Ozone...

[Chris Dupres]

Good PSTC People.

Is Ozone a toxin?

Many years ago I had a factory inspector threaten to close down some High
Voltage test equipment because there was too much Ozone being produced. 
Lately we have had bad vibes about a Xerox copier making too much Ozone and
threats of ill health etc. to operators.

So my questions are: 
Are there any legal limits on the production of Ozone?  
Is it dangerous/what are the physiological effects?  
Where can I find out about it?  
Why do they sell Ozone generators for use in kitchens and bathrooms, does
it get rid of smells etc.?
Why do I get a headache and a tight chest when I'm around this stuff?

Funny stuff, Ozone.  Sure makes screws go rusty very quickly!

Any information anybody wants to share?

Chris Dupres
Surrey, UK.

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RE: EFT/B Generator for EN61000-4-4 Test

[Mike Hopkins]

I can recommend Transient Speialists, Tel: 708 246 3297; fax 708 482 3972 or
email lpit...@aol.com. They will do short term rentals plus provide some
support. 

Mike Hopkins
mhopk...@keytek.com

> -Original Message-
> From: Bailin Ma [SMTP:b...@namg.us.anritsu.com]
> Sent: Wednesday, October 07, 1998 2:28 PM
> To:   emc-p...@ieee.org
> Subject:  EFT/B Generator for EN61000-4-4 Test
> 
> Hi Group,
> 
> Do you know where I should go for renting a EFT/B Generator to run 
> EN61000-4-4 Test?
> 
> Thank you.
> Best Regards,
> Barry Ma
> 
> 
> 
> 
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RE: Grounding of screen room

[ed . price]

---

From: Bailin Ma 
Subject: RE: Grounding of screen room
List-Post: emc-pstc@listserv.ieee.org
Date: Wed, 7 Oct 98 9:18:11 PDT
To: emc-p...@ieee.org, emc-p...@ieee.org
Cc: Mekonen Buzuayene , Mekonen Buzuayene



Hi Ed,

Yes, I agree. The way you suggested is an ideal method to get 
Ambient noise 
in the Conducted emission test.   Please allow me to make two more 
points 
about impedance vs. frequency:

(1) It is inconvenient in practice to find "a resistive load sized 
to draw 
the same amount of power."  We have to make the equivalent load 
first, 
connect it to a power cord, and then plug the power cord into EUT 
port of 
the LISN. If we consider the equivalent load should be not only at 
60 Hz, 
also "equivalent" on 150 KHz - 30 MHz to the EUT, it would become 
much more 
troublesome. As a matter of fact, the frequency range of 150 KHz - 
30 MHz 
is of our interest.

(2) From the standpoint of spectrum analyzer, does it make lot of 
difference between using open circuit and equivalent load on EUT 
port of 
the LISN to detect the Ambient noise on 150 KHz - 30 MHz? 
 
Please correct me.
Best Regards,
Barry Ma
-

(Original text snipped as it was getting too ragged)

Barry:

You don't have to provide a dummy load which is the precise analog of the 
equipment to be tested. All you want to do is draw some fundamental power. 
Since I do Mil testing, I see power busses of 28VDC, 120/208 60Hz and 120/208 
400Hz.

To keep it simple, I constructed a load bank consisting of 16 surface mount 
light bulb sockets, all wired in parallel. I just screw in an array of 
25/60/75/100 Watt rated lamps until I get the necessary current. Sure, there's 
some unknown slight lead inductances and capacitances. But all I want to do is 
draw a few amps DC, and this setup works pretty well.

Ideally, it shouldn't make any difference between no-load and full-load 
conditions on the LISN. Your power source should be clean and quiet, your 
shielded enclosure powerline filters should be very effective, and your LISN 
also provides some filtering. But, in the real world, your power source may be 
very noisy, with additional RF environment currents induced onto the powerlines.

Some people may try to measure CE without a shielded enclosure; that should 
only be as a last resort. If you bought cheap powerline filters, or if you 
built them yourself, you can have two types of problems. First, your inductor 
design may not handle the DC current without going into magnetic saturation. 
The decreased incremental permeability will result in a dramatic drop in 
inductance, which will decrease the filter's filtering ability.

Second, the inductor may have been physically damaged during filter assembly. I 
have seen cracked toroids and poorly stacked laminated cores which have 
resulted in the filter creating harmonic energy content that wasn't in the 
original AC power.

I suppose that what I'm saying is that if you are creating a new measurement 
setup for each job you work on, I would measure the Ambient CE each time I do a 
CE test. I would be suspicious about the power source, filtering, etc. But, if 
you have a stable test setup, to which you bring product after product, I would 
suggest that you measure the ambient CE only periodically, maybe once a week, 
or at some other comfortable interval.

Of course, this advice doesn't pertain to those doing Mil-Std-461/462D testing, 
since that spec REQUIRES an Ambient at the time of each emission test.

Regards,

Ed


--
Ed Price
ed.pr...@cubic.com
Electromagnetic Compatibility Lab
Cubic Defense Systems
San Diego, CA.  USA
619-505-2780
List-Post: emc-pstc@listserv.ieee.org
Date: 10/07/98
Time: 12:18:32
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Re: CE Approval of equipment utilizing HPMs

[Peter Merguerian]

Michael Hello,

1. You state a "piece of equipment". Is this piece going to be 
integrated into an end-product? If so, it is wise to ask the Irish end-
product manufacturer or installer, what the requirements (EMC, 
Safety, etc.) for the end-product are and work accordingly. 
Otherwise, you may be designing to the wrong standards and/or 
Directives.

If your piece of equipment is a component, you might be exempt 
from the Machinery, LVD and EMC Directives depending on the 
equipment - not enough details were provided! However, you still 
need to design to the appropriate standards and Directives and 
prepare a file to submit to the end-product manufacturer or installer. 
The end-product manufacturer or installer having confidence in your 
test results, will then CE their equipment.

Regarding hazardous materials within a piece of equipment, you 
may wish to contact TUV Rheinland, Koln, Germany. If you wish, I 
can provide you with a contact name.

2. If you are the end-product manufacturer, you may not require to 
comply with the Machinery Directive - again depending on the type 
of equipment. A risk analysis should be made to determine if the 
risks are more mechanical or electrical. If mechanical hazards are 
more than the electrical hazards, the Machinery Directive route is 
more appropriate. If hazards are more electrical, the Low Voltage 
Directive route is more appropriate. 

3. Please be aware that for the Machinery Directive, the Official 
Journal lists many standards. You must make sure that you pick 
the most appropriate standards (and believe me for a typical 
Machinery Directive investigation you could easily use up to 5 or 6 
standards). Many people think that by complying with EN60204 
they solved their Machinery Directive requirements. This is 
absolutely incorrect since this standard pertains to the electrical 
requirements for machinery. There are many other standards to 
consider. 

4. Please be aware that other Directives might be needed - again 
depends what your piece of equipment does. For example, if 
conneccted to the telecom network, you may need to comply with 
the TTE Directive (unless your modem or other telecom interface 
has a host-independent European Approval).

Should you wish, I can discuss these requirements in detail with 
you and our PSTC members; however, I believe that you need to 
provide me with additional info regarding your equipment before I 
proceed any further.



From:   "Michael Garretson" 
To: 
Subject:CE Approval of equipment utilizing HPMs
Date sent:  Mon, 5 Oct 1998 17:17:45 -0700
Send reply to:  "Michael Garretson" 

> I am forwarding this question on behalf of one of our clients.  Please
> forgive the lack of detail in some areas.  CE marking is not within the
> normal scope of my responsibilities, so my awareness of the specific
> requirements is not great.  I would appreciate clarification of some of
> these issues so that we can provide the information to my client in the
> early stages of their design evaluation.  It is my understanding that they
> are working with a US-based lab for portions of this work, but are not
> confident that they are being provided with accurate information regarding
> what requirements may exist to achieve CE marking of the equipment.
> 
> My company is working with a manufacturer that is intending to send a piece
> of equipment to Ireland for the first time.  The equipment is intended to be
> installed in a non-classified location, however it uses flammable liquid
> (hazardous) process chemicals (details unavailable at this time).  I am
> under the impression that the manufacturer plans to assemble a Technical
> Construction File in order to demonstrate conformance with the applicable
> requirements of the pertinent CE directives.
> 
> At this time, they intend to demonstrate compliance with the applicable
> portions of the Low Voltage, Machinery and EMC directives.  Due to the
> hazardous chemical issues, it has also been suggested that conformance with
> 94/009 EEC may be required.
> 
> I would appreciate it if anyone can provide me with guidance on whether this
> approach is reasonable or whether alternatives need to be pursued.  Also if
> there are specific pitfalls that this manufacturer may encounter, please
> indicate where those may be, as well.
> 
> If you require additional detail in order to assist my client with this
> matter, please let me know what information you require and I will pass the
> request on to my client.
> 
> Michael Garretson
> Sr. Compliance Engineer
> Electro-Test, Inc.
> +1 503 653 6781  voice
> +1 503 659 9733  fax
> mailto:m.garret...@ieee.org
> 
> 
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> j...@gwmail.monarch.

Power Switcher IC

[Darrell Locke (MSMail)]

We have a new display panel design that requires a a small switcher for
power.   The end product must meet Class B emissions.  We are planning
on using the Linear Technology LT1376 IC which contains the control
circuitry and switch.  It operates at 500KHz and is rated at 1.25 amps.
Has anyone had any specific problems or horror stories using this part
with respect to emissions.

Thanks very much

Darrell Locke
Advanced Input Devices

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Re: Room grounding

[Lfresearch]

Mike,

sorry you disagree.

Inside the room, all equipment is referenced to the room itself, there is no
new safety risk introduced by the room being grounded differently.

Outside the room, again, all equipment is referenced tightly to the room, so
the operator does not see any differential.

Should lightning strike the building, then true, the building earth potential
may lift, but the operator is protected because he is referenced to the room
which will not move much because the energy has been dissipated by the
building earthing system.

I state again this is for performance reasons, and is accepted practice. In a
true Faraday shielded room, earthing the room is not even neccessary. Mind
you, since these don't exist off the shelf, I'll stick to grounding using my
original guidlines. NEC inspectors, when the rationale is explained to them
have little problem. However, I have come across situations were the two
unique earths were tied by a very heavy inductor

Best regards,

Derek N. Walton

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EFT/B Generator for EN61000-4-4 Test

[Bailin Ma]

Hi Group,

Do you know where I should go for renting a EFT/B Generator to run 
EN61000-4-4 Test?

Thank you.
Best Regards,
Barry Ma




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RE: Grounding of screen room

[Bailin Ma]

Hi Ed,

Yes, I agree. The way you suggested is an ideal method to get Ambient noise 
in the Conducted emission test.   Please allow me to make two more points 
about impedance vs. frequency:

(1) It is inconvenient in practice to find "a resistive load sized to draw 
the same amount of power."  We have to make the equivalent load first, 
connect it to a power cord, and then plug the power cord into EUT port of 
the LISN. If we consider the equivalent load should be not only at 60 Hz, 
also "equivalent" on 150 KHz - 30 MHz to the EUT, it would become much more 
troublesome. As a matter of fact, the frequency range of 150 KHz - 30 MHz 
is of our interest.

(2) From the standpoint of spectrum analyzer, does it make lot of 
difference between using open circuit and equivalent load on EUT port of 
the LISN to detect the Ambient noise on 150 KHz - 30 MHz? 
 
Please correct me.
Best Regards,
Barry Ma
-
Original Text
From: , on 10/7/98 9:34 AM:


  From: Bailin Ma 
  Subject: RE: Grounding of screen room
  Date: Tue, 6 Oct 98 14:35:43 PDT 
  To: emc-p...@ieee.org, TREG 
  Cc: Mekonen Buzuayene 


> Hi Lauren,
> 
> It is my understanding that properly grounding the screen room is 
important 
> in Conducted emission test and have little effect on Radiated emission 
> test. The way you described is a very good and simple method for 
evaluating 
> the shielding effectiveness (SE) of  the screen room. The SE, however, is 
> not critical in Conducted emission test.
> 
> A simple way, similar to what you described, to evaluate the background 
> noise of Conducted emission test is turning off the power of DUT when you 
> get ready to run the test  to see if you can 'hear' anything on the 
> spectrum analyzer.
> 
> Please correct me.

Pardon, Barry, but I think I will. You should measure the Ambient conducted 
emission level by loading the LISN's with a resistive load sized to draw 
the same amount of power as your typical test specimen. This loads the 
external power source (some sites may be using their own generator or 
electronic power converter), allows the shielded enclosure powerline filter 
to work into a load impedance more normal than an open circuit, and 
validates the performance of the powerline filter and the LISN's (cheap or 
damaged filter inductors will degrade or even create noise).


Regards,

Ed

--
Ed Price
ed.pr...@cubic.com
Electromagnetic Compatibility Lab
Cubic Defense Systems
San Diego, CA.  USA
619-505-2780
List-Post: emc-pstc@listserv.ieee.org
Date: 10/07/1998
Time: 08:34:44
--


o


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RE: South & North Korea & Russia

[Schanker, Jack]

Sarmad:

For good details on Russian safety (and EMC) approvals, check out the
RFI Labs page on the subject at:
http://www.rfi.co.uk/Technical/TechPaper_Product_Cert_Russia.htm

Jack

Jacob Z. Schanker, P.E.
Director of Agency Compliance
Microwave Data Systems
175 Science Parkway
Rochester, NY 14620 USA
+716 242 8454 (voice)
+716 241 5590 (fax)
jschan...@mdsroc.com
--

> --
> From: salba...@hns.com[SMTP:salba...@hns.com]
> Sent: Tuesday, October 06, 1998 10:34 AM
> To:   emc-p...@ieee.org
> Subject:  South & North Korea & Russia
> 
> 
> 
> Hello Everyone,
> 
> Does anyone have an idea on what will be the equivalent for the UL
> 1950  in
> North, South Korea and in Russia?  Do they have a country specific
> Standard?  or they follow the EN60950 ?
> 
> Your help is highly appreciated.
> 
> 
> 
> Sarmad Albanna
> Compliance Engineer
> Hughes Network Systems
> PH (301) 428-5705
> Fax (301) 428-2835
> 
> 
> 
> -
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> 

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Re: Korea EMC & Saffety Certtification of ITE

[Ryan Kim]

 I just have the following information for you.
 I also do not have phone numbers.

1. IBM Austin EMC, Texas
2. IBM Endicott EMC, Newyork
3. IBM Research Triangle Park EMC, NC
4. IBM MID-HUDSON EMC, MHV

The above information is from list of Korea government authorized lab.
It has only Korea IBM phone numbers on it.

Regards,

Ryan Kim

-Original Message-
From: Grant, Tania (Tania) 
To: 'Ryan Kim' 
List-Post: emc-pstc@listserv.ieee.org
Date: Tuesday, October 06, 1998 4:01 PM
Subject: RE: Korea EMC & Saffety Certtification of ITE


>Thank you, Ryan, for this very interesting news.  Could you provide us
>with addresses and phone number of these IBM labs that were accredited
>by Korea?
>
> Tania Grant, Lucent Technologies, Octel Messaging Division
> tgr...@lucent.com TEL:  +408 324 5238;  FAX:  +408
>324 3813
>
>
> --
> From:  Ryan Kim[SMTP:hait...@soback.kornet21.net]
> Sent:  Tuesday, October 06, 1998 8:21 AM
> To:  CTL
> Cc:  emc-pstc
> Subject:  Re: Korea EMC & Saffety Certtification of ITE
>
> 쟅BM has 4 Korea government approved labs which were accredited
>approxi.
> 7 years ago.?There is no other lab in U.S.A. since then.
> ?
> US might go MRA with Korea next year July.?I am not sure exact
>date.
> ?
> Only printer, monitor and AC/CD adaptor are required for Safety
>Certi. among
> ITE products.
> ?
> Regards,
> ?
> Ryan Kim
> ?
>
> -Original Message-
> From: CTL < c...@prodigy.net>
> To: hait...@soback.kornet21.net <
>hait...@soback.kornet21.net>
> Date: Tuesday, October 06, 1998 8:11 AM
> Subject: Korea EMC & Saffety Certtification of ITE
>
>
> Is there a lab located in the US that is approved by
>Korea for EMC Testing?
> Does the US have an MRA with Korea?
> Is Safety Certification Required for ITE (computers)?
> ?
> Thanks & Best Regards,
> ?
> Pryor McGinnis
> Compliance Test Laboratories
> PO Box 120, 137 Airport Road
> Liberty, SC 29657
> e-mail: c...@prodity.net
> Phone: 864 843 1604
> FAX:젨젨 864 843 1812
>
>


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RE: Grounding of screen room

[ed . price]

  From: Bailin Ma 
  Subject: RE: Grounding of screen room
  Date: Tue, 6 Oct 98 14:35:43 PDT 
  To: emc-p...@ieee.org, TREG 
  Cc: Mekonen Buzuayene 


> Hi Lauren,
> 
> It is my understanding that properly grounding the screen room is important 
> in Conducted emission test and have little effect on Radiated emission 
> test. The way you described is a very good and simple method for evaluating 
> the shielding effectiveness (SE) of  the screen room. The SE, however, is 
> not critical in Conducted emission test.
> 
> A simple way, similar to what you described, to evaluate the background 
> noise of Conducted emission test is turning off the power of DUT when you 
> get ready to run the test  to see if you can 'hear' anything on the 
> spectrum analyzer.
> 
> Please correct me.

Pardon, Barry, but I think I will. You should measure the Ambient conducted 
emission level by loading the LISN's with a resistive load sized to draw the 
same amount of power as your typical test specimen. This loads the external 
power source (some sites may be using their own generator or electronic power 
converter), allows the shielded enclosure powerline filter to work into a load 
impedance more normal than an open circuit, and validates the performance of 
the powerline filter and the LISN's (cheap or damaged filter inductors will 
degrade or even create noise).


Regards,

Ed

--
Ed Price
ed.pr...@cubic.com
Electromagnetic Compatibility Lab
Cubic Defense Systems
San Diego, CA.  USA
619-505-2780
List-Post: emc-pstc@listserv.ieee.org
Date: 10/07/1998
Time: 08:34:44
--



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RE: Lab qualification - and a note on reports

[Gary McInturff]

Kate, 
My apologies for the apparent slight. In the US, where I'm located,
NVLAP and A2LA were simply familiar to me. I happen to us NVLAP when I
qualified a former employers site. Quite possibly their are more
certifying bodies in the US than just those two and if they carry NIST
credentials I would accept them as providers of this service as well.
At the core of the MRA's coming into effect is that the
countries involved have labs that meet some sort of national independent
inspection, and I believe
that the same IS0 Guide 25 is at the heart. So depending on the country
in which you work the inspection agency name will change but the
recommendations are the same.
I would also agree that an example of the report and the time to
produce, and obviously report and test fees should be a checklist item.
I would be interested in seeing a copy
Gary
-Original Message-
From:   Kate MacLean [SMTP:k.macl...@aprel.com]
Sent:   Tuesday, October 06, 1998 8:52 PM
To: gmcintu...@packetengines.com; Randall Flinders;
'emc-pstc'
Subject:RE: Lab qualification - and a note on reports

From:   Gary McInturff

To: "Robert F. Martin ITS/QS-Box"
,
Randall Flinders
,
"'emc-pstc'" 
Subject:RE: Lab qualification
Date sent:  Tue, 6 Oct 1998 16:09:41 -0700 
Send reply to:  Gary McInturff


> Yeah, I second that. I try to believe in as little
confirmation as
> possible. Extended stacks of paper don't verify anything. For
the EMC
> stuff I think that you really want to deal with labs that have
NIST
> approval through NVLAP or A2LA. Among other things if you
don't need an
> FCC ID you can ship your product as soon as you have the
report rather
> than wait for the 6 weeks of FCC time. These labs are also the
only ones
> that are going to be covered in the MRA's with Europe etc



Just a reminder, All - 

Canadian labs which are accredited by the Standards Council of 
Canada also enjoy the same status as A2LA and NVLAP labs with 
respect to FCC DoC rules.  The accreditation standard is also
ISO 
Guide 25. The Canadian - EU MRA is signed and in the 
implementation phase, by the way...

I would add one additional suggestion to all of this discussion
of lab 
qualification:

Many labs, although they may be technically competent, and have 
the quality systems and controls to carry out accurate work,
fail to 
properly showcase their work in the reports which they produce
for 
their clients.  Agency personnel (FCC, IC, etc) HAVE 
COMMENTED TO ME ON THIS - understand that a poorly 
prepared report reflects poorly on you as a manufacturer.  

This is a mystery to us, as we see our reports as being the 
tangible output of our work - test, certifcation or research.
Ask to 
be shown a sample report!  And beware of offers of "free" or 
"cheap" reports - you will often get what you pay for.  It takes

proper time and attention to carry out analysis of data and to 
prepare reports and submissions.

Regards,
Kathy 




Kathy MacLean
President 
APREL Laboratories
-Research-Consulting-Training-Certification Testing-
-Specialists in Electromagnetics, Acoustics, 
Wireless Telecommunications, and SAR-
51 Spectrum Way, Nepean, Ontario, Canada K2R 1E6
(613) 820-2730  (613) 820-4161(fax) 
http://www.aprel.com

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RE: Lab qualification

[Matejic, Mirko]

ISO/DIS 17025 is DRAFT industry standard which has been produced as the
result of extensive experience of the implementation of ISO/IEC Guide
25: 1990 and EN 4500l :1989 both of which it will replace. It contains
all of the requirements that testing and calibration laboratories have
to meet if they wish to demonstrate that they operate a quality system,
are technically competent, and are able to generate technically valid
results. It is likely that it would be adopted with some modifications.
Voting on this document terminates on 1998-12-09. If you have
suggestions or comments on this document, please let me know. File will
be posted soon on http://www.rcic.com   IEC
standards. 

My suggestions are along the line of already posted responses. Consider
only test laboratories accredited by NVLAP, A2LA or any other accreditor
having MRA with either of them. Let them assess test laboratories for
you. Personal visit to the laboratory could be valuable.

Regards,

Mirko Matejic



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RE: Room grounding

[Mike Hopkins]

I absolutely disagree about having a separate ground for the shielded room.
Any ac fault inside the room can potentially cause a personnel hazard, as
will any lightning strike to the vicinity. A separate ground for the
shielded room is acceptable ONLY if it is bonded to building ground. The
risk may be minimal, but why take any at all.

Mike Hopkins
mhopk...@keytek.com

> -Original Message-
> From: lfresea...@aol.com [SMTP:lfresea...@aol.com]
> Sent: Tuesday, October 06, 1998 3:36 PM
> To:   emc-p...@majordomo.ieee.org
> Subject:  Room grounding
> 
> Chaps,
> 
> The grounding of a shield room has always been a tricky subject. In the US
> we
> have the NEC code that basically want's everything connected, which
> contradicts some EMC requirements. The Shield room hence needs some
> tricks:
> 
> 1) One of the functions of the outer skin is to terminate impinging
> fields.
> Current is generated on the shield surface that will flow across joints
> and
> seams ( and hence leak into the chamber ) unless it's routed somewhere
> Earth.
> 
> 2) While buildings usually have a good earth, they typically have a noisy
> earth. The last thing we need is building noise on our room, so an earth
> dedicated to the chamber is provided.
> 
> 3) To stop building noise from using the shield room earth, all metallic
> connections are cut, and plastic used instead. This is where the NEC folks
> can
> get upset. Their concern is that the two grounds could lift with respect
> to
> each other I've never seen that happen, and I've gone looking for it.
> So
> that I can sleep at night, I ensure that an operator can't touch metal
> referenced to the different grounds at any one time.
> 
> 4) Power supplied to the room has to be directly connected. To stop
> building
> noise from entering the room through this wiring, the noise is removed to
> the
> case of a filter. I've located my filters very close to the room single
> point
> room earth connection, so the noise can get there easily without crossing
> one
> of my room seams or joints.
> 
> 5) Any equipment I use with the room is referenced to the room ground.
> Power
> for this equipment is filtered at the same point the room power is. Most
> instrumentation used in EMC is quiet so they don't supply much noise.
> 
> I don't believe there is guess work involved with room grounding. The
> above is
> based on conversations with many room installers. I suggest that if you
> have
> specific questions, contact the folks that made yours.
> 
> -
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RE: Grounding of screen room

[Ing. Gert Gremmen]

For a screened room to function as a screened room, no earth is required.
It's the metal conduit of the shielding material that will be reference
potential
(if you insist : ground) for all measurements. All external cables (mains)
should
be filtered to this reference potential, preferably to the outside surface
of the
room wall.
>From point of electrical safety some GROUNDING with wire can be
justified, but this will not influence performance in any way.

If it does, something in your measurement setup is very wrong.


Regards

Gert Gremmen


== Ce-test, Qualified testing ==
Consultants in EMC, Electrical safety and Telecommunication
Compliance tests for European standards and ce-marking
Member of NEC / IEC  committee for EMC.
Our Web presence: http://www.cetest.nl
List of current harmonized standards http://www.cetest.nl/emc-harm.htm
15 great tips for the EMC-designer http://www.cetest.nl/features01.htm




-Original Message-
From:   owner-emc-p...@majordomo.ieee.org
[mailto:owner-emc-p...@majordomo.ieee.org] On Behalf Of peterh...@aol.com
Sent:   dinsdag 6 oktober 1998 7:57
To: emc-p...@majordomo.ieee.org
Subject:Grounding of screen room

Hello group,

Can someone tell me what is the best method to find out and ensure that a
screen room is adequately grounded? I have access to an screen room for
conducted emissions, but I am not sure about its grounding. Any hint is
appreciated.

Thanks
Peter Hays

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RE: Lab qualification - and a note on reports

[Kate MacLean]

From:   Gary McInturff 
To: "Robert F. Martin ITS/QS-Box" ,
Randall Flinders
,
"'emc-pstc'" 
Subject:RE: Lab qualification
Date sent:  Tue, 6 Oct 1998 16:09:41 -0700 
Send reply to:  Gary McInturff 

> Yeah, I second that. I try to believe in as little confirmation as
> possible. Extended stacks of paper don't verify anything. For the EMC
> stuff I think that you really want to deal with labs that have NIST
> approval through NVLAP or A2LA. Among other things if you don't need an
> FCC ID you can ship your product as soon as you have the report rather
> than wait for the 6 weeks of FCC time. These labs are also the only ones
> that are going to be covered in the MRA's with Europe etc



Just a reminder, All - 

Canadian labs which are accredited by the Standards Council of 
Canada also enjoy the same status as A2LA and NVLAP labs with 
respect to FCC DoC rules.  The accreditation standard is also ISO 
Guide 25. The Canadian - EU MRA is signed and in the 
implementation phase, by the way...

I would add one additional suggestion to all of this discussion of lab 
qualification:

Many labs, although they may be technically competent, and have 
the quality systems and controls to carry out accurate work, fail to 
properly showcase their work in the reports which they produce for 
their clients.  Agency personnel (FCC, IC, etc) HAVE 
COMMENTED TO ME ON THIS - understand that a poorly 
prepared report reflects poorly on you as a manufacturer.  

This is a mystery to us, as we see our reports as being the 
tangible output of our work - test, certifcation or research.  Ask to 
be shown a sample report!  And beware of offers of "free" or 
"cheap" reports - you will often get what you pay for.  It takes 
proper time and attention to carry out analysis of data and to 
prepare reports and submissions.

Regards,
Kathy 




Kathy MacLean
President 
APREL Laboratories
-Research-Consulting-Training-Certification Testing-
-Specialists in Electromagnetics, Acoustics, 
Wireless Telecommunications, and SAR-
51 Spectrum Way, Nepean, Ontario, Canada K2R 1E6
(613) 820-2730  (613) 820-4161(fax) 
http://www.aprel.com

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CENELEC Decisions on EN 60950

[Egon H. Varju]

Greetings,

For those of you that may be interested in EN 60950 and all other clones of
IEC 950, I have scanned and OCR'd the latest List of Decisions, as of July
1998.

Since not everyone is interested in this, I will not attach it to this
message.  If you want a copy, you can get it from my website:

http://www.varju.bc.ca/standards/cenlec98.txt

Last year's List of Decisions is also there:

http://www.varju.bc.ca/standards/cenlec97.txt

Caution:  For some reason, this address is case-sensitive, so you have to
enter it in your web browser exactly as shown.  Easiest way is to just
click on it above.  If you're really hopelessly computer-challenged, send
me an e-mail, and I'll send you a copy.

Hope you find this to be useful information.

Egon :-)


__

 Egon H. Varju, P.Eng.
 CSA Pacific Region
 Tel:   1-604-244-6640   HAVE MODEM  -  WILL TRAVEL
 Fax:   1-604-244-6600
 E-mail:eva...@csi.com
var...@csa.ca
e...@varju.bc.ca
__




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RE: Lab qualification

[Gary McInturff]

Yeah, I second that. I try to believe in as little confirmation as
possible. Extended stacks of paper don't verify anything. For the EMC
stuff I think that you really want to deal with labs that have NIST
approval through NVLAP or A2LA. Among other things if you don't need an
FCC ID you can ship your product as soon as you have the report rather
than wait for the 6 weeks of FCC time. These labs are also the only ones
that are going to be covered in the MRA's with Europe etc
In order to complete this task they are suppose to have a
quality system in place (pretty much defined by ISO guide 25) that does
most of the work for  you. The contents of that guide pretty much
describe processes which will insure proper test equipment, test
procedures, tracking, calibration et al. I would also ask for copies of
the bi-annual audits or corrective action items generated from the
audits. Hopefully, the corrective action items is small or non-existent.
So if they have a valid certificate I can be assured that they
have all the other reams of paper on file, that it addresses most of the
quality issues I would have, and that the lab is audited both internally
and externally. Therefore I don't need to find a corner of my office to
put all of this data - which will never get looked at anyway! I prefer
to let the auditing agency do all of this work and paper retention for
me.
Not all testing is currently certified by NIST et cetera.  I
don't believe that you can be certified by anybody for ESD yet. But if
the lab is certified to do the EMI it would be very reasonable to assume
that the procedures that qualified them for EMI would be followed during
any other testing they claim to be qualified to perform.
If you wish to use labs that have no outside certification I
would develop a checklist of things  you want to have controlled and I
would probably take them right out of the ISO guide 25 document - it is
intended afterall to be a quality guide for test laboratories.
Regardless of the method you use I would strongly recommend that
you actually visit each of the labs and talk with the people doing the
work. Paper is one thing the people that do the tests certainly are
another. I once had an emissions that was periodic extended above the
noise floor significantly, it was compliant but hard to miss. The
certified lab technician was going to ignore the signal (it should have
been part of the suspects at a very minimum) and when I asked him about
it he said it was an ambient. He based that on the cyclic nature rather
than any list of known ambients or any other tests. I quickly dropped
them from my vendor list.
Gary McInturff


-Original Message-
From:   Robert F. Martin ITS/QS-Box [SMTP:r...@itsqs.com]
Sent:   Tuesday, October 06, 1998 11:41 AM
To: Randall Flinders; 'emc-pstc'
Subject:RE: Lab qualification

I am not sure what level of detail that you are looking
for, but you might try to look at EN45001/2, and the associated guide
for EMC labs that was published in the UK. Another avenue would be to
model your format after the NVLAP program. They have a Handbook 150
(general) and 150-x (for specific methods (FCC, MIL)) for laboratories
applying for accreditation, which may be useful. 

Bob Martin
Sr. Technical Manager
Intertek Testing Services
(978)263-2662
fax(978)263-7086
r...@itsqs.com

The opinions expressed are my own and not necessarily
those of my employer.


-Original Message-
From:   Randall Flinders
[SMTP:randall.flind...@emulex.com]
Sent:   Monday, October 05, 1998 11:34 AM
To: 'emc-pstc'
Subject:Lab qualification

Hello group.

I am facing the task of writing a corporate
procedure for qualifying EMC Test Labs as vendors.  The procedure will
approve each vendor on a test by test basis, and a spec by spec basis.
(For example - one lab may be approved for radiated emissions, but not
for EFT testing, while another lab may be approved for testing to FCC
Part 15, but not to AS/NZS 3548.)

Could anyone suggest any documents which I can
use I the preparation of this procedure?  If anyone has faced this task
in the past, pointers would be appreciated as well.  So far, the only
document I have found to use as a guide is ISO Guide 25-B.  Any other
suggestions would be appreciated.

Regards,


Randy Flinders
EMC Engineer
Emulex Network Systems
(714) 513-8012
randall.flind...@emulex.com
 

S&N Korea and Russia Requirements

[salbanna]

Thanks all for your fast helpful responses.



Sarmad Albanna
Compliance Engineer
Hughes Network Systems
Ph (301) 428-5705
Fax (301) 428-2835




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