Re: [PSES] Reading or Limit Conversion?

[itl-emc user group]

Thanks to all who managed to respond.

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web www.itlglobal.org

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From: itl-emc user group 
Sent: Monday, October 28, 2019 8:37 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the frequency range of 
30-1000 MHz for test distance greater than 3 or 10 meters.
Testing is normally performed at either 3 meters or 10 meters on an Open Area 
Test Site.
A question has arisen concerning reporting the test results in these cases.
Any opinions concerning which should be converted:

  1.  Convert the limit to the relevant test distance (3 meters or 10 meters) 
by adding correction factor or
  2.  Convert the reading to the unit and test distance listed in the standard 
(convert dBµV to µV and add correction factor for distance)
On some occasions I have seen option b. above used.
Which option is preferable?
All opinions welcome

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web www.itlglobal.org

[cid:image003.png@01D58E2A.52E2E5F0]ITL Waze: https://waze.com/ul/hsv8vccn2j

Fill out Customer Satisfaction 
Survey
Global Certifications You Can Trust
This e-mail message may contain privileged or confidential information.
If you are not the intended recipient, you may not disclose, use, disseminate, 
distribute, copy or rely upon this message or attachment in any way. If you 
received this e-mail message in error, please return by forwarding the message 
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Attachments are not permitted but the IEEE PSES Online Communities site at 
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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 to 


All emc-pstc postings are archived and searchable on the web at:
http://www.ieee-pses.org/emc-pstc.html

Attachments are not permitted but the IEEE PSES Online Communities site at 
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used 
formats), large files, etc.

Website:  http://www.ieee-pses.org/
Instructions:  http://www.ieee-pses.org/list.html (including how to unsubscribe)
List rules: http://www.ieee-pses.org/listrules.html

For help, send mail to the list administrators:
Scott Douglas 
Mike Cantwell 

For policy questions, send mail to:
Jim Bacher:  
David Heald: 

Re: [PSES] Reading or Limit Conversion?

[Ken Javor]

Completely off-topic, but...

The input impedance of a tuned dipole is 72 ‡. That looks more magnetic than
electric compared to 377 ‡. Also, if you are in close to the tuned dipole,
then you would see magnetic at the center (current maximum) and very high
electric at the tips (no current at all).

Now if we are talking an electrically short dipole, then yes, it¹s pretty
much all electric.

Ken Javor
Phone: (256) 650-5261



From: John Woodgate 
Organization: J M Woodgate and Associates
Reply-To: John Woodgate 
Date: Mon, 28 Oct 2019 22:24:51 +
To: 
Subject: Re: [PSES] Reading or Limit Conversion?

   

That's because of near-field effects. You can often get any result you like
(or don't like) when measuring in the near field. And there is no
relationship between the electric and magnetic field strengths. Consider a
dipole - much electric but hardly any magnetic. Then consider a solenoid -
just the opposite.
 
 

In a truly unperturbed far field, the levels are predictable. The problem of
interpolation, extrapolation or some other way of processing the measured
results is that, because standards are inconsistent, whichever way you do
the processing, it can be challenged. If all the standards were consistent,
there would be one standardized process and no possibility of a challenge.
 
 
Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk 
Rayleigh, Essex UK
 
On 2019-10-28 20:47, Grasso, Charles wrote:
 
 
>  
>  
> 
> Take the reading. It¹s the only way to be sure..
>  
>  
>  
> It is not unusual for a product to pass @ 3m and then fail at 10m (or vice
> versa).
>  
>  
>  
>  
> 
> Thanks!
>  
>  
>  
> Charles Grasso 
>  
> W: 303-706-5467
>  
>  
>  
>  
>  
>  
> 
> From: John Woodgate [mailto:j...@woodjohn.uk]
>  Sent: Monday, October 28, 2019 1:30 AM
>  To: EMC-PSTC@LISTSERV.IEEE.ORG
>  Subject: Re: [PSES] Reading or Limit Conversion?
>  
>  
>  
>  
>  
>  This message originated outside of DISH and was sent by:
> owner-emc-p...@listserv.ieee.org
>  
> 
> This inconsistency (in the underlying CISPR standards) should be addressed by
> CISPR, but it is difficult to get consensus whenever it is discussed.
>  
> Best wishes
>  
> John Woodgate OOO-Own Opinions Only
>  
> J M Woodgate and Associates www.woodjohn.uk 
>  
> Rayleigh, Essex UK
>  
>  
> 
> On 2019-10-28 07:05, Charlie Blackham wrote:
>  
>  
>>  
>> David
>>  
>>  
>>  
>> Hmm, different standards appear to deal with this differently:
>>  
>> * EN 55011:2009 section 6.2.2.3 instructs you to normalise the measured data
>> to the specified distance in the standard
>> * EN 55032:2015 section 9 instructs you to adjust the limits (in fact it
>> gives limits for 3 and 10m which are 10 dB apart and not 10.45dB apart if you
>> extrapolate using 20LogD)
>> * ANSI 63-4:2014 instructs you to extrapolate the results
>>  
>>  
>>  
>> If the standard or test method doesn¹t specify, I guess the important thing
>> is to be clear in the report as to what¹s been done.
>>  
>>  
>>  
>> Regards
>>  
>> Charlie
>>  
>>  
>>  
>>  
>> 
>> Charlie Blackham
>>  
>> Sulis Consultants Ltd
>>  
>> Tel: +44 (0)7946 624317
>>  
>> Web: https://sulisconsultants.com/ 
>>  
>> Registered in England and Wales, number 05466247
>>  
>>  
>>  
>>  
>>  
>>  
>> 
>> From: itl-emc user group   
>>  Sent: 28 October 2019 06:37
>>  To: EMC-PSTC@LISTSERV.IEEE.ORG
>>  Subject: [PSES] Reading or Limit Conversion?
>>  
>>  
>>  
>>  
>>  
>> A number of standards list radiated emission limits in the frequency range of
>> 30-1000 MHz for test distance greater than 3 or 10 meters.
>>  
>> Testing is normally performed at either 3 meters or 10 meters on an Open Area
>> Test Site.
>>  
>> A question has arisen concerning reporting the test results in these cases.
>>  
>> Any opinions concerning which should be converted:
>>  
>>  a.   Convert the limit to the relevant test distance (3 meters or 10
>> meters) by adding correction factor or
>>  
>>  b.  Convert the reading to the unit and test distance listed in the
>> standard (convert dBµV to µV and add correction factor for distance)
>>  
>> On some occasions I have seen option b. above used.
>>  
>> Which option is preferable?
>>  
>> All opinions welcome
>>  
>>  
>>  
>> Regards,
>>  
>> David Shidlowsky | Technical Reviewer
>>  
>> Address 1 Bat-Sheva St. LOD 7120101 Israel
>>  
>> Tel 972-8-9186113 Fax 972-8-9153101
>>  
>> Mail : dav...@itlglobal.org  /dav...@itl.co.il
>>  /e...@itl.co.il  Web www.itlglobal.org
>> 
>>  
>>  
>>  
>> ITL Waze: https://waze.com/ul/hsv8vccn2j 
>>  
>>  
>>  
>> Fill out Customer Satisfaction Survey
>> 
>>  
>> Global Certifications You Can Trust
>>  
>> This e-mail message may 

Re: [PSES] Reading or Limit Conversion?

[John Woodgate]

That's because of near-field effects. You can often get any result you 
like (or don't like) when measuring in the near field. And there is no 
relationship between the electric and magnetic field strengths. Consider 
a dipole - much electric but hardly any magnetic. Then consider a 
solenoid - just the opposite.


In a truly unperturbed far field, the levels are predictable. The 
problem of interpolation, extrapolation or some other way of processing 
the measured results is that, because standards are inconsistent, 
whichever way you do the processing, it can be challenged. If all the 
standards were consistent, there would be one standardized process and 
no possibility of a challenge.


Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk
Rayleigh, Essex UK

On 2019-10-28 20:47, Grasso, Charles wrote:


Take the reading. It’s the only way to be sure..

It is not unusual for a product to pass @ 3m and then fail at 10m (or 
vice versa).


Thanks!

Charles Grasso

W: 303-706-5467

*From:* John Woodgate [mailto:j...@woodjohn.uk]
*Sent:* Monday, October 28, 2019 1:30 AM
*To:* EMC-PSTC@LISTSERV.IEEE.ORG
*Subject:* Re: [PSES] Reading or Limit Conversion?

 This message originated outside of DISH and was sent by: 
owner-emc-p...@listserv.ieee.org 



This inconsistency (in the underlying CISPR standards) should be 
addressed by CISPR, but it is difficult to get consensus whenever it 
is discussed.


Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associateswww.woodjohn.uk  
Rayleigh, Essex UK

On 2019-10-28 07:05, Charlie Blackham wrote:

David

Hmm, different standards appear to deal with this differently:

  * EN 55011:2009 section 6.2.2.3 instructs you to normalise the
measured data to the specified distance in the standard
  * EN 55032:2015 section 9 instructs you to adjust the limits (in
fact it gives limits for 3 and 10m which are 10 dB apart and
not 10.45dB apart if you extrapolate using 20LogD)
  * ANSI 63-4:2014 instructs you to extrapolate the results

If the standard or test method doesn’t specify, I guess the
important thing is to be clear in the report as to what’s been done.

Regards

Charlie

*Charlie Blackham*

*Sulis Consultants Ltd*

*Tel: +44 (0)7946 624317*

*Web: https://sulisconsultants.com/ *

Registered in England and Wales, number 05466247

*From:* itl-emc user group 

*Sent:* 28 October 2019 06:37
*To:* EMC-PSTC@LISTSERV.IEEE.ORG 
*Subject:* [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the
frequency range of 30-1000 MHz for test distance greater than 3 or
10 meters.

Testing is normally performed at either 3 meters or 10 meters on
an Open Area Test Site.

A question has arisen concerning reporting the test results in
these cases.

Any opinions concerning which should be converted:

a.Convert the limit to the relevant test distance (3 meters or 10
meters) by adding correction factor or

b.Convert the reading to the unit and test distance listed in the
standard (convert dBµV to µV and add correction factor for distance)

On some occasions I have seen option b. above used.

Which option is preferable?

All opinions welcome

*Regards,*

*David Shidlowsky***| Technical Reviewer

*Address*1 Bat-Sheva St. LOD 7120101 Israel

*Tel*972-8-9186113*Fax* 972-8-9153101

*Mail*: dav...@itlglobal.org
/dav...@itl.co.il
/e...@itl.co.il *Web* www.itlglobal.org


*/ITL Waze: /*https://waze.com/ul/hsv8vccn2j

*Fill out CustomerSatisfaction Survey*


*/Global Certifications You Can Trust /*

This e-mail message may contain privileged or confidential
information.

If you are not the intended recipient, you may not disclose, use,
disseminate, distribute, copy or rely upon this message or
attachment in any way. If you received this e-mail message in
error, please return by forwarding the message and its attachments
to the sender.

-


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 to mailto:emc-p...@ieee.org>>

All emc-pstc postings are archived and searchable on the web at:
http://www.ieee-pses.org/emc-pstc.html


Attachments are not permitted but the IEEE PSES Online Communities
site at http://product-compliance.oc.ieee.org/
 can be used for 

Re: [PSES] Reading or Limit Conversion?

[Douglas Powell]

David,

In my experience, I've found that nearly all test houses accept the
interpolated results. That said, the 3-meter measurement is understood to
have near field issues at frequencies on the low end. Also, the 3-meter
test needs to be performed in a chamber which has been tested for a uniform
field over the frequency range in question. Otherwise, the best you can
hope for is results considered only for pre-compliance and a final test in
a fully qualified chamber is needed. In any case, you will need to factor
in uncertainties and allow for a minimum passing margin, typically from 3
to 6 dBuV.

Best of luck, Doug

---
*I'm here to help you succeed! Feel free to contact me with any questions
related to product safety, certifications, risk assessment, or EMI ... at
no obligation. I'm always happy to help!*

Douglas E Powell
*Vertex Compliance Consulting*
Laporte, Colorado USA
970-646-3732
doug...@ieee.org
doug...@gmail.com 
http://www.linkedin.com/in/dougp01


On Mon, Oct 28, 2019 at 2:48 PM Grasso, Charles 
wrote:

> Take the reading. It’s the only way to be sure..
>
>
>
> It is not unusual for a product to pass @ 3m and then fail at 10m (or vice
> versa).
>
>
>
> Thanks!
>
>
>
> Charles Grasso
>
> W: 303-706-5467
>
>
>
> *From:* John Woodgate [mailto:j...@woodjohn.uk]
> *Sent:* Monday, October 28, 2019 1:30 AM
> *To:* EMC-PSTC@LISTSERV.IEEE.ORG
> *Subject:* Re: [PSES] Reading or Limit Conversion?
>
>
>
>  This message originated outside of DISH and was sent by:
> owner-emc-p...@listserv.ieee.org
>
> This inconsistency (in the underlying CISPR standards) should be addressed
> by CISPR, but it is difficult to get consensus whenever it is discussed.
>
> Best wishes
>
> John Woodgate OOO-Own Opinions Only
>
> J M Woodgate and Associates www.woodjohn.uk
>
> Rayleigh, Essex UK
>
> On 2019-10-28 07:05, Charlie Blackham wrote:
>
> David
>
>
>
> Hmm, different standards appear to deal with this differently:
>
>- EN 55011:2009 section 6.2.2.3 instructs you to normalise the
>measured data to the specified distance in the standard
>- EN 55032:2015 section 9 instructs you to adjust the limits (in fact
>it gives limits for 3 and 10m which are 10 dB apart and not 10.45dB apart
>if you extrapolate using 20LogD)
>- ANSI 63-4:2014 instructs you to extrapolate the results
>
>
>
> If the standard or test method doesn’t specify, I guess the important
> thing is to be clear in the report as to what’s been done.
>
>
>
> Regards
>
> Charlie
>
>
>
> *Charlie Blackham*
>
> *Sulis Consultants Ltd*
>
> *Tel: +44 (0)7946 624317*
>
> *Web: https://sulisconsultants.com/  *
>
> Registered in England and Wales, number 05466247
>
>
>
> *From:* itl-emc user group  
> *Sent:* 28 October 2019 06:37
> *To:* EMC-PSTC@LISTSERV.IEEE.ORG
> *Subject:* [PSES] Reading or Limit Conversion?
>
>
>
> A number of standards list radiated emission limits in the frequency range
> of 30-1000 MHz for test distance greater than 3 or 10 meters.
>
> Testing is normally performed at either 3 meters or 10 meters on an Open
> Area Test Site.
>
> A question has arisen concerning reporting the test results in these cases.
>
> Any opinions concerning which should be converted:
>
> a.   Convert the limit to the relevant test distance (3 meters or 10
> meters) by adding correction factor or
>
> b.  Convert the reading to the unit and test distance listed in the
> standard (convert dBµV to µV and add correction factor for distance)
>
> On some occasions I have seen option b. above used.
>
> Which option is preferable?
>
> All opinions welcome
>
>
>
> *Regards,*
>
> *David Shidlowsky* | Technical Reviewer
>
> *Address* 1 Bat-Sheva St. LOD 7120101 Israel
>
> *Tel* 972-8-9186113 *Fax* 972-8-9153101
>
> *Mail* : dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il  *Web*
> www.itlglobal.org
>
>
>
> *ITL Waze: *https://waze.com/ul/hsv8vccn2j
>
>
>
> *Fill out Customer* *Satisfaction Survey*
> 
>
> *Global Certifications You Can Trust *
>
> This e-mail message may contain privileged or confidential information.
>
> If you are not the intended recipient, you may not disclose, use,
> disseminate, distribute, copy or rely upon this message or attachment in
> any way. If you received this e-mail message in error, please return by
> forwarding the message and its attachments to the sender.
>
>
>
>
>
> -
> 
>
> 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 to <
> emc-p...@ieee.org>
>
> All emc-pstc postings are archived and searchable on the web at:
> http://www.ieee-pses.org/emc-pstc.html
>
> Attachments are not permitted but the IEEE PSES Online Communities site at
> http://product-compliance.oc.ieee.org/ can be used for graphics (in
> well-used 

Re: [PSES] Reading or Limit Conversion?

[Grasso, Charles]

Take the reading. It's the only way to be sure..

It is not unusual for a product to pass @ 3m and then fail at 10m (or vice 
versa).

Thanks!

Charles Grasso
W: 303-706-5467

From: John Woodgate [mailto:j...@woodjohn.uk]
Sent: Monday, October 28, 2019 1:30 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Reading or Limit Conversion?


 This message originated outside of DISH and was sent by: 
owner-emc-p...@listserv.ieee.org

This inconsistency (in the underlying CISPR standards) should be addressed by 
CISPR, but it is difficult to get consensus whenever it is discussed.

Best wishes

John Woodgate OOO-Own Opinions Only

J M Woodgate and Associates www.woodjohn.uk

Rayleigh, Essex UK
On 2019-10-28 07:05, Charlie Blackham wrote:
David

Hmm, different standards appear to deal with this differently:

  *   EN 55011:2009 section 6.2.2.3 instructs you to normalise the measured 
data to the specified distance in the standard
  *   EN 55032:2015 section 9 instructs you to adjust the limits (in fact it 
gives limits for 3 and 10m which are 10 dB apart and not 10.45dB apart if you 
extrapolate using 20LogD)
  *   ANSI 63-4:2014 instructs you to extrapolate the results

If the standard or test method doesn't specify, I guess the important thing is 
to be clear in the report as to what's been done.

Regards
Charlie

Charlie Blackham
Sulis Consultants Ltd
Tel: +44 (0)7946 624317
Web: https://sulisconsultants.com/
Registered in England and Wales, number 05466247

From: itl-emc user group 
Sent: 28 October 2019 06:37
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the frequency range of 
30-1000 MHz for test distance greater than 3 or 10 meters.
Testing is normally performed at either 3 meters or 10 meters on an Open Area 
Test Site.
A question has arisen concerning reporting the test results in these cases.
Any opinions concerning which should be converted:
a.   Convert the limit to the relevant test distance (3 meters or 10 
meters) by adding correction factor or
b.  Convert the reading to the unit and test distance listed in the 
standard (convert dBµV to µV and add correction factor for distance)
On some occasions I have seen option b. above used.
Which option is preferable?
All opinions welcome

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web www.itlglobal.org

[cid:image001.png@01D58D9E.A73400D0]ITL Waze: https://waze.com/ul/hsv8vccn2j

Fill out Customer Satisfaction 
Survey
Global Certifications You Can Trust
This e-mail message may contain privileged or confidential information.
If you are not the intended recipient, you may not disclose, use, disseminate, 
distribute, copy or rely upon this message or attachment in any way. If you 
received this e-mail message in error, please return by forwarding the message 
and its attachments to the sender.


-


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 to 
mailto:emc-p...@ieee.org>>

All emc-pstc postings are archived and searchable on the web at: 
http://www.ieee-pses.org/emc-pstc.html

Attachments are not permitted but the IEEE PSES Online Communities site at 
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used 
formats), large files, etc.

Website: http://www.ieee-pses.org/
Instructions: http://www.ieee-pses.org/list.html (including how to 
unsubscribe)
List rules: http://www.ieee-pses.org/listrules.html

For help, send mail to the list administrators:
Scott Douglas mailto:sdoug...@ieee.org>>
Mike Cantwell mailto:mcantw...@ieee.org>>

For policy questions, send mail to:
Jim Bacher mailto:j.bac...@ieee.org>>
David Heald mailto:dhe...@gmail.com>>
-


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 to 
mailto:emc-p...@ieee.org>>

All emc-pstc postings are archived and searchable on the web at: 
http://www.ieee-pses.org/emc-pstc.html

Attachments are not permitted but the IEEE PSES Online Communities site at 
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used 
formats), large files, etc.

Website: http://www.ieee-pses.org/
Instructions: http://www.ieee-pses.org/list.html (including how to 
unsubscribe)
List rules: 

Re: [PSES] Accredited lab for FCC testing

[Charlie Blackham]

The lab doesn't need to be accredited for SDoC, though the testing laboratory 
used is required to maintain a description of the test facility, as required by 
Section 2.948(b)
https://www.fcc.gov/testing-laboratory-qualifications

regards
Charlie

Charlie Blackham
Sulis Consultants Ltd
Tel: +44 (0)7946 624317
Web: https://sulisconsultants.com/
Registered in England and Wales, number 05466247

From: Paasche, Dieter 
Sent: 28 October 2019 15:53
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Accredited lab for FCC testing

Dear members,

Is it absolutely mandatory to test a product for EMC in an accredited lab under 
the suppliers declaration of conformity? If yes, where does it clearly say?
This is what I found so far. It seem to me that it does not necessarily need to 
be accredited, but would need to comply with all the accreditation 
requirements. The question comes from the "upon request" of the sentence in 
section 2.948 (2).

And therefore, I would be OK for the FCC, if I know that the test results of a 
non-accredited lab that follows the test site calibration as per standards are 
equivalent to an accredited lab. Is that correct?

§15.31   Measurement standards.
(d) Field strength measurements shall be made, to the extent possible, on an 
open area test site. Test sites other than open area test sites may be employed 
if they are properly calibrated so that the measurement results correspond to 
what would be obtained from an open area test site.

§2.948   Measurement facilities.
(b) A laboratory that makes measurements of equipment subject to an equipment 
authorization under the certification procedure or Supplier's Declaration of 
Conformity shall compile a description of the measurement facilities employed.

(1) The description of the measurement facilities shall contain the following 
information:

(i) Location of the test site.

(ii) Physical description of the test site accompanied by photographs that 
clearly show the details of the test site.

(iii) A drawing showing the dimensions of the site, physical layout of all 
supporting structures, and all structures within 5 times the distance between 
the measuring antenna and the device being measured.

(iv) Description of structures used to support the device being measured and 
the test instrumentation.

(v) List of measuring equipment used.

(vi) Information concerning the calibration of the measuring equipment, i.e., 
the date the equipment was last calibrated and how often the equipment is 
calibrated.

(vii) For a measurement facility that will be used for testing radiated 
emissions, a plot of site attenuation data taken pursuant to paragraph (d) of 
this section.

(2) The description of the measurement facilities shall be provided to a 
laboratory accreditation body upon request.


Sincerely,

Dieter Paasche
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[PSES] Accredited lab for FCC testing

[Paasche, Dieter]

Dear members,

Is it absolutely mandatory to test a product for EMC in an accredited lab under 
the suppliers declaration of conformity? If yes, where does it clearly say?
This is what I found so far. It seem to me that it does not necessarily need to 
be accredited, but would need to comply with all the accreditation 
requirements. The question comes from the "upon request" of the sentence in 
section 2.948 (2).

And therefore, I would be OK for the FCC, if I know that the test results of a 
non-accredited lab that follows the test site calibration as per standards are 
equivalent to an accredited lab. Is that correct?

§15.31   Measurement standards.
(d) Field strength measurements shall be made, to the extent possible, on an 
open area test site. Test sites other than open area test sites may be employed 
if they are properly calibrated so that the measurement results correspond to 
what would be obtained from an open area test site.

§2.948   Measurement facilities.
(b) A laboratory that makes measurements of equipment subject to an equipment 
authorization under the certification procedure or Supplier's Declaration of 
Conformity shall compile a description of the measurement facilities employed.

(1) The description of the measurement facilities shall contain the following 
information:

(i) Location of the test site.

(ii) Physical description of the test site accompanied by photographs that 
clearly show the details of the test site.

(iii) A drawing showing the dimensions of the site, physical layout of all 
supporting structures, and all structures within 5 times the distance between 
the measuring antenna and the device being measured.

(iv) Description of structures used to support the device being measured and 
the test instrumentation.

(v) List of measuring equipment used.

(vi) Information concerning the calibration of the measuring equipment, i.e., 
the date the equipment was last calibrated and how often the equipment is 
calibrated.

(vii) For a measurement facility that will be used for testing radiated 
emissions, a plot of site attenuation data taken pursuant to paragraph (d) of 
this section.

(2) The description of the measurement facilities shall be provided to a 
laboratory accreditation body upon request.


Sincerely,

Dieter Paasche

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Re: [PSES] [EXTERNAL] Re: [PSES] Reading or Limit Conversion?

[Sykes, Bob]

Also see the FCC Rules.  Part 15.31 (f) has additional guidance.
-Bob


From: Charlie Blackham [mailto:char...@sulisconsultants.com]
Sent: Monday, October 28, 2019 3:05 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [EXTERNAL] Re: [PSES] Reading or Limit Conversion?


CAUTION: This email originated from outside of the organization. Do not click 
links or open attachments unless you recognize the sender and know the content 
is safe.


David

Hmm, different standards appear to deal with this differently:

  *   EN 55011:2009 section 6.2.2.3 instructs you to normalise the measured 
data to the specified distance in the standard
  *   EN 55032:2015 section 9 instructs you to adjust the limits (in fact it 
gives limits for 3 and 10m which are 10 dB apart and not 10.45dB apart if you 
extrapolate using 20LogD)
  *   ANSI 63-4:2014 instructs you to extrapolate the results

If the standard or test method doesn't specify, I guess the important thing is 
to be clear in the report as to what's been done.

Regards
Charlie

Charlie Blackham
Sulis Consultants Ltd
Tel: +44 (0)7946 624317
Web: 
https://sulisconsultants.com/
Registered in England and Wales, number 05466247

From: itl-emc user group mailto:itl...@itl.co.il>>
Sent: 28 October 2019 06:37
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the frequency range of 
30-1000 MHz for test distance greater than 3 or 10 meters.
Testing is normally performed at either 3 meters or 10 meters on an Open Area 
Test Site.
A question has arisen concerning reporting the test results in these cases.
Any opinions concerning which should be converted:
a.   Convert the limit to the relevant test distance (3 meters or 10 
meters) by adding correction factor or
b.   Convert the reading to the unit and test distance listed in the 
standard (convert dBµV to µV and add correction factor for distance)
On some occasions I have seen option b. above used.
Which option is preferable?
All opinions welcome

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web 
www.itlglobal.org

[cid:image001.png@01D58D6E.267E5470]ITL Waze: 
https://waze.com/ul/hsv8vccn2j

Fill out Customer Satisfaction 
Survey
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This e-mail message may contain privileged or confidential information.
If you are not the intended recipient, you may not disclose, use, disseminate, 
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 can be used for graphics (in well-used formats), large files, etc.

Website: 

Re: [PSES] Reading or Limit Conversion?

[John Woodgate]

This inconsistency (in the underlying CISPR standards) should be 
addressed by CISPR, but it is difficult to get consensus whenever it is 
discussed.


Best wishes
John Woodgate OOO-Own Opinions Only
J M Woodgate and Associates www.woodjohn.uk
Rayleigh, Essex UK

On 2019-10-28 07:05, Charlie Blackham wrote:


David

Hmm, different standards appear to deal with this differently:

  * EN 55011:2009 section 6.2.2.3 instructs you to normalise the
measured data to the specified distance in the standard
  * EN 55032:2015 section 9 instructs you to adjust the limits (in
fact it gives limits for 3 and 10m which are 10 dB apart and not
10.45dB apart if you extrapolate using 20LogD)
  * ANSI 63-4:2014 instructs you to extrapolate the results

If the standard or test method doesn’t specify, I guess the important 
thing is to be clear in the report as to what’s been done.


Regards

Charlie

*Charlie Blackham*

*Sulis Consultants Ltd*

*Tel: +44 (0)7946 624317*

*Web: https://sulisconsultants.com/ *

Registered in England and Wales, number 05466247

*From:*itl-emc user group 
*Sent:* 28 October 2019 06:37
*To:* EMC-PSTC@LISTSERV.IEEE.ORG
*Subject:* [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the frequency 
range of 30-1000 MHz for test distance greater than 3 or 10 meters.


Testing is normally performed at either 3 meters or 10 meters on an 
Open Area Test Site.


A question has arisen concerning reporting the test results in these 
cases.


Any opinions concerning which should be converted:

 1. Convert the limit to the relevant test distance (3 meters or 10
meters) by adding correction factor or
 2. Convert the reading to the unit and test distance listed in the
standard (convert dBµV to µV and add correction factor for distance)

On some occasions I have seen option b. above used.

Which option is preferable?

All opinions welcome

*Regards,*

*David Shidlowsky***| Technical Reviewer

*Address*1 Bat-Sheva St. LOD 7120101 Israel

*Tel*972-8-9186113*Fax* 972-8-9153101

*Mail*: dav...@itlglobal.org 
/dav...@itl.co.il 
/e...@itl.co.il *Web* www.itlglobal.org 



*/ITL Waze: /*https://waze.com/ul/hsv8vccn2j

*Fill out CustomerSatisfaction Survey* 



*/Global Certifications You Can Trust /*

This e-mail message may contain privileged or confidential information.

If you are not the intended recipient, you may not disclose, use, 
disseminate, distribute, copy or rely upon this message or attachment 
in any way. If you received this e-mail message in error, please 
return by forwarding the message and its attachments to the sender.


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site at http://product-compliance.oc.ieee.org/ 
 can be used for graphics (in 
well-used formats), large files, etc.


Website: http://www.ieee-pses.org/
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List rules: http://www.ieee-pses.org/listrules.html

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list. To post a message to the list, send your e-mail to 

All emc-pstc postings are archived 

Re: [PSES] Reading or Limit Conversion?

[Charlie Blackham]

David

Hmm, different standards appear to deal with this differently:

  *   EN 55011:2009 section 6.2.2.3 instructs you to normalise the measured 
data to the specified distance in the standard
  *   EN 55032:2015 section 9 instructs you to adjust the limits (in fact it 
gives limits for 3 and 10m which are 10 dB apart and not 10.45dB apart if you 
extrapolate using 20LogD)
  *   ANSI 63-4:2014 instructs you to extrapolate the results

If the standard or test method doesn't specify, I guess the important thing is 
to be clear in the report as to what's been done.

Regards
Charlie

Charlie Blackham
Sulis Consultants Ltd
Tel: +44 (0)7946 624317
Web: https://sulisconsultants.com/
Registered in England and Wales, number 05466247

From: itl-emc user group 
Sent: 28 October 2019 06:37
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Reading or Limit Conversion?

A number of standards list radiated emission limits in the frequency range of 
30-1000 MHz for test distance greater than 3 or 10 meters.
Testing is normally performed at either 3 meters or 10 meters on an Open Area 
Test Site.
A question has arisen concerning reporting the test results in these cases.
Any opinions concerning which should be converted:

  1.  Convert the limit to the relevant test distance (3 meters or 10 meters) 
by adding correction factor or
  2.  Convert the reading to the unit and test distance listed in the standard 
(convert dBµV to µV and add correction factor for distance)
On some occasions I have seen option b. above used.
Which option is preferable?
All opinions welcome

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web www.itlglobal.org

[cid:image001.png@01D58D5D.1C5783B0]ITL Waze: https://waze.com/ul/hsv8vccn2j

Fill out Customer Satisfaction 
Survey
Global Certifications You Can Trust
This e-mail message may contain privileged or confidential information.
If you are not the intended recipient, you may not disclose, use, disseminate, 
distribute, copy or rely upon this message or attachment in any way. If you 
received this e-mail message in error, please return by forwarding the message 
and its attachments to the sender.


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All emc-pstc postings are archived and searchable on the web at:
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Attachments are not permitted but the IEEE PSES Online Communities site at 
http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used 
formats), large files, etc.

Website:  http://www.ieee-pses.org/
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[PSES] Reading or Limit Conversion?

[itl-emc user group]

A number of standards list radiated emission limits in the frequency range of 
30-1000 MHz for test distance greater than 3 or 10 meters.
Testing is normally performed at either 3 meters or 10 meters on an Open Area 
Test Site.
A question has arisen concerning reporting the test results in these cases.
Any opinions concerning which should be converted:

  1.  Convert the limit to the relevant test distance (3 meters or 10 meters) 
by adding correction factor or
  2.  Convert the reading to the unit and test distance listed in the standard 
(convert dBµV to µV and add correction factor for distance)
On some occasions I have seen option b. above used.
Which option is preferable?
All opinions welcome

Regards,
David Shidlowsky | Technical Reviewer
Address 1 Bat-Sheva St. LOD 7120101 Israel
Tel 972-8-9186113 Fax 972-8-9153101
Mail : 
dav...@itlglobal.org/dav...@itl.co.il/e...@itl.co.il
  Web www.itlglobal.org

[cid:image001.png@01D58D6A.EBD5E110] ITL Waze: https://waze.com/ul/hsv8vccn2j

Fill out Customer Satisfaction 
Survey
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This e-mail message may contain privileged or confidential information.
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