reliability, MTBF (how long?),  a safe failure mode.  
Are components or the solder process your main concern?  Perhaps you need to 
better monitor your solder process rather than cull by testing afterwards.  
There are many articles on quality processes that address this issue.
taniagr...@msn.com
- Original Message -
From: Massimo Polignano
Sent: Monday, August 27, 2001 10:05 AM
To: emc-p...@majordomo.ieee.org
Subject: Burn-in methods
  

I know it sounds as an out-of-topic for the emc-pstc mailing list. Anyway
somebody could have good links.

I am looking for some general advice for designing a burn-in process during
the in-line manufacturing of some electromedical devices. I would like to
answer basic questions like:
What kind of thermal cycling (temperature limits and test duration) to
accelerate one year of life?
What tests are the most suitable to find out manufacturing problems
(soldering mainly)?

Many thanks for any help.
Sincerely

m.p.
-
ESAOTE S.p.A. Massimo Polignano
Research & Product DevelopmentDesign Quality Control Mngr
Via di Caciolle,15tel:+39.055.4229402
I- 50127 Florence fax:+39.055.4223305
e-mail: massimo.polign...@esaote.com


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RE: Burn-in methods

[Doug McKean]

Massimo Polignano wrote: 
>
> What kind of thermal cycling (temperature limits and test duration) to
> accelerate one year of life?

Accelerate one year of normal life to what - a month, a week? 

Very difficult to say.  And highly statistical to get 
sufficient confidence level. 

All based on the Arrhenius equation, look that up 
and then start looking into reliability engineering. 

The following is exceedingly rough but I've done it 
this way:  Basically, for every 10C increase in temp, 
your failure rates double.  For every 10C decrease, 
your failure rates halve. 

So, let's assume that at normal temp 20C, your 
product goes along at a normal pace and its 
normal life expectancy/MTBF is 6 years. 

Increase ambient by 10C to 30C, now you've halved the 
life expentancy of your product to 3 years.  Or, to 
put it another way, you've compressed each year of 
normal operation into 6 months.  Increase another 
10C to 40C ambient and you've compressed one year 
to 3 months.  50C and you've compressed one year 
to 6 weeks ... etc.  

BUT, you're upper limit may be only 40C! 

There's only so high you can go before you exceed 
the normal operating temps of the devices internal 
to your product.  And that's all determined by very 
careful measurements of the normal operating temps 
of the product. 

It is obviously much more complicated and involved 
than what I've presented here.  The semiconductor 
people have this down to an art. 

- Doug McKean 


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