Re: [PSES] Voltage Rating vs Voltage Specification

[Pete Perkins]

All,

 

   Yes, the consultant or safety engineers dream/nightmare.  We 
have to realize that the glass is half empty for most of the world and we have 
an ongoing opportunity to strike them across the knuckles with a ruler (as the 
nuns did in primary school) and begin the teaching mode.  

 

   As PT Barnum (the American circus entrepreneur) once said (and 
quoted often) ‘There is a fool born every minute’.  

 

   If the technical schools provided all of this detailed training 
we wouldn’t have anything to do.  

 

   So fill your peddler’s sack with all of these important stories 
and smile, but not laugh out loud, when you run into the same situation again 
(and again, and again).  

 

   Every project and every design team is an opportunity to 
straighten out the world.  

 

:>) 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: john Allen [mailto:john_e_al...@blueyonder.co.uk] 
Sent: Thursday, April 6, 2017 12:57 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Voltage Rating vs Voltage Specification

 

As Dave said, this is “age old problem” that we also faced at HP Bristol in the 
1980s when we built peripherals that had to operate across the World – and that 
meant from 100V 50 & 60Hz in Japan and up to 240V 50Hz for the UK and a few 
other places, AND +/- to cope with the relevant required local tolerances (and 
so effectively meant +/- 10% across the board). This meant careful selection 
and testing of PSUs and of the ratings to be marked on the end-use products, 
but fortunately most of our products did not have directly mains-powered 
motors. 

 

In practice, if you have a product that does have such motors then it may well 
mean that you need to produce separate models with different motors for the 
geographical areas that operate at the extremes of the voltage/frequency ranges 
– especially  those at the lower end thereof – or else change the designs to 
use DC motors supplied from full voltage/frequency range-capable PSUs (or, 
possibly, use AC motors rated for the lowest “worst case” voltage/ frequency / 
tolerance combination, but with solid state control systems which ensure that 
those motors are operated within that regime regardless of the actual supplied 
mains voltages/ frequencies/ tolerances?). 

 

OTOH, the latter approaches are probably impracticable in most cases for cost 
/space /weight / technology reasons , and so that  means you need a “horses for 
courses” approach.

 

John E Allen

W. London, UK

 

From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com] 
Sent: 06 April 2017 00:43
To: EMC-PSTC@LISTSERV.IEEE.ORG  
Subject: Re: [PSES] Voltage Rating vs Voltage Specification

 

Ha!  Age old problem.  Just have to explain it as you did.  And also for the 
end product consumer nameplate I don’t put the +-10% rating on the plate.  Had 
a major motor manufacturer recently trying to tell me that the motor they have 
rated for 230V was OK to run at 208V because it’s good for 230 +-10%. Had to 
explain to them that I need it to run at 208V – 10%.  Crickets on that one.

A previous motor from that manufacturer was rated for something like 208V @60Hz 
but 190V @50Hz and sure enough when tested at 208V + 10% @ 50Hz the windings 
saturated and drew crazy current.  

 

Likewise have to explain to design engineers that they cannot use a 230V motor 
in the product rated at 208V and rate the end product at 208V – 0%.

 

-Dave

 

From: Doug Powell [mailto:doug...@gmail.com] 
Sent: Wednesday, April 05, 2017 6:52 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG  
Subject: [PSES] Votlage Rating vs Voltage Specificaion

 

Hi all,

 

Has anyone found a good way to explain to non-compliance types the difference 
between voltage rating and voltage specification?  After all these years I 
still run into this discussion and have not found a good way to clear the air.

 

A classic example is an open frame AC/DC power supply used to produce the 
housekeeping voltages within a larger product.  In a recent example, the PSU 
datasheet stated the voltage input range as 85 to 264 VAC.  This is great and I 
really like that specification. However, I also had a design engineer who took 
those numbers from the datasheet and transcribed them directly to the rating 
label of his product.  As a result the agency engineer wanted to apply the ±10% 
rule to the rating label voltage and the rating tests were then 76.5 to 290.4 
VAC (this was not an ITE product).  Note: a little quick math shows that the 
264 VAC upper limit of the PSU is actually a result of 240 V plus 10%. 

 

All this seems obvious to me but apparently not to everyone ... and maybe it's 
me who is just a few sandwiches short of a picnic.

 

Re: [PSES] EU Certifications Required for Surge Protectors?

[Mick Maytum]

IEC SC 37A deals with surge protective devices, SPDs. Non-power SPDs 
(signal) are handled by SC 37A Working Group 4. WG 4 produced IEC 
61643-21 Low voltage surge protective devices – Part 21: Surge 
protective devices connected to
telecommunications and signalling networks – Performance requirements 
and testing methods. The corresponding CENELEC standard is EN 61643-21.
As I remember it these standards have just a series of tests at 
different levels with no real guidance of which ones to choose for 
certain applications such as POTS, antenna and Ethernet in your case.


The IEC/EN 61643-21 application Guide is IEC/EN 61643-22. These have 
Annex D (informative) Transmission characteristics related to IT 
systems, which covers Ethernet, DSL, POTS and cable TV (no antenna SPD 
transmission). Annex F (informative) Protection of Ethernet systems is 
more a tutorial than guidance.


Regards,
Mick Maytum


-- Original Message --
From: "Brian O'Connell" 
To: EMC-PSTC@listserv.ieee.org
Sent: 06/04/2017 22:00:35
Subject: Re: [PSES] EU Certifications Required for Surge PRotectors?

Dunno, as have just used the standards referenced in annex G of 
62368-1, or whatever component requirements that would be scoped per 
the various end-use equipment standards. Otherwise, perhaps materials 
and component and test requirements per EN62305-x or EN61643-x?


Brian


From: Scott Douglas [mailto:sdouglas...@gmail.com]
Sent: Thursday, April 06, 2017 1:30 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] EU Certifications Required for Surge PRotectors?

Hello All,

We have three products that we sell in USA. We are looking at getting 
these approved for sale in the EU. Our famous certification house says 
they do not create CB Reports for this kind of product. We are 
unfamiliar with any type of standards in the ROW for these products.


So, we are looking to find out what standards would apply, either 
EU-wide, or are there specific country requirements for these kinds of 
products?


Here is a brief explanation of the three products:

1.   POTS telephone surge protector.  The current model is a 
passive device with a pair of RJ-11 jacks for telephone in & out and a 
ground wire terminal.  Listed by UL to UL497A, Standard for Protectors 
for Communication Circuits.
2.   CATV/Antenna surge protector.  The current model is a passive 
device with a pair of F-connectors and a ground wire terminal. Listed 
by UL to UL497B, Standard for Protectors for Data Communications and 
Fire Alarm Circuits
3.   LAN / Ethernet surge protector.  The current model is a 
passive device with a pair of RJ-45 jacks for Ethernet (CAT5) in & out 
and a ground wire terminal.  Listed by UL to UL497B.

These are all passive devices, no power supply required.
We are in California and would appreciate any comments related to what 
EU standards would apply and what test houses might be a good choice to 
getting these approvals.

Your comments and advice will be well appreciated.
Thank you.
Scott

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Re: [PSES] Votlage Rating vs Voltage Specificaion

[Doug Powell]

  Unfortunately this was a consulting job and the arrangements had already been made by the company in question.  I was there to help them through the findings of the PDR. Doug   From: ri...@ieee.orgSent: April 6, 2017 11:46 AMTo: EMC-PSTC@LISTSERV.IEEE.ORGReply-to: ri...@ieee.orgSubject: Re: [PSES] Votlage Rating vs Voltage Specificaion   “As a result the agency engineer wanted to apply the ±10% rule to the rating label voltage…” Never submit a product to a certification house that you have not tested and evaluated for all the requirements.  You should not have any failures at the certification house (and the certification will be complete on the promise date).  Keep a running list of all your submittals and the deficiencies.  The list will be useful in your performance review or, if consulting, in building client confidence.  Easy to do with the CB report form (which you can submit with the product and will bias the cert house to your way of interpreting the requirements as applied to your product).   Rich 
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Re: [PSES] EU Certifications Required for Surge PRotectors?

[Brian O'Connell]

Dunno, as have just used the standards referenced in annex G of 62368-1, or 
whatever component requirements that would be scoped per the various end-use 
equipment standards. Otherwise, perhaps materials and component and test 
requirements per EN62305-x or EN61643-x?

Brian


From: Scott Douglas [mailto:sdouglas...@gmail.com] 
Sent: Thursday, April 06, 2017 1:30 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] EU Certifications Required for Surge PRotectors?

Hello All,

We have three products that we sell in USA. We are looking at getting these 
approved for sale in the EU. Our famous certification house says they do not 
create CB Reports for this kind of product. We are unfamiliar with any type of 
standards in the ROW for these products.

So, we are looking to find out what standards would apply, either EU-wide, or 
are there specific country requirements for these kinds of products?

Here is a brief explanation of the three products:

1.   POTS telephone surge protector.  The current model is a passive device 
with a pair of RJ-11 jacks for telephone in & out and a ground wire terminal.  
Listed by UL to UL497A, Standard for Protectors for Communication Circuits.
2.   CATV/Antenna surge protector.  The current model is a passive device 
with a pair of F-connectors and a ground wire terminal. Listed by UL to UL497B, 
Standard for Protectors for Data Communications and Fire Alarm Circuits
3.   LAN / Ethernet surge protector.  The current model is a passive device 
with a pair of RJ-45 jacks for Ethernet (CAT5) in & out and a ground wire 
terminal.  Listed by UL to UL497B.
These are all passive devices, no power supply required.
We are in California and would appreciate any comments related to what EU 
standards would apply and what test houses might be a good choice to getting 
these approvals.
Your comments and advice will be well appreciated.
Thank you.
Scott

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


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Re: [PSES] ESD Table Top Testing Bench with IEC 61000-4-2

[Ghery S. Pettit]

I remember dealing with a manager years ago who made layout decisions based
on esthetics.  I wouldn't want to deal with that situation again.  I would
tell your local Feng Shue expert to butt out and leave the lab equipment
(and the ESD tables are lab equipment) design to the EMC experts.  IEC
61000-4-2 is rather explicit about the design of the tables, and what your
Feng Shue person wants is not what the standard demands.  I know if I were
assessing your lab that would be an easy discrepancy to write.

 

Ghery S. Pettit, NCE

 

 

From: Harris, Kevin J (DSC) [mailto:kevinharr...@tycoint.com] 
Sent: Thursday, April 6, 2017 1:22 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] ESD Table Top Testing Bench with IEC 61000-4-2

 

Dear Colleagues,

 

We made a decision to renovate our laboratory with new lab benches. This has
led to a bit of a conundrum with our ESD benches. Our local Feng Shui expert
has proclaimed that it would not do to have all new lab benches except for
our old ESD wooden benches.  The issue we keep circling around is the new
benches would have steel legs with rubber feet under a non conducting table
top. IEC 61000-4-2 seemingly asks for a non conducting table in its
entirety. Does anyone know if such a setup deviation would make an iota of
difference to the test?

 

Thanks

 

Kevin

 

 

  _  


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Re: [PSES] ESD Table Top Testing Bench with IEC 61000-4-2

[John Woodgate]

It is very likely that the capacitance to the ground plane would be much higher
with the steel-legged table.
 
Are you really serious about feng shui?
 
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.
 
From: Harris, Kevin J (DSC) [mailto:kevinharr...@tycoint.com] 
Sent: Thursday, April 6, 2017 9:22 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] ESD Table Top Testing Bench with IEC 61000-4-2
 
Dear Colleagues,
 
We made a decision to renovate our laboratory with new lab benches. This has led
to a bit of a conundrum with our ESD benches. Our local Feng Shui expert has
proclaimed that it would not do to have all new lab benches except for our old
ESD wooden benches.  The issue we keep circling around is the new benches would
have steel legs with rubber feet under a non conducting table top. IEC 61000-4-2
seemingly asks for a non conducting table in its entirety. Does anyone know if
such a setup deviation would make an iota of difference to the test?
 
Thanks
 
Kevin
 
 
  _  


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[PSES] EU Certifications Required for Surge PRotectors?

[Scott Douglas]

Hello All,

We have three products that we sell in USA. We are looking at getting these
approved for sale in the EU. Our famous certification house says they do
not create CB Reports for this kind of product. We are unfamiliar with any
type of standards in the ROW for these products.

So, we are looking to find out what standards would apply, either EU-wide,
or are there specific country requirements for these kinds of products?

Here is a brief explanation of the three products:

1.   POTS telephone surge protector.  The current model is a passive
device with a pair of RJ-11 jacks for telephone in & out and a ground wire
terminal.  Listed by UL to UL497A, Standard for Protectors for
Communication Circuits.

2.   CATV/Antenna surge protector.  The current model is a passive
device with a pair of F-connectors and a ground wire terminal. Listed by UL
to UL497B, Standard for Protectors for Data Communications and Fire Alarm
Circuits

3.   LAN / Ethernet surge protector.  The current model is a passive
device with a pair of RJ-45 jacks for Ethernet (CAT5) in & out and a ground
wire terminal.  Listed by UL to UL497B.

These are all passive devices, no power supply required.

We are in California and would appreciate any comments related to what EU
standards would apply and what test houses might be a good choice to
getting these approvals.

Your comments and advice will be well appreciated.

Thank you.

Scott

-

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[PSES] ESD Table Top Testing Bench with IEC 61000-4-2

[Harris, Kevin J (DSC)]

Dear Colleagues,

We made a decision to renovate our laboratory with new lab benches. This has 
led to a bit of a conundrum with our ESD benches. Our local Feng Shui expert 
has proclaimed that it would not do to have all new lab benches except for our 
old ESD wooden benches.  The issue we keep circling around is the new benches 
would have steel legs with rubber feet under a non conducting table top. IEC 
61000-4-2 seemingly asks for a non conducting table in its entirety. Does 
anyone know if such a setup deviation would make an iota of difference to the 
test?

Thanks

Kevin




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Re: [PSES] Votlage Rating vs Voltage Specificaion

[Richard Nute]

 

“As a result the agency engineer wanted to apply the ±10% rule to the rating 
label voltage…”

 

Never submit a product to a certification house that you have not tested and 
evaluated for all the requirements.  You should not have any failures at the 
certification house (and the certification will be complete on the promise 
date).  Keep a running list of all your submittals and the deficiencies.  The 
list will be useful in your performance review or, if consulting, in building 
client confidence.  Easy to do with the CB report form (which you can submit 
with the product and will bias the cert house to your way of interpreting the 
requirements as applied to your product).  

 

Rich

 

 

 

 

 


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Re: [PSES] Votlage Rating vs Voltage Specificaion

[Richard Nute]

 

 

Hi Doug:

 

“…had a design engineer who took those numbers from the datasheet and 
transcribed them directly to the rating label of his product.”

 

This is the problem:  The safety guy didn’t do his job!  (I presume it wasn’t 
you!)

 

I prefer nominal input voltage rating numbers, not ranges.  The nominal number 
is used for the + and – 10% calculation.  The rating is not normally used by 
the customer unless he is moving the unit from one country to another.  Plug 
configuration sets the rating regardless of the label. So, the rating is mostly 
used by the certification house to maximize the safety performance of the unit. 
 

 

Extreme input voltages are likely to break the power supply, but unlikely to 
cause a safety deficiency.  

 

Best regards,

Rich

 

 


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Re: [PSES] Voltage Rating vs Voltage Specification

[john Allen]

As Dave said, this is “age old problem” that we also faced at HP Bristol in the 
1980s when we built peripherals that had to operate across the World – and that 
meant from 100V 50 & 60Hz in Japan and up to 240V 50Hz for the UK and a few 
other places, AND +/- to cope with the relevant required local tolerances (and 
so effectively meant +/- 10% across the board). This meant careful selection 
and testing of PSUs and of the ratings to be marked on the end-use products, 
but fortunately most of our products did not have directly mains-powered 
motors. 

 

In practice, if you have a product that does have such motors then it may well 
mean that you need to produce separate models with different motors for the 
geographical areas that operate at the extremes of the voltage/frequency ranges 
– especially  those at the lower end thereof – or else change the designs to 
use DC motors supplied from full voltage/frequency range-capable PSUs (or, 
possibly, use AC motors rated for the lowest “worst case” voltage/ frequency / 
tolerance combination, but with solid state control systems which ensure that 
those motors are operated within that regime regardless of the actual supplied 
mains voltages/ frequencies/ tolerances?). 

 

OTOH, the latter approaches are probably impracticable in most cases for cost 
/space /weight / technology reasons , and so that  means you need a “horses for 
courses” approach.

 

John E Allen

W. London, UK

 

From: Nyffenegger, Dave [mailto:dave.nyffeneg...@bhemail.com] 
Sent: 06 April 2017 00:43
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: Re: [PSES] Voltage Rating vs Voltage Specification

 

Ha!  Age old problem.  Just have to explain it as you did.  And also for the 
end product consumer nameplate I don’t put the +-10% rating on the plate.  Had 
a major motor manufacturer recently trying to tell me that the motor they have 
rated for 230V was OK to run at 208V because it’s good for 230 +-10%. Had to 
explain to them that I need it to run at 208V – 10%.  Crickets on that one.

A previous motor from that manufacturer was rated for something like 208V @60Hz 
but 190V @50Hz and sure enough when tested at 208V + 10% @ 50Hz the windings 
saturated and drew crazy current.  

 

Likewise have to explain to design engineers that they cannot use a 230V motor 
in the product rated at 208V and rate the end product at 208V – 0%.

 

-Dave

 

From: Doug Powell [mailto:doug...@gmail.com] 
Sent: Wednesday, April 05, 2017 6:52 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Votlage Rating vs Voltage Specificaion

 

Hi all,

 

Has anyone found a good way to explain to non-compliance types the difference 
between voltage rating and voltage specification?  After all these years I 
still run into this discussion and have not found a good way to clear the air.

 

A classic example is an open frame AC/DC power supply used to produce the 
housekeeping voltages within a larger product.  In a recent example, the PSU 
datasheet stated the voltage input range as 85 to 264 VAC.  This is great and I 
really like that specification. However, I also had a design engineer who took 
those numbers from the datasheet and transcribed them directly to the rating 
label of his product.  As a result the agency engineer wanted to apply the ±10% 
rule to the rating label voltage and the rating tests were then 76.5 to 290.4 
VAC (this was not an ITE product).  Note: a little quick math shows that the 
264 VAC upper limit of the PSU is actually a result of 240 V plus 10%. 

 

All this seems obvious to me but apparently not to everyone ... and maybe it's 
me who is just a few sandwiches short of a picnic.

 

I would be grateful to hear any experiences where explanations were successful 
and lasting.

 

 

-- 

 

Douglas E Powell

doug...@gmail.com
http://www.linkedin.com/in/dougp01

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This message is from the IEEE Product Safety Engineering Society emc-pstc 
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Re: [PSES] Votlage Rating vs Voltage Specificaion

[John Woodgate]

There is a vocabulary issue here. The IEC defines 'rated' as [simplified] 'the 
value stated by the manufacturer'. So for the PSU manufacturer, 85 V and 264 V 
are indeed 'rated' values. But of course you are right; the product should have 
rated values of [probably] 100 V to 240 V. It's got to be part of the training 
of the design engineer.
 
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.
 
From: Doug Powell [mailto:doug...@gmail.com] 
Sent: Wednesday, April 5, 2017 11:52 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: [PSES] Votlage Rating vs Voltage Specificaion
 
Hi all,
 
Has anyone found a good way to explain to non-compliance types the difference 
between voltage rating and voltage specification?  After all these years I 
still run into this discussion and have not found a good way to clear the air.
 
A classic example is an open frame AC/DC power supply used to produce the 
housekeeping voltages within a larger product.  In a recent example, the PSU 
datasheet stated the voltage input range as 85 to 264 VAC.  This is great and I 
really like that specification. However, I also had a design engineer who took 
those numbers from the datasheet and transcribed them directly to the rating 
label of his product.  As a result the agency engineer wanted to apply the ±10% 
rule to the rating label voltage and the rating tests were then 76.5 to 290.4 
VAC (this was not an ITE product).  Note: a little quick math shows that the 
264 VAC upper limit of the PSU is actually a result of 240 V plus 10%. 
 
All this seems obvious to me but apparently not to everyone ... and maybe it's 
me who is just a few sandwiches short of a picnic.
 
I would be grateful to hear any experiences where explanations were successful 
and lasting.
 
 
-- 
 
Douglas E Powell

doug...@gmail.com  
http://www.linkedin.com/in/dougp01
-

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 
 >
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Attachments are not permitted but the IEEE PSES Online Communities site at 
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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:
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Mike Cantwell  > 
For policy questions, send mail to:
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List rules: http://www.ieee-pses.org/listrules.html

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