Re: [PSES] Measurement Accuracy

[John Woodgate]

Which standard has that very sensible text?

With best wishes DESIGN IT IN! OOO – Own Opinions Only
www.jmwa.demon.co.uk J M Woodgate and Associates Rayleigh England

Sylvae in aeternum manent.


-Original Message-
From: Balmukund Vyas [mailto:balmukund.v...@ymllabs.com] 
Sent: Thursday, September 22, 2016 5:05 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

It might be worth mentioning the text from one of the safety standard as below :
If, when carrying out a conformity test, there is any uncertainty about the 
exact value of an applied or measured quantity (for example, voltage) due to 
the tolerance:
a) the manufacturer should ensure that at least the specified test value is 
applied;
b) the test house should ensure that no more than the specified test value is 
applied.

B M Vyas

-Original Message-
From: Brian O'Connell [mailto:oconne...@tamuracorp.com]
Sent: Wednesday, September 21, 2016 11:05 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

Incorrect for product safety, there would be no 'gray area'. Per the error 
band, the temperature measurement exceeds limits. It is important to not 
confuse the 'accuracy method' in Guide 115 with the calculated UoM. Limits per 
instrument accuracy are only part of measurement uncertainty, and in fact, 
Guide 115 specifically indicates that if the uncertainty affects compliance 
with specification limits, the UoM calculation is the appropriate method for 
error bands.

For EMC - it is all magic and hand-waving, and your ability to concoct an 
engineering rationale in the report.

My favorite challenge to NRTLs is to demonstrate that their repeating error 
repeatability of measurement (type A) has normal distribution.

Brian


From: Balmukund Vyas [mailto:balmukund.v...@ymllabs.com]
Sent: Tuesday, September 20, 2016 9:17 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

in general, the test standards prescribe the accuracy / type of equipments and  
method to be used for testing. This means that measurement uncertainty has been 
specified indirectly. In such cases, where we are following these guidelines, 
the pass/fail decision can be taken based on the limits given in standard , 
without taking into account the uncertainty. If any of these guidelines are not 
being followed and resulting in higher uncertainty, the decision of pass/ fail 
needs to taken after due consideration of measurement uncertainty.
More and more standards are now defining uncertainty factors in details for 
example EMC standards; however I agree that many are still not very clear, 
requiring engineering judgment to be taken.

Best regards

B M Vyas

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si]
Sent: Wednesday, September 21, 2016 9:22 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

Measurement uncertainty depends on instruments used, method used etc. Each lab 
has to do calculation of measurement uncertainty for particular method. 
Measurement uncertainty becomes critical when results are close to the limit.

High uncertainty means you have more chance to be in »a grey area« where result 
needs to be defined as pass or fail. Laboratory needs to inform the client 
about value of measurement uncertainty if requested.

Example, if your measurement uncertainty of temperature measurement method with 
thermocouples is 3°C, limit according to standard is 85°C and you measure 84°C 
then you are in a grey area. In this case you can make result as Pass however 
client needs to be informed about your measurement uncertainty.


ISO GUIDE 115 give you some guidance how to do calculation, but no document 
specifies limits of measurement uncertainty.

Hope it helps.

Best regards,
Bostjan

From: Brian O'Connell [mailto:oconne...@tamuracorp.com]
Sent: Wednesday, September 21, 2016 12:54 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

ISO, International Standardization Organization, Guide to the Expression of 
Uncertainty in Measurement, GUM ISO, General Requirements for the Competence of 
testing and calibration laboratories, ISO 17025 
http://www.bipm.org/en/publications/guides/gum.html

Brian

From: Richard Nute [mailto:ri...@ieee.org]
Sent: Tuesday, September 20, 2016 1:18 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy



I was wondering if anyone was aware of any guidance documents that provided 
acceptable levels of uncertainty when conducting various tests.

I didn’t know what “uncertainty” is, so I did a Google search and found this 
reference:

https://www.wmo.int/pages/prog/gcos/documents/gruanmanuals/UK_NPL/mgpg11.pdf

Of particular interest is 1.2, which discusses “pass-fail.”  In both product 
safety and EMC compliance, the result is “pass” or “fail.”  The document says:

“Often, a test is not a measurement: tests normally lead to a ‘yes/no’ answer 
or a ‘pass/fail’ result. (However, measurements may be part 

Re: [PSES] Measurement Accuracy

[Balmukund Vyas]

It might be worth mentioning the text from one of the safety standard as below :
If, when carrying out a conformity test, there is any uncertainty about the 
exact value of an
applied or measured quantity (for example, voltage) due to the tolerance:
a) the manufacturer should ensure that at least the specified test value is 
applied;
b) the test house should ensure that no more than the specified test value is 
applied.

B M Vyas

-Original Message-
From: Brian O'Connell [mailto:oconne...@tamuracorp.com]
Sent: Wednesday, September 21, 2016 11:05 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

Incorrect for product safety, there would be no 'gray area'. Per the error 
band, the temperature measurement exceeds limits. It is important to not 
confuse the 'accuracy method' in Guide 115 with the calculated UoM. Limits per 
instrument accuracy are only part of measurement uncertainty, and in fact, 
Guide 115 specifically indicates that if the uncertainty affects compliance 
with specification limits, the UoM calculation is the appropriate method for 
error bands.

For EMC - it is all magic and hand-waving, and your ability to concoct an 
engineering rationale in the report.

My favorite challenge to NRTLs is to demonstrate that their repeating error 
repeatability of measurement (type A) has normal distribution.

Brian


From: Balmukund Vyas [mailto:balmukund.v...@ymllabs.com]
Sent: Tuesday, September 20, 2016 9:17 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

in general, the test standards prescribe the accuracy / type of equipments and  
method to be used for testing. This means that measurement uncertainty has been 
specified indirectly. In such cases, where we are following these guidelines, 
the pass/fail decision can be taken based on the limits given in standard , 
without taking into account the uncertainty. If any of these guidelines are not 
being followed and resulting in higher uncertainty, the decision of pass/ fail 
needs to taken after due consideration of measurement uncertainty.
More and more standards are now defining uncertainty factors in details for 
example EMC standards; however I agree that many are still not very clear, 
requiring engineering judgment to be taken.

Best regards

B M Vyas

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si]
Sent: Wednesday, September 21, 2016 9:22 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

Measurement uncertainty depends on instruments used, method used etc. Each lab 
has to do calculation of measurement uncertainty for particular method. 
Measurement uncertainty becomes critical when results are close to the limit.

High uncertainty means you have more chance to be in »a grey area« where result 
needs to be defined as pass or fail. Laboratory needs to inform the client 
about value of measurement uncertainty if requested.

Example, if your measurement uncertainty of temperature measurement method with 
thermocouples is 3°C, limit according to standard is 85°C and you measure 84°C 
then you are in a grey area. In this case you can make result as Pass however 
client needs to be informed about your measurement uncertainty.


ISO GUIDE 115 give you some guidance how to do calculation, but no document 
specifies limits of measurement uncertainty.

Hope it helps.

Best regards,
Bostjan

From: Brian O'Connell [mailto:oconne...@tamuracorp.com]
Sent: Wednesday, September 21, 2016 12:54 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

ISO, International Standardization Organization, Guide to the Expression of 
Uncertainty in Measurement, GUM
ISO, General Requirements for the Competence of testing and calibration 
laboratories, ISO 17025
http://www.bipm.org/en/publications/guides/gum.html

Brian

From: Richard Nute [mailto:ri...@ieee.org]
Sent: Tuesday, September 20, 2016 1:18 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy



I was wondering if anyone was aware of any guidance documents that provided 
acceptable levels of uncertainty when conducting various tests.

I didn’t know what “uncertainty” is, so I did a Google search and found this 
reference:

https://www.wmo.int/pages/prog/gcos/documents/gruanmanuals/UK_NPL/mgpg11.pdf

Of particular interest is 1.2, which discusses “pass-fail.”  In both product 
safety and EMC compliance, the result is “pass” or “fail.”  The document says:

“Often, a test is not a measurement: tests normally lead to a ‘yes/no’ answer 
or a ‘pass/fail’ result. (However, measurements may be part of the process 
leading up to a test result.)”

So, our standards specify tests and test limits, pass or fail.

Just looking for some additional guidance documents or standards that would 
help me convince the powers that be that such errors are unacceptable.

Well, according to the document, you need to take into account what you call 
“errors” as they are not errors but different measurements t

Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Richard Nute]

 

 

Hi Pete:  

 

Are the non-copyrighted papers (such as the UL “Bulletins of Research”) in the 
TC64/WG4 library available for public distribution?

 

Rich

 

 

From: Pete Perkins [mailto:0061f3f32d0c-dmarc-requ...@ieee.org] 
Sent: Wednesday, September 21, 2016 2:29 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

Doug, et al,

 

This fine early work is the foundation for later workers such 
as Dalziel, etc. which provides the basis for understanding electric shock 
effects.  Note that you can only download the whole, very clear copy if your 
organization has a membership in the digital library in which this copy is 
stored.   

 

Papers such as these are the central core of work that is the 
basis for the development of IEC 60479 series which deals with the effects of 
electric shock on the human body.   That group, IEC TC64/WG4, has a library of 
these important basic papers (including the Whittaker paper referenced here) 
which is used for reference in their work.

 

Thanx to Rich for summarizing this paper.  

 

:>) br,  Pete

 

Peter E Perkins, PE

Principal Product Safety & Regulatory Affairs Consultant

PO Box 23427

Tigard, ORe  97281-3427

 

503/452-1201

 

  p.perk...@ieee.org

 


-

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

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Mike Cantwell 

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

Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Nyffenegger, Dave]

Likely yes but that requirement was probably grandfathered for the pool built 
in 1979.  Regular inspections are required of public pools in NC but electrical 
inspection is not required (except for new permits.)  We’ll see if any change 
for legacy pools comes of this.

-Dave

From: Ed Price [mailto:edpr...@cox.net]
Sent: Wednesday, September 21, 2016 8:24 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

It would appear that the real problem was lack of a GFCI breaker on the motor 
circuit, which would have tripped open when the current in/out ratio became 
unbalanced.

Ed Price
WB6WSN
Chula Vista, CA USA

From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com]
Sent: Wednesday, September 21, 2016 4:42 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

Well here’s one recent electric shock effect, the cause of which may be more 
interesting to understand than the resulting death.

http://www.newsobserver.com/news/state/north-carolina/article101748857.html

Tragic death of a lifeguard getting electrocuted while reaching into the pool 
and then probably being incapacitated and drowning.  The published laymen’s 
cause was due to a faulty pump motor that did not trip the circuit breaker due 
to a corroded wire.  Bad bonding connection I assume.  Imagine if the failure 
had occurred with a pool full of swimmers.

-Dave


From: Pete Perkins [mailto:0061f3f32d0c-dmarc-requ...@ieee.org]
Sent: Wednesday, September 21, 2016 5:29 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

Doug, et al,

This fine early work is the foundation for later workers such 
as Dalziel, etc. which provides the basis for understanding electric shock 
effects.  Note that you can only download the whole, very clear copy if your 
organization has a membership in the digital library in which this copy is 
stored.

Papers such as these are the central core of work that is the 
basis for the development of IEC 60479 series which deals with the effects of 
electric shock on the human body.   That group, IEC TC64/WG4, has a library of 
these important basic papers (including the Whittaker paper referenced here) 
which is used for reference in their work.

Thanx to Rich for summarizing this paper.

:>) br,  Pete

Peter E Perkins, PE
Principal Product Safety & Regulatory Affairs Consultant
PO Box 23427
Tigard, ORe  97281-3427

503/452-1201

p.perk...@ieee.org

From: Douglas Nix [mailto:d...@mac.com]
Sent: Wednesday, September 21, 2016 12:32 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

You can view a good quality copy of this seminal work online at

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3

--
Doug Nix
d...@mac.com
(519) 729-5704

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.
  - Dr. Seuss

On 21-Sep-16, at 13:52, Richard Nute mailto:ri...@ieee.org>> 
wrote:


Underwriters Laboratories did basic research in the field of safety and 
published the results of that research in a series of “Bulletins of Research.” 
At least 58 bulletins were published relating to fire, explosion, and electric 
shock.
One of those Bulletins, “Electric Shock as it Pertains to the Electric Fence,” 
is a classic document in the field of product safety. The research was 
performed from 1936 to 1939 by Baron Whitaker, an Assistant Electrical Engineer 
at UL. Whitaker ultimately ascended to the presidency of UL.
Whitaker’s research still stands today. While similar research has been done in 
support of modern IEC publications, such research is usually published only in 
IEC committee papers and is usually highly focused towards the specific 
standard or report the IEC is attempting to write.
This UL Bulletin of Research on the electric fence contains much information 
that applies to much more than just the electric fence. This is why it is a 
classic work.
Whitaker wanted to determine the maximum value of current, for both ac and dc, 
the frequency, and the duration that “can be considered as not being hazardous 
to human life.”
Whitaker undertook to determine values for:
1.  Body electrical resistance
2.  Safe open-circuit voltage.
3.  Effects of dc, interrupted dc, ac, and frequency of ac.
4.  The maximum current and duration which will not cause bodily injury.
5.  The minimum off time.
https://www.prisonlegalnews.org/media/publications/taser_ul_electric_shock_analysis_1955.pdf

Rich

-

This message is from the IEEE Product Safety Engineering Society emc-pstc 
discussion list. To post a message t

Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Ed Price]

It would appear that the real problem was lack of a GFCI breaker on the motor 
circuit, which would have tripped open when the current in/out ratio became 
unbalanced.

 

Ed Price
WB6WSN
Chula Vista, CA USA

 

From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com] 
Sent: Wednesday, September 21, 2016 4:42 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

Well here’s one recent electric shock effect, the cause of which may be more 
interesting to understand than the resulting death.

 

http://www.newsobserver.com/news/state/north-carolina/article101748857.html

 

Tragic death of a lifeguard getting electrocuted while reaching into the pool 
and then probably being incapacitated and drowning.  The published laymen’s 
cause was due to a faulty pump motor that did not trip the circuit breaker due 
to a corroded wire.  Bad bonding connection I assume.  Imagine if the failure 
had occurred with a pool full of swimmers.

 

-Dave

 

 

From: Pete Perkins [mailto:0061f3f32d0c-dmarc-requ...@ieee.org] 
Sent: Wednesday, September 21, 2016 5:29 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

Doug, et al,

 

This fine early work is the foundation for later workers such 
as Dalziel, etc. which provides the basis for understanding electric shock 
effects.  Note that you can only download the whole, very clear copy if your 
organization has a membership in the digital library in which this copy is 
stored.   

 

Papers such as these are the central core of work that is the 
basis for the development of IEC 60479 series which deals with the effects of 
electric shock on the human body.   That group, IEC TC64/WG4, has a library of 
these important basic papers (including the Whittaker paper referenced here) 
which is used for reference in their work.

 

Thanx to Rich for summarizing this paper.  

 

:>) br,  Pete

 

Peter E Perkins, PE

Principal Product Safety & Regulatory Affairs Consultant

PO Box 23427

Tigard, ORe  97281-3427

 

503/452-1201

 

  p.perk...@ieee.org

 

From: Douglas Nix [mailto:d...@mac.com] 
Sent: Wednesday, September 21, 2016 12:32 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

You can view a good quality copy of this seminal work online at

 

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3

 

--

Doug Nix

d...@mac.com

(519) 729-5704

 

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.

  - Dr. Seuss

 

On 21-Sep-16, at 13:52, Richard Nute  wrote:

 

 

Underwriters Laboratories did basic research in the field of safety and 
published the results of that research in a series of “Bulletins of Research.” 
At least 58 bulletins were published relating to fire, explosion, and electric 
shock. 

One of those Bulletins, “Electric Shock as it Pertains to the Electric Fence,” 
is a classic document in the field of product safety. The research was 
performed from 1936 to 1939 by Baron Whitaker, an Assistant Electrical Engineer 
at UL. Whitaker ultimately ascended to the presidency of UL. 

Whitaker’s research still stands today. While similar research has been done in 
support of modern IEC publications, such research is usually published only in 
IEC committee papers and is usually highly focused towards the specific 
standard or report the IEC is attempting to write. 

This UL Bulletin of Research on the electric fence contains much information 
that applies to much more than just the electric fence. This is why it is a 
classic work.

Whitaker wanted to determine the maximum value of current, for both ac and dc, 
the frequency, and the duration that “can be considered as not being hazardous 
to human life.” 

Whitaker undertook to determine values for: 

1.  Body electrical resistance 

2.  Safe open-circuit voltage. 

3.  Effects of dc, interrupted dc, ac, and frequency of ac. 

4.  The maximum current and duration which will not cause bodily injury. 

5.  The minimum off time.

 

 
https://www.prisonlegalnews.org/media/publications/taser_ul_electric_shock_analysis_1955.pdf

 

Rich

 

-


This message is from the IEEE Product Safety Engineering Society emc-pstc 
discussion list. To post a message to the list, send your e-mail 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/
Instructi

Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Nyffenegger, Dave]

Well here’s one recent electric shock effect, the cause of which may be more 
interesting to understand than the resulting death.

http://www.newsobserver.com/news/state/north-carolina/article101748857.html

Tragic death of a lifeguard getting electrocuted while reaching into the pool 
and then probably being incapacitated and drowning.  The published laymen’s 
cause was due to a faulty pump motor that did not trip the circuit breaker due 
to a corroded wire.  Bad bonding connection I assume.  Imagine if the failure 
had occurred with a pool full of swimmers.

-Dave


From: Pete Perkins [mailto:0061f3f32d0c-dmarc-requ...@ieee.org]
Sent: Wednesday, September 21, 2016 5:29 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

Doug, et al,

This fine early work is the foundation for later workers such 
as Dalziel, etc. which provides the basis for understanding electric shock 
effects.  Note that you can only download the whole, very clear copy if your 
organization has a membership in the digital library in which this copy is 
stored.

Papers such as these are the central core of work that is the 
basis for the development of IEC 60479 series which deals with the effects of 
electric shock on the human body.   That group, IEC TC64/WG4, has a library of 
these important basic papers (including the Whittaker paper referenced here) 
which is used for reference in their work.

Thanx to Rich for summarizing this paper.

:>) br,  Pete

Peter E Perkins, PE
Principal Product Safety & Regulatory Affairs Consultant
PO Box 23427
Tigard, ORe  97281-3427

503/452-1201

p.perk...@ieee.org

From: Douglas Nix [mailto:d...@mac.com]
Sent: Wednesday, September 21, 2016 12:32 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

You can view a good quality copy of this seminal work online at

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3

--
Doug Nix
d...@mac.com
(519) 729-5704

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.
  - Dr. Seuss

On 21-Sep-16, at 13:52, Richard Nute mailto:ri...@ieee.org>> 
wrote:


Underwriters Laboratories did basic research in the field of safety and 
published the results of that research in a series of “Bulletins of Research.” 
At least 58 bulletins were published relating to fire, explosion, and electric 
shock.
One of those Bulletins, “Electric Shock as it Pertains to the Electric Fence,” 
is a classic document in the field of product safety. The research was 
performed from 1936 to 1939 by Baron Whitaker, an Assistant Electrical Engineer 
at UL. Whitaker ultimately ascended to the presidency of UL.
Whitaker’s research still stands today. While similar research has been done in 
support of modern IEC publications, such research is usually published only in 
IEC committee papers and is usually highly focused towards the specific 
standard or report the IEC is attempting to write.
This UL Bulletin of Research on the electric fence contains much information 
that applies to much more than just the electric fence. This is why it is a 
classic work.
Whitaker wanted to determine the maximum value of current, for both ac and dc, 
the frequency, and the duration that “can be considered as not being hazardous 
to human life.”
Whitaker undertook to determine values for:
1.  Body electrical resistance
2.  Safe open-circuit voltage.
3.  Effects of dc, interrupted dc, ac, and frequency of ac.
4.  The maximum current and duration which will not cause bodily injury.
5.  The minimum off time.
https://www.prisonlegalnews.org/media/publications/taser_ul_electric_shock_analysis_1955.pdf

Rich

-

This message is from the IEEE Product Safety Engineering Society emc-pstc 
discussion list. To post a message to the list, send your e-mail 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 lis

Re: [PSES] standard for power suply for server room.

[Douglas Nix]

All,

600 V is standard in Canada.

--
Doug Nix
d...@mac.com
http://www.dougnix.net


If you pick up a starving dog and make him prosperous, he will not bite you; 
that is the principal difference between a dog and a man. - Mark Twain 

> On 21-Sep-16, at 15:52, Richard Nute  wrote:
> 
>  
> I would seriously consider pointing out to your customer that their specified 
> supply voltage is not a common one
>  
> I suspect your customer already knows this.  The issue is determining that 
> the product is safe, given that the mains ratings exceed those in many safety 
> standards.  While standards such as 60950 state that they are applicable to 
> 600 V rms (there is a statement in the standard that unless otherwise noted, 
> all voltages are rms), as has been mentioned, the clearance, creepage, and 
> electric strength requirements go well beyond 600 V.  
>  
> Clearance and electric strength requirements are based on transient 
> overvoltages.  Transient overvoltages come from lightning strikes and 
> switching.  DC mains may not be outside the local building so may not be 
> subject to either or both of these sources of overvoltages, so the clearances 
> and electric strength requirements may not be applicable to this equipment.  
> I believe 62368 so states.
>  
> Rich
>  
>  
>  
> -
> 
> This message is from the IEEE Product Safety Engineering Society emc-pstc 
> discussion list. To post a message to the list, send your e-mail to 
> mailto:emc-p...@ieee.org>>
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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.
> 
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Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Pete Perkins]

Doug, et al,

 

This fine early work is the foundation for later workers such 
as Dalziel, etc. which provides the basis for understanding electric shock 
effects.  Note that you can only download the whole, very clear copy if your 
organization has a membership in the digital library in which this copy is 
stored.   

 

Papers such as these are the central core of work that is the 
basis for the development of IEC 60479 series which deals with the effects of 
electric shock on the human body.   That group, IEC TC64/WG4, has a library of 
these important basic papers (including the Whittaker paper referenced here) 
which is used for reference in their work.

 

Thanx to Rich for summarizing this paper.  

 

:>) br,  Pete

 

Peter E Perkins, PE

Principal Product Safety & Regulatory Affairs Consultant

PO Box 23427

Tigard, ORe  97281-3427

 

503/452-1201

 

  p.perk...@ieee.org

 

From: Douglas Nix [mailto:d...@mac.com] 
Sent: Wednesday, September 21, 2016 12:32 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

You can view a good quality copy of this seminal work online at

 

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3

 

--

Doug Nix

d...@mac.com  

(519) 729-5704

 

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.

  - Dr. Seuss

 

On 21-Sep-16, at 13:52, Richard Nute mailto:ri...@ieee.org> > 
wrote:

 

 

Underwriters Laboratories did basic research in the field of safety and 
published the results of that research in a series of “Bulletins of Research.” 
At least 58 bulletins were published relating to fire, explosion, and electric 
shock. 

One of those Bulletins, “Electric Shock as it Pertains to the Electric Fence,” 
is a classic document in the field of product safety. The research was 
performed from 1936 to 1939 by Baron Whitaker, an Assistant Electrical Engineer 
at UL. Whitaker ultimately ascended to the presidency of UL. 

Whitaker’s research still stands today. While similar research has been done in 
support of modern IEC publications, such research is usually published only in 
IEC committee papers and is usually highly focused towards the specific 
standard or report the IEC is attempting to write. 

This UL Bulletin of Research on the electric fence contains much information 
that applies to much more than just the electric fence. This is why it is a 
classic work.

Whitaker wanted to determine the maximum value of current, for both ac and dc, 
the frequency, and the duration that “can be considered as not being hazardous 
to human life.” 

Whitaker undertook to determine values for: 

1.  Body electrical resistance 

2.  Safe open-circuit voltage. 

3.  Effects of dc, interrupted dc, ac, and frequency of ac. 

4.  The maximum current and duration which will not cause bodily injury. 

5.  The minimum off time.

 

 
https://www.prisonlegalnews.org/media/publications/taser_ul_electric_shock_analysis_1955.pdf

 

Rich

 

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For

Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Douglas Nix]

You can view a good quality copy of this seminal work online at

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3 


--
Doug Nix
d...@mac.com
(519) 729-5704

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.
  - Dr. Seuss

> On 21-Sep-16, at 13:52, Richard Nute  wrote:
> 
> 
> Underwriters Laboratories did basic research in the field of safety and 
> published the results of that research in a series of “Bulletins of 
> Research.” At least 58 bulletins were published relating to fire, explosion, 
> and electric shock.
> One of those Bulletins, “Electric Shock as it Pertains to the Electric 
> Fence,” is a classic document in the field of product safety. The research 
> was performed from 1936 to 1939 by Baron Whitaker, an Assistant Electrical 
> Engineer at UL. Whitaker ultimately ascended to the presidency of UL.
> Whitaker’s research still stands today. While similar research has been done 
> in support of modern IEC publications, such research is usually published 
> only in IEC committee papers and is usually highly focused towards the 
> specific standard or report the IEC is attempting to write.
> This UL Bulletin of Research on the electric fence contains much information 
> that applies to much more than just the electric fence. This is why it is a 
> classic work.
> Whitaker wanted to determine the maximum value of current, for both ac and 
> dc, the frequency, and the duration that “can be considered as not being 
> hazardous to human life.”
> Whitaker undertook to determine values for:
> 1.  Body electrical resistance
> 2.  Safe open-circuit voltage.
> 3.  Effects of dc, interrupted dc, ac, and frequency of ac.
> 4.  The maximum current and duration which will not cause bodily injury.
> 5.  The minimum off time.
> https://www.prisonlegalnews.org/media/publications/taser_ul_electric_shock_analysis_1955.pdf
>  
> 
> 
> Rich
> 
> -
> 
> This message is from the IEEE Product Safety Engineering Society emc-pstc 
> discussion list. To post a message to the list, send your e-mail 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) 
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> 
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Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Richard Nute]

 

 

Hi Doug:

 

Thanks!  Any other Bulletins of Research sources?  Any topic.

 

Rich

 

 

From: Douglas Nix [mailto:d...@mac.com] 
Sent: Wednesday, September 21, 2016 12:32 PM
To: Rich Nute 
Cc: IEEE EMC PSTC 
Subject: Re: [PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

 

You can view a good quality copy of this seminal work online at

 

https://babel.hathitrust.org/cgi/pt?id=uc1.$b661851;view=1up;seq=3

 

--

Doug Nix

d...@mac.com  

(519) 729-5704

 

Be who you are and say what you feel, because those who mind don't matter and 
those who matter don't mind.

  - Dr. Seuss

 


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Re: [PSES] standard for power suply for server room.

[john Allen]

Rich & friends 

 

Whilst I generally agree with what you said, if the customer already knows the 
system to which he needs connections, then it is only reasonable to ask him to 
clarify what his requirements and constraints are!

 

I would also point out that other factors like altitude also affect dielectric 
strength tests  and so on so, please still ask the questions, or thereabouts.

 

John E Allen

W.London, UK

 

From: Richard Nute [mailto:ri...@ieee.org] 
Sent: 21 September 2016 20:52
To: 'john Allen'; EMC-PSTC@LISTSERV.IEEE.ORG
Subject: RE: [PSES] standard for power suply for server room.

 

 

I would seriously consider pointing out to your customer that their specified 
supply voltage is not a common one

 

I suspect your customer already knows this.  The issue is determining that the 
product is safe, given that the mains ratings exceed those in many safety 
standards.  While standards such as 60950 state that they are applicable to 600 
V rms (there is a statement in the standard that unless otherwise noted, all 
voltages are rms), as has been mentioned, the clearance, creepage, and electric 
strength requirements go well beyond 600 V.  

 

Clearance and electric strength requirements are based on transient 
overvoltages.  Transient overvoltages come from lightning strikes and 
switching.  DC mains may not be outside the local building so may not be 
subject to either or both of these sources of overvoltages, so the clearances 
and electric strength requirements may not be applicable to this equipment.  I 
believe 62368 so states.

 

Rich

 

 

 


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Re: [PSES] standard for power suply for server room.

[Richard Nute]

 

I would seriously consider pointing out to your customer that their specified 
supply voltage is not a common one

 

I suspect your customer already knows this.  The issue is determining that the 
product is safe, given that the mains ratings exceed those in many safety 
standards.  While standards such as 60950 state that they are applicable to 600 
V rms (there is a statement in the standard that unless otherwise noted, all 
voltages are rms), as has been mentioned, the clearance, creepage, and electric 
strength requirements go well beyond 600 V.  

 

Clearance and electric strength requirements are based on transient 
overvoltages.  Transient overvoltages come from lightning strikes and 
switching.  DC mains may not be outside the local building so may not be 
subject to either or both of these sources of overvoltages, so the clearances 
and electric strength requirements may not be applicable to this equipment.  I 
believe 62368 so states.

 

Rich

 

 

 


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[PSES] ELECTRIC SHOCK AS IT PERTAINS TO THE ELECTRIC FENCE

[Richard Nute]

Underwriters Laboratories did basic research in
the field of safety and published the results of
that research in a series of "Bulletins of
Research." At least 58 bulletins were published
relating to fire, explosion, and electric shock. 

One of those Bulletins, "Electric Shock as it
Pertains to the Electric Fence," is a classic
document in the field of product safety. The
research was performed from 1936 to 1939 by Baron
Whitaker, an Assistant Electrical Engineer at UL.
Whitaker ultimately ascended to the presidency of
UL. 

Whitaker's research still stands today. While
similar research has been done in support of
modern IEC publications, such research is usually
published only in IEC committee papers and is
usually highly focused towards the specific
standard or report the IEC is attempting to write.


This UL Bulletin of Research on the electric fence
contains much information that applies to much
more than just the electric fence. This is why it
is a classic work.

Whitaker wanted to determine the maximum value of
current, for both ac and dc, the frequency, and
the duration that "can be considered as not being
hazardous to human life." 

Whitaker undertook to determine values for: 

1.  Body electrical resistance 
2.  Safe open-circuit voltage. 
3.  Effects of dc, interrupted dc, ac, and
frequency of ac. 
4.  The maximum current and duration which
will not cause bodily injury. 
5.  The minimum off time.

https://www.prisonlegalnews.org/media/publications
/taser_ul_electric_shock_analysis_1955.pdf


Rich


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Re: [PSES] Measurement Accuracy

[Cortland Richmond]

On 9/21/2016 1:34 PM, Brian O'Connell wrote:

For EMC - it is all magic and hand-waving


Given reasonably well calibrated test equipment, for EMC it's "whose lab 
and how different they set up the test".


The magic is coming within 6 dB of each other.


Cortland Richmond

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Re: [PSES] Measurement Accuracy

[Brian O'Connell]

Incorrect for product safety, there would be no 'gray area'. Per the error 
band, the temperature measurement exceeds limits. It is important to not 
confuse the 'accuracy method' in Guide 115 with the calculated UoM. Limits per 
instrument accuracy are only part of measurement uncertainty, and in fact, 
Guide 115 specifically indicates that if the uncertainty affects compliance 
with specification limits, the UoM calculation is the appropriate method for 
error bands.

For EMC - it is all magic and hand-waving, and your ability to concoct an 
engineering rationale in the report.

My favorite challenge to NRTLs is to demonstrate that their repeating error 
repeatability of measurement (type A) has normal distribution.

Brian


From: Balmukund Vyas [mailto:balmukund.v...@ymllabs.com] 
Sent: Tuesday, September 20, 2016 9:17 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

in general, the test standards prescribe the accuracy / type of equipments and  
method to be used for testing. This means that measurement uncertainty has been 
specified indirectly. In such cases, where we are following these guidelines, 
the pass/fail decision can be taken based on the limits given in standard , 
without taking into account the uncertainty. If any of these guidelines are not 
being followed and resulting in higher uncertainty, the decision of pass/ fail 
needs to taken after due consideration of measurement uncertainty.
More and more standards are now defining uncertainty factors in details for 
example EMC standards; however I agree that many are still not very clear, 
requiring engineering judgment to be taken.
 
Best regards
 
B M Vyas
 
From: Boštjan Glavič [mailto:bostjan.gla...@siq.si] 
Sent: Wednesday, September 21, 2016 9:22 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy
 
Measurement uncertainty depends on instruments used, method used etc. Each lab 
has to do calculation of measurement uncertainty for particular method. 
Measurement uncertainty becomes critical when results are close to the limit.
 
High uncertainty means you have more chance to be in »a grey area« where result 
needs to be defined as pass or fail. Laboratory needs to inform the client 
about value of measurement uncertainty if requested.
 
Example, if your measurement uncertainty of temperature measurement method with 
thermocouples is 3°C, limit according to standard is 85°C and you measure 84°C 
then you are in a grey area. In this case you can make result as Pass however 
client needs to be informed about your measurement uncertainty.
 
 
ISO GUIDE 115 give you some guidance how to do calculation, but no document 
specifies limits of measurement uncertainty.
 
Hope it helps.
 
Best regards,
Bostjan
 
From: Brian O'Connell [mailto:oconne...@tamuracorp.com] 
Sent: Wednesday, September 21, 2016 12:54 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy
 
ISO, International Standardization Organization, Guide to the Expression of 
Uncertainty in Measurement, GUM
ISO, General Requirements for the Competence of testing and calibration 
laboratories, ISO 17025
http://www.bipm.org/en/publications/guides/gum.html
 
Brian
 
From: Richard Nute [mailto:ri...@ieee.org] 
Sent: Tuesday, September 20, 2016 1:18 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy
 
 
 
I was wondering if anyone was aware of any guidance documents that provided 
acceptable levels of uncertainty when conducting various tests.
 
I didn’t know what “uncertainty” is, so I did a Google search and found this 
reference:
 
https://www.wmo.int/pages/prog/gcos/documents/gruanmanuals/UK_NPL/mgpg11.pdf
 
Of particular interest is 1.2, which discusses “pass-fail.”  In both product 
safety and EMC compliance, the result is “pass” or “fail.”  The document says:
 
“Often, a test is not a measurement: tests normally lead to a ‘yes/no’ answer 
or a ‘pass/fail’ result. (However, measurements may be part of the process 
leading up to a test result.)”
 
So, our standards specify tests and test limits, pass or fail.  
 
Just looking for some additional guidance documents or standards that would 
help me convince the powers that be that such errors are unacceptable.
 
Well, according to the document, you need to take into account what you call 
“errors” as they are not errors but different measurements that need to be 
accounted for in determining the “pass-fail.”
 
At the end of the document are two references, which are much more detailed.
 
Rich
 

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Re: [PSES] Measurement Accuracy

[Nyffenegger, Dave]

I’ll add that in some cases the uncertainty may not lead to a pass/fail 
decision rather just a another data point to be considered with other 
measurements/calculations.  For example with the acoustics standards ISO 
7574-1,2,3,4, ISO 3740, ISO 3744, ISO 3746.

-Dave

From: Balmukund Vyas [mailto:balmukund.v...@ymllabs.com]
Sent: Wednesday, September 21, 2016 12:17 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

in general, the test standards prescribe the accuracy / type of equipments and  
method to be used for testing. This means that measurement uncertainty has been 
specified indirectly. In such cases, where we are following these guidelines, 
the pass/fail decision can be taken based on the limits given in standard , 
without taking into account the uncertainty. If any of these guidelines are not 
being followed and resulting in higher uncertainty, the decision of pass/ fail 
needs to taken after due consideration of measurement uncertainty.
More and more standards are now defining uncertainty factors in details for 
example EMC standards; however I agree that many are still not very clear, 
requiring engineering judgment to be taken.

Best regards

B M Vyas

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si]
Sent: Wednesday, September 21, 2016 9:22 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

Measurement uncertainty depends on instruments used, method used etc. Each lab 
has to do calculation of measurement uncertainty for particular method. 
Measurement uncertainty becomes critical when results are close to the limit.

High uncertainty means you have more chance to be in »a grey area« where result 
needs to be defined as pass or fail. Laboratory needs to inform the client 
about value of measurement uncertainty if requested.

Example, if your measurement uncertainty of temperature measurement method with 
thermocouples is 3°C, limit according to standard is 85°C and you measure 84°C 
then you are in a grey area. In this case you can make result as Pass however 
client needs to be informed about your measurement uncertainty.


ISO GUIDE 115 give you some guidance how to do calculation, but no document 
specifies limits of measurement uncertainty.

Hope it helps.

Best regards,
Bostjan

From: Brian O'Connell [mailto:oconne...@tamuracorp.com]
Sent: Wednesday, September 21, 2016 12:54 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

ISO, International Standardization Organization, Guide to the Expression of 
Uncertainty in Measurement, GUM
ISO, General Requirements for the Competence of testing and calibration 
laboratories, ISO 17025
http://www.bipm.org/en/publications/guides/gum.html

Brian

From: Richard Nute [mailto:ri...@ieee.org]
Sent: Tuesday, September 20, 2016 1:18 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy



I was wondering if anyone was aware of any guidance documents that provided 
acceptable levels of uncertainty when conducting various tests.

I didn’t know what “uncertainty” is, so I did a Google search and found this 
reference:

https://www.wmo.int/pages/prog/gcos/documents/gruanmanuals/UK_NPL/mgpg11.pdf

Of particular interest is 1.2, which discusses “pass-fail.”  In both product 
safety and EMC compliance, the result is “pass” or “fail.”  The document says:

“Often, a test is not a measurement: tests normally lead to a ‘yes/no’ answer 
or a ‘pass/fail’ result. (However, measurements may be part of the process 
leading up to a test result.)”

So, our standards specify tests and test limits, pass or fail.

Just looking for some additional guidance documents or standards that would 
help me convince the powers that be that such errors are unacceptable.

Well, according to the document, you need to take into account what you call 
“errors” as they are not errors but different measurements that need to be 
accounted for in determining the “pass-fail.”

At the end of the document are two references, which are much more detailed.

Rich


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Re: [PSES] standard for power suply for server room.

[Scott Aldous]

Disclaimer: I don't work on data center equipment.

Article 645 from the 2014 NEC includes the 600V rating limit in the
definition for Information Technology Equipment. The 2017 NEC no longer
includes the definition for ITE in Article 645, but 2017 NFPA 75 does and
it includes the 600V limit. In general the 600V limit comes from the
traditional US delineation between low voltage and medium voltage, however
the NEC is slowly moving toward a higher delineation point, at least for
some cases. For example the 2014 NEC changed Article 490 from covering
equipment over 600V nominal to equipment over 1000V nominal. The 2014 NEC
Handbook notes that there is a coordinated effort in this regard related to
alternative energy systems. Also see 250.180 (in general Part X of Article
250), where again starting in the 2014 NEC grounding requirements for
systems over 600V was changed to 1000V. The NEC is not clear on making a
distinction between ac/rms and dc voltages where these limits are imposed,
so the limit is generally applied regardless of waveform. In any case, this
is more of an installation issue than a product certification issue, though
for US certification it should be possible to install such equipment in
compliance with the NEC. It may be helpful to have a discussion on NEC
compliance with the customer to understand how they intend the NEC to be
applied to installations with their equipment.

With regard to certification, UL 60950-1 does include the limitation of
600V for information technology equipment, however the scope (of UL
60950-1) also indicates that the standard is also applicable to external
power supply units intended to supply other equipment within the scope of
this part of IEC 60905. Arguably, this leaves room for such an external
power supply's input not to fall under the 600V limit expressed in the
earlier part of the standard as long as the ITE it supplies falls under
that limit. In any case, Note 2 under clause 1.1.1 indicates that the
standard can be applied to electronic parts of equipment even if such
equipment doesn't wholly fall within the scope. I would think you could
apply UL 60950-1, and if there are any items that are not covered by the
requirements of the standard, you could supplement with requirements from
another standard, perhaps UL 508C
.

On Wed, Sep 21, 2016 at 8:02 AM, john Allen 
wrote:

> Bostjan
>
>
>
> I would seriously consider pointing out to your customer that their
> specified supply voltage is not a common one (at all) and ask them to state
> in more detail the system configuration which will provide it, and then you
> should know more clearly what you are up against and how to deal with it.
> Mention that the voltage does not appear to coincide with any
> generally-known commercial level known to be found in Europe or N.America,
> and thus ask where it will be found - suspicion might fall on some other
> country &/or an end-use customer that has some very special equipment, and
> might also point you towards some national standard(s) that could be
> national variations on known international ones.
>
>
>
> Ignorance is not a “crime” in cases like this where “something” is very
> unusual and where no-one here on this very experienced forum can provide
> any definitive, or even “educated”, guidance.
>
>
>
> John E Allen
>
> W.London, UK
>
>
>
> *From:* Boštjan Glavič [mailto:bostjan.gla...@siq.si]
> *Sent:* 21 September 2016 05:47
> *To:* EMC-PSTC@LISTSERV.IEEE.ORG
>
> *Subject:* Re: [PSES] standard for power suply for server room.
>
>
>
> Hi Ken,
>
>
>
> UL1012 has the same limitation as 60950-1.
>
>
>
> IEC 61010-1 is not OK since it is not a laboratory equipment or measuring
> equipment.
>
> IEC 62477-1 has also limitation in the scope however limits are 1000Vac
> and 1500VDC.
>
>
>
> Best regards,
>
> Bostjan
>
>
>
> *From:* IBM Ken [mailto:ibm...@gmail.com ]
> *Sent:* Wednesday, September 21, 2016 6:36 AM
> *To:* Boštjan Glavič 
> *Cc:* EMC-PSTC@LISTSERV.IEEE.ORG
> *Subject:* Re: [PSES] standard for power suply for server room.
>
>
>
> Hi Bostjan!
>
> You might be able to use 60950 or (UL1012?) anyway; I know the scope says
> "Mains or Battery powered up to 600V", but I think the focus of that limit
> (vs the 1000V limit in the LVD for example) might be on just Mains powered
> circuits, because 600V is the delineation point between "Low Voltage" and
> "high voltage" per the National Electrical Code.
>
>
>
> On the other hand, I believe the spacing calculations go higher than 600V
> in 60950 because internal voltages can go much higher than the supply
> voltage (boost stages in a SMPS, inverters for CCFL tubes, HV supply for
> corona wire in a laser printer, TV flyback, etc).
>
>
>
> Would 61010 work?
>
>
>
> -Ken A
>
>
>
> On Wed, Sep 21, 2016 at 12:09 AM, Boštjan Glavič 
> wrote:
>
> Dear experts I again need your opinion on below issue.
>
>
>
> Customer was asked for development of power supply which will be used

Re: [PSES] Measurement Accuracy

[Pawson, James]

Thanks for the link to that paper Rich, it makes for interesting reading in 
plain English.
James



From: Richard Nute [mailto:ri...@ieee.org]
Sent: 20 September 2016 21:18
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Measurement Accuracy

…

I didn’t know what “uncertainty” is, so I did a Google search and found this 
reference:

https://www.wmo.int/pages/prog/gcos/documents/gruanmanuals/UK_NPL/mgpg11.pdf


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[PSES] Wireless certification for large scale industrial equipment for professional use.

[Paul Smith]

I have questions on wireless in fixed Large scale stationary industrial 
equipment (permanent connected 3 phase, 150A / phase , 1000 Kgm  ). Can you 
help me with the following wireless questions?
1) Purchased wireless device:a)  Can the wireless device be designed 
permanently into the industrial equipment?
b) Or should the wireless device be shipped and installed aftermarket?
c)  Can you provide a modular approval?i)   Where is the modular 
approvals not accepted?ii) Where is local in-country residency 
required?iii)   Where is in-country testing required?(1)   Does testing include 
the wireless module only?(2)   Does testing also include the assemblies that 
utilize the wireless module?(3)   Does testing also include the whole 
industrial system as well?
Any information would be greatly appreciated.Regards  Paul J Smith
paul...@yahoo.com

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Re: [PSES] standard for power suply for server room.

[john Allen]

Bostjan

 

I would seriously consider pointing out to your customer that their specified 
supply voltage is not a common one (at all) and ask them to state in more 
detail the system configuration which will provide it, and then you should know 
more clearly what you are up against and how to deal with it. Mention that the 
voltage does not appear to coincide with any generally-known commercial level 
known to be found in Europe or N.America, and thus ask where it will be found - 
suspicion might fall on some other country &/or an end-use customer that has 
some very special equipment, and might also point you towards some national 
standard(s) that could be national variations on known international ones.

 

Ignorance is not a “crime” in cases like this where “something” is very unusual 
and where no-one here on this very experienced forum can provide any 
definitive, or even “educated”, guidance.

 

John E Allen

W.London, UK

 

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si] 
Sent: 21 September 2016 05:47
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] standard for power suply for server room.

 

Hi Ken,

 

UL1012 has the same limitation as 60950-1. 

 

IEC 61010-1 is not OK since it is not a laboratory equipment or measuring 
equipment.

IEC 62477-1 has also limitation in the scope however limits are 1000Vac and 
1500VDC.

 

Best regards,

Bostjan

 

From: IBM Ken [mailto:ibm...@gmail.com] 
Sent: Wednesday, September 21, 2016 6:36 AM
To: Boštjan Glavič 
Cc: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] standard for power suply for server room.

 

Hi Bostjan!

You might be able to use 60950 or (UL1012?) anyway; I know the scope says 
"Mains or Battery powered up to 600V", but I think the focus of that limit (vs 
the 1000V limit in the LVD for example) might be on just Mains powered 
circuits, because 600V is the delineation point between "Low Voltage" and "high 
voltage" per the National Electrical Code.  

 

On the other hand, I believe the spacing calculations go higher than 600V in 
60950 because internal voltages can go much higher than the supply voltage 
(boost stages in a SMPS, inverters for CCFL tubes, HV supply for corona wire in 
a laser printer, TV flyback, etc).

 

Would 61010 work?

 

-Ken A

 

On Wed, Sep 21, 2016 at 12:09 AM, Boštjan Glavič  wrote:

Dear experts I again need your opinion on below issue.

 

Customer was asked for development of power supply which will be used to supply 
a  server in data centre. Input to power supply is defined as 750VDC. 
Unfortunately no information is available how this DC supply voltage is 
generated and reference to PE. Most probably it will be floating.

 

Now the problem, what standard to use for such product?

 

-  Standard IEC 60950-1 which is most often used is limited to 600V 
rated voltage. Does it mean 600VRMS? Is it then allowed to approve also 
products with 600xsqrt(2)=848VDC  rated voltage according IEC 60950-1 or limit 
is also set to 600VDC? Where this limit actually comes from? If you check 
requirements for clearance and creepage distance they go quite higher than 600V.

-  Standard IEC 62477-1 could be appropriate standard however problem 
is that this standard is not worldwide harmonised and therefore no national 
certificates (US/CAN, China) are possible based on report according to this 
standard

-  What other standard would be OK for US/CAN?

 

I appreciate your feedback.

 

Best regards,

Bostjan

 

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Instructions: h

[PSES] Job opening - OSHA NRTL Program

[Kevin Robinson]

Hello All,

I wanted to share a position opening in OSHA's Nationally Recognized
Testing Laboratory (NRTL) Program as an engineer and laboratory assessor.

The position is located in Washington DC.

Additional details can be found at:
https://www.usajobs.gov/GetJob/ViewDetails/451085800

If you have any questions about what the position entails, please let me
know, however, DO NOT send resumes or salary inquiries to me as it can
disqualify you from consideration.

Kevin Robinson

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Re: [PSES] standard for power suply for server room.

[Boštjan Glavič]

Hi Zhang,

I do not know what technology they use for generating 750VDC. It could be some 
new technology.

They do not need to cover ITU or ETSI standards.

Best regards,
Bostjan

From: Zhangguoqing (A) [mailto:zhangguoq...@huawei.com]
Sent: Wednesday, September 21, 2016 11:24 AM
To: Boštjan Glavič ; EMC-PSTC@LISTSERV.IEEE.ORG
Subject: RE: standard for power suply for server room.

Hi Bostjan,

Why your Customer ask for 750Vdc input power supply? Normally for the DC input 
data centre equipments , the input is 400Vdc. Please find the standard ITU 
L.1200 and ITU L.1201, or ETSI 300 132-3-1, or  ATIS-0600315.01.2015.

Best Regards,
ZHANG Guoqing
Huawei Technologies Duesseldorf GmbH

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si]
Sent: 2016年9月21日 6:10
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] standard for power suply for server room.

Dear experts I again need your opinion on below issue.

Customer was asked for development of power supply which will be used to supply 
a  server in data centre. Input to power supply is defined as 750VDC. 
Unfortunately no information is available how this DC supply voltage is 
generated and reference to PE. Most probably it will be floating.

Now the problem, what standard to use for such product?


-  Standard IEC 60950-1 which is most often used is limited to 600V 
rated voltage. Does it mean 600VRMS? Is it then allowed to approve also 
products with 600xsqrt(2)=848VDC  rated voltage according IEC 60950-1 or limit 
is also set to 600VDC? Where this limit actually comes from? If you check 
requirements for clearance and creepage distance they go quite higher than 600V.

-  Standard IEC 62477-1 could be appropriate standard however problem 
is that this standard is not worldwide harmonised and therefore no national 
certificates (US/CAN, China) are possible based on report according to this 
standard

-  What other standard would be OK for US/CAN?

I appreciate your feedback.

Best regards,
Bostjan

-


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Re: [PSES] standard for power suply for server room.

[Zhangguoqing (A)]

Hi Bostjan,

Why your Customer ask for 750Vdc input power supply? Normally for the DC input 
data centre equipments , the input is 400Vdc. Please find the standard ITU 
L.1200 and ITU L.1201, or ETSI 300 132-3-1, or  ATIS-0600315.01.2015.
Best Regards,
ZHANG Guoqing
Huawei Technologies Duesseldorf GmbH

From: Boštjan Glavič [mailto:bostjan.gla...@siq.si]
Sent: 2016年9月21日 6:10
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] standard for power suply for server room.

Dear experts I again need your opinion on below issue.

Customer was asked for development of power supply which will be used to supply 
a  server in data centre. Input to power supply is defined as 750VDC. 
Unfortunately no information is available how this DC supply voltage is 
generated and reference to PE. Most probably it will be floating.

Now the problem, what standard to use for such product?


-  Standard IEC 60950-1 which is most often used is limited to 600V 
rated voltage. Does it mean 600VRMS? Is it then allowed to approve also 
products with 600xsqrt(2)=848VDC  rated voltage according IEC 60950-1 or limit 
is also set to 600VDC? Where this limit actually comes from? If you check 
requirements for clearance and creepage distance they go quite higher than 600V.

-  Standard IEC 62477-1 could be appropriate standard however problem 
is that this standard is not worldwide harmonised and therefore no national 
certificates (US/CAN, China) are possible based on report according to this 
standard

-  What other standard would be OK for US/CAN?

I appreciate your feedback.

Best regards,
Bostjan

-


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Re: [PSES] standard for power suply for server room.

[ce-test, qualified testing bv - Gert Gremmen]

If this is for European approval, one may simply use EN 60950 and make up a 
Technical construction
file listing the essential differences. A decent (now mandatory anyway) risk 
analysis would cover these differences, showing up as in individual risks. You 
may then choose to extrapolate 6950 values, or seek another standard covering 
high voltage aspects to cover for these risks. 
I think that this would be acceptable to any international body, as long as the 
risks remain well covered.

Regards,

Ing. Gert Gremmen
Approvals manager



+ ce marking of electrical/electronic equipment
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+ Compliance Testing and Design for CE marking
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From: Boštjan Glavič [mailto:bostjan.gla...@siq.si] 
Sent: Wednesday 21 September 2016 06:10
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] standard for power suply for server room.

Dear experts I again need your opinion on below issue.

Customer was asked for development of power supply which will be used to supply 
a  server in data centre. Input to power supply is defined as 750VDC. 
Unfortunately no information is available how this DC supply voltage is 
generated and reference to PE. Most probably it will be floating.

Now the problem, what standard to use for such product?

- Standard IEC 60950-1 which is most often used is limited to 600V rated 
voltage. Does it mean 600VRMS? Is it then allowed to approve also products with 
600xsqrt(2)=848VDC  rated voltage according IEC 60950-1 or limit is also set to 
600VDC? Where this limit actually comes from? If you check requirements for 
clearance and creepage distance they go quite higher than 600V.
- Standard IEC 62477-1 could be appropriate standard however problem is that 
this standard is not worldwide harmonised and therefore no national 
certificates (US/CAN, China) are possible based on report according to this 
standard
- What other standard would be OK for US/CAN?

I appreciate your feedback.

Best regards,
Bostjan

-

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David Heald  

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