Re: DC circuits

[Rich Nute]

Hi Chris:


>   In other words: don't test if you know already the result before the test 
> is made.

A good safety engineer can predict the result 
(not pass-fail but the measured value) of each 
and every safety test.  

For example, a good safety engineer can predict 
leakage current to within 0.25 mA, and hi-pot 
breakdown to the nearest 1 kV.

Despite the ability to predict test results,
tests (and the records thereto) are necessary for 
proof of compliance.

If the results of any test are different than
predicted, then a good safety engineer will 
determine why the test results are not what he
predicted.

Having said this, there are some tests that are 
not necessary, such as the simulation of failure
of basic insulation.

Short-circuiting of operational insulation may 
not be easy to predict in some instances.

However, for SELV and many other secondary
circuits, one can rationalize no testing of
operational insulation (per the IEC 60950 
requirements for operational insulation, 
sub-clause 5.4.4).  Note that all of these 
requirements are connected together by "or"; 
this means that the product need only comply 
with one of the requirements.

1.  Stipulate that the circuit does not meet the
creepage or clearance requirements.

2.  Stipulate no hi-pot tests.

3a. If the operational insulation is on a PWB
rated V-1 or better, then no tests.

3b. If the consequence of short-circuiting an
operational insulation is not thermally
related to a safety insulation (B, S, or R), 
then no test.

3a and 3b will be true in most instances.  Hence,
no test.  We commonly invoke 3a for our low-
voltage secondary circuits.


Best regards,
Rich


ps:  Note that Japan and Korea do no accept 60 V
 dc as SELV; their limit is 42 V dc.  However,
 the operational insulation requirements are
 applicable to all circuits, not just SELV. 







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RE: Australia Safety

[Kevin Richardson]

Hi Richard,

I am afraid I led you astray a little for NZ.  This type of power supply
does NOT require any form of approval presently in NZ.

A little history
These types of devices have not been required to be approved in NZ in the
past.  NZ is presently completely revamping their electrical regulations etc
and were supposed to have a completely new list by now of those products
which are required to gain approval etc.  As part of this revamp, NZ was
supposed to have modified the legislation and regulations to facilitate them
being able to change which products were "Declared Articles" very quickly
instead of the more cumbersome and lengthy process required now.  The new
regulations etc were also supposed to introduce a category of approval which
required only that the manufacturer/supplier sign and hold a Declaration of
Conformity.  The new regulations/list of Declared Articles is not yet
published (first cut is due around Dec 00).

I understood that stand-alone power supplies were to be included on the new
list of product requiring approval.  First of all the new list is not yet
produced and secondly I have now confirmed these type of devices will not be
included, even in the second more thorough list scheduled for Feb 2001.

It is possible these devices MAY be included in the product type listing
which requires a DoC to be held on file etc but can not positively confirm
this at this time.

My apology for misleading you.

Best regards,
Kevin Richardson

Stanimore Pty Limited
Compliance Advice & Solutions for Technology Products and Services
(Legislation/Regulations/Standards)
Ph:   02-4329-4070   (Int'l: +61-2-4329-4070)
Fax:  02-4328-5639   (Int'l: +61-2-4328-5639)
Mobile:  04-1224-1620   (Int'l: +61-4-1224-1620)
Email:k...@compuserve.com
 kevin.richard...@ieee.org
 k...@technologist.com (alternate internet)


-Original Message-
From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf
Of wo...@sensormatic.com
Sent: Tuesday, 10 October 2000 11:02 PM
To: emc-p...@majordomo.ieee.org
Subject: Australia Safety




Is safety certification mandatory in Australia or New Zealand for external
power supply "adapters" such as the types used with laptop computers? If so,
what is the mandatory safety standard and which agency certifications are
accepted?

Richard Woods

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RE: Neutral/Earth connections

[rbusche]

Another possibility is that the US equipment may have been designed for a
three phase "Y"  input with a neutral and was used on a European three phase
"delta" circuit. Someone could have then tied the neutral terminal to ground
creating a serious hazard as well as a voltage imbalance.

Just a thought...

Rick
 -Original Message-
From:   Rich Nute [mailto:ri...@sdd.hp.com] 
Sent:   Wednesday, October 11, 2000 3:38 PM
To: wo...@sensormatic.com; k3...@eurobell.co.uk
Cc: emc-p...@majordomo.ieee.org
Subject:Re: Neutral/Earth connections





Hi Richard and Dave:


In answer to Richard's comment:

>   The neutral is never to be tied to the chassis of equipment. It is not
>   allowed by any safety standard nor the National Electrical Code. The
neutral
>   is to be tied to earth at one and only one point and that is that the
>   service entrance or the electrical box fed by an on-premises
transformer. I
>   would have to seriously question if this product was designed to any
>   recognized safety standard. Even if it does not pop the breaker, is it
safe?

See IEC 60950, Sub-clause 1.2.12, Power Distribution,
and Sub-clause 1.2.12.1, TN-C system and Figure 3.

This reference describes a scheme by which accessible 
conductive parts are grounded via the neutral 
conductor of the power distribution system.

Also, see NEC 250-60, Frames of Ranges and Clothes
Dryers, and 250-61, Use of Grounded Circuit Conductor
for Grounding Equipment, and 250-61(b), Load Side
Equipment, Exceptions.  

In the USA, the frames of cooking ranges, wall-mounted
ovens, counter-mounted cooking units, and clothes 
dryers may be grounded via the neutral conductor (i.e.,
the TN-C scheme).

However, the TN-C grounding scheme is not permitted for 
the equipment mentioned in the original posting. 


In answer to Dave's question:

While there is no general rule regarding configuration
of exported equipment, there are specific rules for
some kinds of equipment (laser, x-ray, medical, etc.) 
that requires that the equipment must meet either USA 
safety standards or the safety standards of the 
destination country.

Personally, I find it hard to believe that a reputable
USA manufacturer would supply equipment where the 
neutral was connected to the chassis.  So, I wonder if
there is some sort of mix-up due to wiring the unit for
the U.K.?  

A USA 240-V unit is provided with three wires:

+120 V  (typically black)
-120 V  (typically red)
Ground/Chassis/PE   (green or green/yellow)

A USA 120-0-120 V unit is provided with four wires:

   +120 V   (typically black)
0  (neutral)(white or natural grey)
   -120 V   (typically red)
   Ground/Chassis/PE(green or green/yellow)

So, I wonder if the unit was a 240-V unit, but the
wires were identified as +120, -120, and 0/chassis?  
Then, I wonder if the use of a 120/120 marking implied 
a neutral?  I suspect that there is some confusion
because Dave describes connecting the unit to a U.K.
120-0-120 source.  I would expect that the unit could
be connected to a U.K. 240 V source (phase and neutral)
with the third wire connected to PE.

I suggest a further study of the unit or its schematic
to determine if the chassis is used as a current-
carrying conductor (i.e., neutral).


Best regards,
Rich






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RE: Neutral/Earth connections

[O'Shaughnessy, Paul]

He's right.  Tying neutral directly to the chassis is just WRONG, even if
you could be sure it would always be neutral (not guaranteed at all).
Sounds like somebody got neutral and the safety ground mixed up.  I'd send
the unit back to the manufacturer with a nasty note.  I would also question
(if they have regulatory marks) whether anyone qualified to judge safety
ever looked at it.

-Original Message-
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com]
Sent: Wednesday, October 11, 2000 3:31 PM
To: emc-p...@majordomo.ieee.org
Subject: RE: Neutral/Earth connections



The neutral is never to be tied to the chassis of equipment. It is not
allowed by any safety standard nor the National Electrical Code. The neutral
is to be tied to earth at one and only one point and that is that the
service entrance or the electrical box fed by an on-premises transformer. I
would have to seriously question if this product was designed to any
recognized safety standard. Even if it does not pop the breaker, is it safe?

Richard Woods

--
From:  k3row [SMTP:k3...@eurobell.co.uk]
Sent:  Wednesday, October 11, 2000 2:27 PM
To:  emc-p...@majordomo.ieee.org
Subject:  Neutral/Earth connections


The company that I work for in the U.K has recentlyreceived from the
USA an
item of test equipment, provided to us under contract, in which, we
discovered, the 240v neutral line was connected to earth/unit
chassis. This
became apparent when the unit was plugged into a U.K 120-0-120
supply and
protective devices tripped..

My questions are these:

I am not familiar with US safety standards. Am I correct in assuming
that,
for instance, the National Electrical Code and standards such as UL
1950
would only allow such a neutral/earth connection within the
equipment if
the power source is derived from, say, an isolation transformer? Or
is
there no U.S standardisation with regard to this.

Given that we were not informed in advance of any such constraint on
the
manner in which power was to be supplied to the equipment, I wonder
how
widespread the issue of supply of such equipment to the U.K might
be. Any
comments anyone?

What would be the view of people in the USA with respect of the
supply of
such an item of equipment to the U.K. Do US Standards, Codes of
Practice
etc dictate that supplied equipment must be safe when used in the
receiving
country, as opposed to the supplying country?

 Thanks for reading this. I look forward to any comments

Dave Palmer



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RE: Neutral/Earth connections

[Crane, Lauren]

Dave, 

It is my understanding, as you state, that earth ground and neutral should
not be tied together in a piece of equipment except to ground reference the
output of a transformer that is part of the equipment, although I can not
quote chapter and verse from the NEC or 1950 on this. I suspect there are
exceptions depending on what type of electrical distribution system the
equipment is intended for. 

Regardless of what may exist in the 'States for "codes of practice", I think
both the Machinery Directive and the Low Voltage Directive of the European
Union would require the IMPORTER OF RECORD for the device to assure safety
in the intended use location. 

Without more info it is hard to speculate, but that won't stop me...

If this is test equipment your company bought directly from a US company,
and not through some other European distributor, then even though the
manufacturer might want to know better to foster good business relations
with your company, the final compliance responsibility may lie with your
company. 

Since you say it was provided under contract, you probably are the importer
of record, and it is likely you have a classic customer-supplier
miscommunication with regard to CE compliance and the understanding of the
manufacturer about your supply system.  

Lauren Crane
*   Product Safety & Compliance Engineer
*   Ion Beam and Thermal Processing Systems
*   Axcelis Technologies Inc. 
*   108 Cherry Hill Dr. 
*   Beverly, MA  01915
*   978.921-9745   lauren.cr...@axcelis.com


-Original Message-
From: k3row [mailto:k3...@eurobell.co.uk]
Sent: Wednesday, October 11, 2000 2:27 PM
To: emc-p...@majordomo.ieee.org
Subject: Neutral/Earth connections



The company that I work for in the U.K has recentlyreceived from the USA an
item of test equipment, provided to us under contract, in which, we
discovered, the 240v neutral line was connected to earth/unit chassis. This
became apparent when the unit was plugged into a U.K 120-0-120 supply and
protective devices tripped..

My questions are these:

I am not familiar with US safety standards. Am I correct in assuming that,
for instance, the National Electrical Code and standards such as UL 1950
would only allow such a neutral/earth connection within the equipment if
the power source is derived from, say, an isolation transformer? Or is
there no U.S standardisation with regard to this.

Given that we were not informed in advance of any such constraint on the
manner in which power was to be supplied to the equipment, I wonder how
widespread the issue of supply of such equipment to the U.K might be. Any
comments anyone?

What would be the view of people in the USA with respect of the supply of
such an item of equipment to the U.K. Do US Standards, Codes of Practice
etc dictate that supplied equipment must be safe when used in the receiving
country, as opposed to the supplying country?

 Thanks for reading this. I look forward to any comments

Dave Palmer



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Re: Neutral/Earth connections

[Rich Nute]

Hi Richard and Dave:


In answer to Richard's comment:

>   The neutral is never to be tied to the chassis of equipment. It is not
>   allowed by any safety standard nor the National Electrical Code. The neutral
>   is to be tied to earth at one and only one point and that is that the
>   service entrance or the electrical box fed by an on-premises transformer. I
>   would have to seriously question if this product was designed to any
>   recognized safety standard. Even if it does not pop the breaker, is it safe?

See IEC 60950, Sub-clause 1.2.12, Power Distribution,
and Sub-clause 1.2.12.1, TN-C system and Figure 3.

This reference describes a scheme by which accessible 
conductive parts are grounded via the neutral 
conductor of the power distribution system.

Also, see NEC 250-60, Frames of Ranges and Clothes
Dryers, and 250-61, Use of Grounded Circuit Conductor
for Grounding Equipment, and 250-61(b), Load Side
Equipment, Exceptions.  

In the USA, the frames of cooking ranges, wall-mounted
ovens, counter-mounted cooking units, and clothes 
dryers may be grounded via the neutral conductor (i.e.,
the TN-C scheme).

However, the TN-C grounding scheme is not permitted for 
the equipment mentioned in the original posting. 


In answer to Dave's question:

While there is no general rule regarding configuration
of exported equipment, there are specific rules for
some kinds of equipment (laser, x-ray, medical, etc.) 
that requires that the equipment must meet either USA 
safety standards or the safety standards of the 
destination country.

Personally, I find it hard to believe that a reputable
USA manufacturer would supply equipment where the 
neutral was connected to the chassis.  So, I wonder if
there is some sort of mix-up due to wiring the unit for
the U.K.?  

A USA 240-V unit is provided with three wires:

+120 V  (typically black)
-120 V  (typically red)
Ground/Chassis/PE   (green or green/yellow)

A USA 120-0-120 V unit is provided with four wires:

   +120 V   (typically black)
0  (neutral)(white or natural grey)
   -120 V   (typically red)
   Ground/Chassis/PE(green or green/yellow)

So, I wonder if the unit was a 240-V unit, but the
wires were identified as +120, -120, and 0/chassis?  
Then, I wonder if the use of a 120/120 marking implied 
a neutral?  I suspect that there is some confusion
because Dave describes connecting the unit to a U.K.
120-0-120 source.  I would expect that the unit could
be connected to a U.K. 240 V source (phase and neutral)
with the third wire connected to PE.

I suggest a further study of the unit or its schematic
to determine if the chassis is used as a current-
carrying conductor (i.e., neutral).


Best regards,
Rich






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Re: DC circuits

[Chris Collin]

Scott,

Operational insulation has tree options (I quote EN60950/A4, Subclause 5.4.4):
- creepage and clearance distances as in TABLE 5
- electric strength test as in TABLE 18 part1: 500V dc.
- both circuits are short-circuited with the following results:
-> no overheating of materials creating a fire unless the material is V-1
-> thermal damage to BI, SI or RI, creating a risk of electric shock.

In some (many cases), the 3rd option is the most feasible.
Also keep in mind Subclause 1.4.1: "If it is evident from the design 
...that a certain test is not applicable, the test shall not be made".
Ïn other words: don't test if you know already the result before the test is 
made.

Regards,
Chris


On Wed, 11 October 2000, Scott Lemon wrote:

> Sender: owner-emc-p...@ieee.org
> X-Listname: emc-pstc
> To: "Emc-Pstc Bulletin Board (E-mail)" 
> Delivered-To: altavista.com%globalass...@altavista.com
> X-Moderator-Address: emc-pstc-appro...@majordomo.ieee.org
> X-Resent-To: Multiple Recipients 
> Received: by ruebert.ieee.org (8.9.3/8.9.3)id NAA01395; Wed, 11 Oct 2000 
> 13:12:16 -0400 (EDT)
> from ruebert.ieee.org (199.172.136.3)
>   by smtp.c012.sfo.cp.net (209.228.13.145) with SMTP; 11 Oct 2000 
> 11:55:02 -0700
>   by ruebert.ieee.org (8.9.3/8.9.3)   id NAA01395; Wed, 11 Oct 2000 
> 13:12:16 -0400 (EDT)
> Content-Length: 1538
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> charset="iso-8859-1"
> X-Received: 11 Oct 2000 18:55:02 GMT
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> Subject: DC circuits  X-Info: [Un]Subscribe requests to
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>   majord...@majordomo.ieee.org
> From: Scott Lemon 
> Return-Path: 
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> Date: Wed, 11 Oct 2000 10:17:00 -0700
> X-Mailer: Internet Mail Service (5.5.2650.21)
> Message-Id: <2ff612b13481d311b40a009027b0c838bc8...@mail.packetcom.com>
> 
> 
> Hello Group,
> 
> I have a good idea (first hand knowledge) of what UL looks for with respect
> to dc supply circuitry  (with caveats on the supply) that it is SELV secondary with operational
> insulation requiring 500 Vac/707 Vdc dielectric withstand performance to
> ground/other secondary circuits.  
> 
> Can anyone identify how other agencies/test houses (using 950 based
> standards, like within the EU) are classifying SELV level telecom dc supply
> circuits, particularly with respect to the dielectric withstand
> performance??  
> 
> Is 1000 Vac/1414 Vdc used or 500 Vac/707 Vdc?  What is the rationale either
> way?  
> 
> In lieu of the dielectric testing, how are the other options for operational
> insulation in IEC/EN 60950 (clause 5.4.4) viewed (generally acceptable)??
> 
> I have heard varying opinions on the above and would like to collect even
> more!
> 
> Thanks in advance!
> 
> Best Regards,
> 
> Scott Lemon
> Caspian Networks - RTP
> email: sle...@caspiannetworks.com
> phone:  (919) 466-0315
> fax: tbd
> 
> 
> ---
> This message is from the IEEE EMC Society Product Safety
> Technical Committee emc-pstc discussion list.
> 
> To cancel your subscription, send mail to:
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> with the single line:
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RE: Label Rub test per IEC60950

[Massey, Doug C.]

THANKS TO ALL FOR THE REPLIES - THANKS, NED, FOR THE EXACT ANSWER !!

-Original Message-
From: Ned Devine [mailto:ndev...@entela.com]
Sent: Tuesday, October 10, 2000 10:01 AM
To: emc-p...@majordomo.ieee.org
Subject: RE: Label Rub test per IEC60950



Hi,

The requirement is for "The petroleum spirit to be used for the test is
aliphatic solvent hexane having a maximum aromatics content of 0,1 % by
volume, a kauri-butenol value of 29, an initial boiling point of
approximately 65 °C, a dry point of approximately 69 °C and a mass per unit
volume of approximately 0,7 kg/l."

Our Chemist researched it and found it is Hexane, 95+%.  The Aldrich Cat.
No. is 20,875-2.  The CAS number is 110-5A-3.

The Isopropyl Alcohol is 100% (not rubbing alcohol) and is a very aggressive
solvent.  It is at least as harsh as the Hexane.

Ned Devine
Entela, Inc.
Program Manager III
Phone 616 248 9671
Fax  616 574 9752
e-mail  ndev...@entela.com 



-Original Message-
From: Robert Johnson [mailto:robe...@ma.ultranet.com]
Sent: Sunday, October 08, 2000 11:20 PM
To: E Eszlari
Cc: emc-p...@majordomo.ieee.org
Subject: Re: Label Rub test per IEC60950



As I recall, the chemical that was described is what is sold in the US as
kerosene. It appeared way back in the early UL standards that way.
Since this is a petroleum distillate characterized mainly by its molecular
weight and what temperature it comes off the refining process, describing it
is
kind of like coming up with a chemical formula for milk. Too messy to try.
The
term kerosene was not sufficient to properly describe it worldwide, so this
description was what was recommended by those in the business.
Many have also used cigarette lighter fluid for the test. Functionally it is
pretty equivalent, just a lighter distillate. The container's much more
convenient.

Bob

E Eszlari wrote:

> Hi Doug,
>
> I think you will find that the common mineral spirit found in your local
> hardware store is used by most companies to perform the test in order to
get
> a good idea if the label and print will pass. I have found that UL will
> accept the results. By the way, the gallon of mineral spirits I have at
home
> is also labeled "petroleum spirit". If you are doubtful of this test
result,
> you may want to have an agency such as UL do the test for you or use an
> approved label system.
>
> In my experience I have found mineral spirit to be a more harsh chemical
> than Isopropyl Alcohol. The alcohol test is performed on labels that are
> used in medical environments per IEC 60601.
>
> Ed
>
> >From: "Massey, Doug C." 
> >Reply-To: "Massey, Doug C." 
> >To: "'IEEE Forum'" 
> >Subject: Label Rub test per IEC60950
> >Date: Fri, 6 Oct 2000 10:22:27 -0400
> >
> >
> >Does anyone know what the trade name for the chemical used for the rub
test
> >in 60950 clause 1.7.15 is ?
> >The standard calls it "petroleum spirit", then describes an aliphatic
> >solvent hexane, with several properties, none of which are a chemical
> >formula.
> >
> >Is it common mineral spirits available at most hardware stores?
> >
> >Also, is Isopropyl Alcohol a more harsh solvent than the petroleum
spirits?
> >
> >Thanks
> >
> >Doug Massey
> >Safety Approvals Engineer
> >LXE, Inc.
> >Norcross, GA., USA
> >Ph.  (770) 447-4224 x3607
> >FAX (770) 447-6928
> >e-mail: masse...@lxe.com
> >
> >Cruise our website at: http:\\www.lxe.com
> >
> >
> >
> >---
> >This message is from the IEEE EMC Society Product Safety
> >Technical Committee emc-pstc discussion list.
> >
> >To cancel your subscription, send mail to:
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> >
> >For help, send mail to the list administrators:
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> >
> >For policy questions, send mail to:
> >  Richard Nute:   ri...@ieee.org
> >
> >
>
> _
> Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.
>
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> ---
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RE: Neutral/Earth connections

[WOODS]

The neutral is never to be tied to the chassis of equipment. It is not
allowed by any safety standard nor the National Electrical Code. The neutral
is to be tied to earth at one and only one point and that is that the
service entrance or the electrical box fed by an on-premises transformer. I
would have to seriously question if this product was designed to any
recognized safety standard. Even if it does not pop the breaker, is it safe?

Richard Woods

--
From:  k3row [SMTP:k3...@eurobell.co.uk]
Sent:  Wednesday, October 11, 2000 2:27 PM
To:  emc-p...@majordomo.ieee.org
Subject:  Neutral/Earth connections


The company that I work for in the U.K has recentlyreceived from the
USA an
item of test equipment, provided to us under contract, in which, we
discovered, the 240v neutral line was connected to earth/unit
chassis. This
became apparent when the unit was plugged into a U.K 120-0-120
supply and
protective devices tripped..

My questions are these:

I am not familiar with US safety standards. Am I correct in assuming
that,
for instance, the National Electrical Code and standards such as UL
1950
would only allow such a neutral/earth connection within the
equipment if
the power source is derived from, say, an isolation transformer? Or
is
there no U.S standardisation with regard to this.

Given that we were not informed in advance of any such constraint on
the
manner in which power was to be supplied to the equipment, I wonder
how
widespread the issue of supply of such equipment to the U.K might
be. Any
comments anyone?

What would be the view of people in the USA with respect of the
supply of
such an item of equipment to the U.K. Do US Standards, Codes of
Practice
etc dictate that supplied equipment must be safe when used in the
receiving
country, as opposed to the supplying country?

 Thanks for reading this. I look forward to any comments

Dave Palmer



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RE: PCB temp ratings, etc...

[WOODS]

Let me see if I understand. The board without the resist coating has a UL
certified temperature rating. We don't know the temperature rating of the
coating; but if it does ignite, at least we know the certified burn rate.
Well, perhaps the ignition temperature is high enough so that we don't have
to be concerned with ignition, but only the esthetics of discoloration.
There does appear to be a gap in the certification process.

Richard Woods

--
From:  Peter Tarver [SMTP:ptar...@nortelnetworks.com]
Sent:  Wednesday, October 11, 2000 2:16 PM
To:  emc-p...@ieee.org
Subject:  RE: PCB temp ratings, etc...

Richard - 

Then the answer is no.  The MOT, as Pete Perkins pointed out,
establishes the test points for thermal conditioning, but solder resists are
then tested in conjunction with the PWB only for flammability
classification.

Regards, 

Peter L. Tarver, PE 
ptar...@nortelnetworks.com 


-Original Message- 
From: wo...@sensormatic.com [ mailto:wo...@sensormatic.com
 ] 
Sent: Wednesday, October 11, 2000 6:11 PM 


You are correct. I used the wrong term. I should have said the
solder resist 
coating. Is this coating included in the temperature ratings? 

Richard Woods 

-- 
From:  mike harris [SMTP:tecco...@i-cafe.net] 
Sent:  Wednesday, October 11, 2000 11:25 AM 

Hi Richard & Peter, 
 
Richard, I wonder if  you are calling the solder resist
coating as conformal coating? 
 
Mike Harris/Teccom 


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RE: DoC & TCF

[Bailey, Jeff]

Ooops I meant to say "I can't guarantee you that" NOT "I won't provide you
with" 

Maybe I should stop using my cell phone so much...  :-)

Jeff

-Original Message-
From: Bailey, Jeff [mailto:jbai...@mysst.com]
Sent: Wednesday, October 11, 2000 12:35 PM
To: 'emc-pstc'
Subject: RE: DoC & TCF



Hi Richard,

AB uses the TCF route quite frequently and they list their DoC's online.
Try going to http://www.ab.com/certification/ce/docs/index.html and look at
a couple of DoC's through
the links found there.  It won't provide you with the rules for wording are
adhered to
or not but it may give you a start.


Jeff Bailey 
Compliance Engineering 
SST - A Division of Woodhead Canada 
Phone: (519) 725 5136 ext. 363 
Fax: (519) 725 1515 
Email: jbai...@sstech.on.ca 
Web: www.sstech.on.ca 


All comments contained in the message are my own and do not necessarily
express the views of SST/Woodhead Canada Limited. 


-Original Message-
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com]
Sent: Wednesday, October 11, 2000 8:25 AM
To: emc-p...@majordomo.ieee.org
Subject: DoC & TCF



I have seen several Declarations of Compliance when harmonized standards are
used, but I don't recall seeing one where the TCF route was followed for one
or more essential requirements. What wording is used on DoC to note that a
Competent/Notified Body rendered an opinion that a product complies to some
particular essential requirement by using a non-harmonized standard?
 
Richard Woods

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 Richard Nute:   ri...@ieee.org

Neutral/Earth connections

[k3row]

The company that I work for in the U.K has recentlyreceived from the USA an
item of test equipment, provided to us under contract, in which, we
discovered, the 240v neutral line was connected to earth/unit chassis. This
became apparent when the unit was plugged into a U.K 120-0-120 supply and
protective devices tripped..

My questions are these:

I am not familiar with US safety standards. Am I correct in assuming that,
for instance, the National Electrical Code and standards such as UL 1950
would only allow such a neutral/earth connection within the equipment if
the power source is derived from, say, an isolation transformer? Or is
there no U.S standardisation with regard to this.

Given that we were not informed in advance of any such constraint on the
manner in which power was to be supplied to the equipment, I wonder how
widespread the issue of supply of such equipment to the U.K might be. Any
comments anyone?

What would be the view of people in the USA with respect of the supply of
such an item of equipment to the U.K. Do US Standards, Codes of Practice
etc dictate that supplied equipment must be safe when used in the receiving
country, as opposed to the supplying country?

 Thanks for reading this. I look forward to any comments

Dave Palmer



---
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 unsubscribe emc-pstc

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 Richard Nute:   ri...@ieee.org

RE: Standards hierarchy

[Maxwell, Chris]

In the instance of EN 61000-3-2 and EN 61000-3-3, we MUST look to regulatory
authorities to make the decision.  

I think the basis of the whole argument is this:

For many products covered by these standards, the "essential requirements"
as listed by many competent EMC engineers would not include EN 61000-3-2 and
EN 61000-3-3.  In their eyes it only increases product cost and complexity
with minimal product reliability and/or safety benefit.  Other competent
engineers would disagree.  Apparantly, standards writing committees for IEC
and CENELEC have stumbled over the same problem.  The authors of EN 61326-1
(and apparatantly some other product standards) did not feel that the
"essential requirements" for Class A Test and Measurement equipment included
EN 61000-3-2 and  EN 61000-3-3.  The authors of EN 61000-3-2 and EN
61000-3-3 disagreed.

According to standards hierarchy, the authors of EN 61000-3-2 and -3-3 win
out.  

That's great, but it doesn't clear up the conflicting standards and we've
already seen that it isn't clearly solved by "essential requirements" type
thinking.  I think that the "essential requirements" type of solution only
works when you could ask 100 EMC engineers about a requirement and get the
same answer more than, say, 95 times.  This standard does not fall into that
category (as witnessed by all of the confusion).  I would assert that the
argument over this standard has precipitated because most EMC engineers DO
UNDERSTAND essential requirements.  This is what leads them to question the
standards.

As a design engineer, I do not have the power to go to my power supply
manufacturers and demand power factor corrected power supplies.  My power
supply manufacturers are very cost competetive and will wait for a VERY
clear system of regulatory mandates before they take the risk of increasing
the cost and complexity of their power supplies.  Also in our cost
competetive market we cannot always afford a custom power supply.  It seems
to me that the confusion and fighting over this standard initially slowed
down the availability of power factor corrected supplies which put an
availability crunch on quite a few designers.  That is where a clear
regulatory mandate would help.

In the end, I don't think that we're waiting for the regulatory agencies to
make our decisions for us.  I think we're waiting for them to make their own
decisions for themselves (with our input).   When they are clear in their
decisions, it helps to level the competetive playing field among products.
When they take on the authority of regulation, they take on the
responsibility of being clear in their mandates.  (Anybody else who is a
parent would understand that one.)

I feel better.  This will be my last email regarding this thread (promise)
(collective applauase from the group)

Have a good one :-)

Chris

> -Original Message-
> From: Wagner, John P (John) [SMTP:johnwag...@avaya.com]
> Sent: Wednesday, October 11, 2000 10:55 AM
> To:   'EMC-PSTC - forum'; 'Jim Eichner'
> Subject:  RE: Standards hierarchy
> 
> 
> I'd like to throw my two cents worth in here.
> 
> First, compliance with a national/international standard or regulatory
> regime does not guarantee adequate product performance or safety.  That is
> the responsibility of the manufacturer.  The standard(s) gives guidance to
> achieve that acceptable level of performance and compliance with it
> acceptable to a regulatory regime or authority provides a legal basis to
> market the product.
> 
> Don't look to regulatory authorities to manage your compliance or
> EMC/Safety
> design goals.
> 
> John P. Wagner
> AVAYA Communication
> 11900 N. Pecos St, Room 2F58
> Denver CO  80234
> email:  johnwag...@avaya.com
> phone:  303 538-4241
> fax:  303 538-5211
> 
> > --
> > From:   Jim Eichner[SMTP:jim.eich...@xantrex.com]
> > Reply To:   Jim Eichner
> > Sent:   Tuesday, October 10, 2000 4:45 PM
> > To: 'EMC-PSTC - forum'
> > Subject:RE: Standards hierarchy
> > 
> > 
> > To summarize and conclude this thread:
> > 
> > 1. If you ignore all consideration except the rules for CE Marking and
> the
> > EMC Directive, and if you have a product family standard that does not
> > call
> > out any other standards (for example EN61000-3-2), and if that product
> > family standard has been published in the OJ, then it would seem that
> you
> > are in compliance with the EMC Directive if you apply only that standard
> > (since it provides a presumption of conformity).
> > 
> > 2. Doing the above would be a bad idea because...
> > 
> > a) The EC has not got it's act together.  With one hand they publish a
> > standard in the OJ and with the other hand they say the standard isn't
> > sufficient.  According to what Gert said, it sounds like the EC will be
> > working with CENELEC to correct this situation, so it is short sighted
> to
> > take the easy road now if you'll just have to take the longer road later
> > anyway.
> > 
> > b) There may b

RE: PCB temp ratings, etc...

[Peter Tarver]

Richard -

Then the answer is no.  The MOT, as Pete Perkins pointed out, establishes
the test points for thermal conditioning, but solder resists are then tested
in conjunction with the PWB only for flammability classification.

Regards,

Peter L. Tarver, PE
ptar...@nortelnetworks.com


-Original Message-
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com]
Sent: Wednesday, October 11, 2000 6:11 PM


You are correct. I used the wrong term. I should have said the solder resist
coating. Is this coating included in the temperature ratings?

Richard Woods

--
From:  mike harris [SMTP:tecco...@i-cafe.net]
Sent:  Wednesday, October 11, 2000 11:25 AM

Hi Richard & Peter,
 
Richard, I wonder if  you are calling the solder resist coating as
conformal coating?
 
Mike Harris/Teccom

DC circuits

[Scott Lemon]

Hello Group,

I have a good idea (first hand knowledge) of what UL looks for with respect
to dc supply circuitry 

RE: PCB temp ratings, etc...

[WOODS]

You are correct. I used the wrong term. I should have said the solder resist
coating. Is this coating included in the temperature ratings?

Richard Woods

--
From:  mike harris [SMTP:tecco...@i-cafe.net]
Sent:  Wednesday, October 11, 2000 11:25 AM
To:  Peter Tarver; emc-p...@ieee.org
Subject:  Re: PCB temp ratings, etc...

Hi Richard & Peter,
 
Richard, I wonder if  you are calling the solder resist coating as
conformal coating?
 
If so, I expect that the resist coating is ignored for any PWB
ratings and insulation properties.
 
My understanding is that conformal coating is a completely other
issue from resist coating.
 
Mike Harris/Teccom

-Original Message-
From: Peter Tarver < ptar...@nortelnetworks.com
 >
To: emc-p...@ieee.org   <
emc-p...@ieee.org  >
Date: Wednesday, October 11, 2000 8:31 AM
Subject: RE: PCB temp ratings, etc...



You're welcome, Richard. 

MOTs are developed for a copper clad industrial laminate and
verified by certain tests on a finished PWB.  Conformal coatings are not a
normal part of this process, though I suppose a board house could ask for
such considerations to be made for a selection of coatings.

According to the Guide Card information for UL's CCN QMJU2,
conformal coatings are evaluated for their dielectric properties and effects
on flammability of a finished board after "environmental, humidity and
thermal conditioning," but I don't remember the details of the test program.
I don't know if it matters whether the coating discolors, so long as it
successfully completes the test program, though, as an end-product
manufacturer, I'd be suspicious of just how good a material it was and talk
this over with the supplier and maybe do a few more tests, if the mandate
from my employer allowed for that.  If the coating bubbled or adhesion to
the PWB surfaced failed, I'd say it was no good for the application.

Regards, 

Peter L. Tarver, PE 
ptar...@nortelnetworks.com 


-Original Message- 
From: wo...@sensormatic.com [ mailto:wo...@sensormatic.com
 ] 
Sent: Wednesday, October 11, 2000 12:59 PM 

Pete thanks for your reply. I have noticed that the
conformal coating on 
some boards begins to discolor when subjected to continuous
high 
temperatures. In some samples, the coating begins to darken,
bubble and 
delaminate from the surface. Is the conformal coating
considered when 
setting the rated MOT? 

Richard Woods 


---
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 Richard Nute:   ri...@ieee.org

RE: DoC & TCF

[Bailey, Jeff]

Hi Richard,

AB uses the TCF route quite frequently and they list their DoC's online.
Try going to http://www.ab.com/certification/ce/docs/index.html and look at
a couple of DoC's through
the links found there.  It won't provide you with the rules for wording are
adhered to
or not but it may give you a start.


Jeff Bailey 
Compliance Engineering 
SST - A Division of Woodhead Canada 
Phone: (519) 725 5136 ext. 363 
Fax: (519) 725 1515 
Email: jbai...@sstech.on.ca 
Web: www.sstech.on.ca 


All comments contained in the message are my own and do not necessarily
express the views of SST/Woodhead Canada Limited. 


-Original Message-
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com]
Sent: Wednesday, October 11, 2000 8:25 AM
To: emc-p...@majordomo.ieee.org
Subject: DoC & TCF



I have seen several Declarations of Compliance when harmonized standards are
used, but I don't recall seeing one where the TCF route was followed for one
or more essential requirements. What wording is used on DoC to note that a
Competent/Notified Body rendered an opinion that a product complies to some
particular essential requirement by using a non-harmonized standard?
 
Richard Woods

---
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Re: PCB temp ratings, etc...

[mike harris]

Hi Richard & Peter,

Richard, I wonder if  you are calling the solder resist coating as conformal 
coating?

If so, I expect that the resist coating is ignored for any PWB ratings and 
insulation properties.

My understanding is that conformal coating is a completely other issue from 
resist coating.

Mike Harris/Teccom
-Original Message-
From: Peter Tarver 
To: emc-p...@ieee.org 
Date: Wednesday, October 11, 2000 8:31 AM
Subject: RE: PCB temp ratings, etc...


You're welcome, Richard. 

MOTs are developed for a copper clad industrial laminate and verified by 
certain tests on a finished PWB.  Conformal coatings are not a normal part of 
this process, though I suppose a board house could ask for such considerations 
to be made for a selection of coatings.

According to the Guide Card information for UL's CCN QMJU2, conformal 
coatings are evaluated for their dielectric properties and effects on 
flammability of a finished board after "environmental, humidity and thermal 
conditioning," but I don't remember the details of the test program.  I don't 
know if it matters whether the coating discolors, so long as it successfully 
completes the test program, though, as an end-product manufacturer, I'd be 
suspicious of just how good a material it was and talk this over with the 
supplier and maybe do a few more tests, if the mandate from my employer allowed 
for that.  If the coating bubbled or adhesion to the PWB surfaced failed, I'd 
say it was no good for the application.

Regards, 

Peter L. Tarver, PE 
ptar...@nortelnetworks.com 



-Original Message- 
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com] 
Sent: Wednesday, October 11, 2000 12:59 PM 

Pete thanks for your reply. I have noticed that the conformal coating on 
some boards begins to discolor when subjected to continuous high 
temperatures. In some samples, the coating begins to darken, bubble and 
delaminate from the surface. Is the conformal coating considered when 
setting the rated MOT? 

Richard Woods 

RE: PCB temperature ratings

[Peter Tarver]

You make an excellent point, Rich.  When I have a marginal temperature
indicated on a component, relative to the MOT of the supporting PWB, I will
add a thermocouple(s) to the PWB surface at the closest "insulated" point
near the solder pad(s) for that component, to round out the data.
Generally, though the design parameters of products vary widely, there is
some heat sinking effects from both the component leads (radiating and
convecting heat into the local environment) and in the PWB's copper.
Indeed, a component's body temperature can well exceed the MOT of the
supporting PWB, while the PWB temperature can run well below the MOT,
particularly if there's a significant ground plane involved.

Regards,

Peter L. Tarver, PE
ptar...@nortelnetworks.com


-Original Message-
From: Rich Nute [mailto:ri...@sdd.hp.com]
Sent: Wednesday, October 11, 2000 12:02 AM

Typically, temperature measurements are made on 
the component, not on the board.  This is a worst-
case temperature that assumes no temperature drop
between the component (along its copper leads) and
the board conductor.


Best regards,
Rich

RE: Standards hierarchy

[Wagner, John P (John)]

I'd like to throw my two cents worth in here.

First, compliance with a national/international standard or regulatory
regime does not guarantee adequate product performance or safety.  That is
the responsibility of the manufacturer.  The standard(s) gives guidance to
achieve that acceptable level of performance and compliance with it
acceptable to a regulatory regime or authority provides a legal basis to
market the product.

Don't look to regulatory authorities to manage your compliance or EMC/Safety
design goals.

John P. Wagner
AVAYA Communication
11900 N. Pecos St, Room 2F58
Denver CO  80234
email:  johnwag...@avaya.com
phone:  303 538-4241
fax:  303 538-5211

> --
> From: Jim Eichner[SMTP:jim.eich...@xantrex.com]
> Reply To: Jim Eichner
> Sent: Tuesday, October 10, 2000 4:45 PM
> To:   'EMC-PSTC - forum'
> Subject:  RE: Standards hierarchy
> 
> 
> To summarize and conclude this thread:
> 
> 1. If you ignore all consideration except the rules for CE Marking and the
> EMC Directive, and if you have a product family standard that does not
> call
> out any other standards (for example EN61000-3-2), and if that product
> family standard has been published in the OJ, then it would seem that you
> are in compliance with the EMC Directive if you apply only that standard
> (since it provides a presumption of conformity).
> 
> 2. Doing the above would be a bad idea because...
> 
> a) The EC has not got it's act together.  With one hand they publish a
> standard in the OJ and with the other hand they say the standard isn't
> sufficient.  According to what Gert said, it sounds like the EC will be
> working with CENELEC to correct this situation, so it is short sighted to
> take the easy road now if you'll just have to take the longer road later
> anyway.
> 
> b) There may be real world problems (and in the worst case a product
> safety
> hazard) associated with an EMC phenomenon addressed by other standards but
> omitted by your product family standard.  In such a situation, liability
> may
> be increased by not having applied the other standards, even though
> technically you didn't have to.
> 
> c) You are flying in the face of standard practice (pun intended).
> Diligent
> compliance people are doing the "right" thing and applying all the
> standards
> that apply, rather than putting on the blinkers and just using their
> product
> family standard (however technically correct or incorrect that may be).
> 
> I'd add a statement to Gert's closing comment that the concept of
> essential
> requirements has not been fully understood yet.  I'd echo say the concept
> of
> product family standards has not been fully understood yet.  The Europa
> web
> site list of harmonized standards is full of wording that implies that
> single standards give presumption of conformity with the EMC Directive's
> essential requirements.  There is nothing to indicate that in many (most?)
> situations it will take a group of standards to fully cover all the
> essential requirements.
> 
> If anyone from the EC or CENELEC has been following this thread, it would
> be
> very helpful to get some clarification as to the current and future "right
> way" to deal with this issue.
> 
> Regards,
> 
> Jim Eichner
> Sr. Regulatory Compliance Engineer
> Mobile Markets
> Xantrex Technology Inc.
> Email: jim.eich...@xantrex.com
> Website: www.xantrex.com
> 
> Any opinions expressed are those of my invisible friend, who really exists
> but is not, by himself, sufficient to give presumption of...oh never mind.
> 
> 
> 
> 
> 
> -Original Message-
> From: CE-test - Gert Gremmen Ing. - CE-mark & more ...
> [mailto:cet...@cetest.nl]
> Sent: Thursday, October 05, 2000 5:20 AM
> To: Jim Eichner; 'EMC-PSTC - forum'
> Subject: RE: Standards hierarchy
> 
> 
> Hello Jim, group
> 
> You are fully right. A standard not covering a certain EMC subject, or
> whitening it out
> due to whatever reason but physical/technical (such as a filament lamp not
> being susceptible)
>  still owes the presumption of compliance but the presumption will not
> hold
> in court.
> 
> After all , presumption is not proof !!
> 
> BTW it happens all the time that we are needing more then one emc standard
> .
> For ITE we need 4:  EN 55022 / EN 55024 / EN 61000-3-2 / EN 61000-3-4.
> 
> We automatically add the other 3 as we conclude that the first one did not
> cover
> certain phenomena.
> 
> What's new here is that the EC does not recognize the right of OJEC
> published standards
> to white out certain test requirements because some lobby decided that it
> was not
> in their interest to cover this.
> 
> In fact the EC is targeting the CENELEC for creating insufficient quality
> standards
> (in this case) and not you as a manufacturer presuming compliance.
> Therefore, you will get away with such a standard - for the time being.
> 
> I think the principal of essential requirements has still not been fully
> understood !!
> 
> Regards,
> 
> Gert 

RE: PCB temp ratings, etc...

[Peter Tarver]

You're welcome, Richard.

MOTs are developed for a copper clad industrial laminate and verified by
certain tests on a finished PWB.  Conformal coatings are not a normal part
of this process, though I suppose a board house could ask for such
considerations to be made for a selection of coatings.

According to the Guide Card information for UL's CCN QMJU2, conformal
coatings are evaluated for their dielectric properties and effects on
flammability of a finished board after "environmental, humidity and thermal
conditioning," but I don't remember the details of the test program.  I
don't know if it matters whether the coating discolors, so long as it
successfully completes the test program, though, as an end-product
manufacturer, I'd be suspicious of just how good a material it was and talk
this over with the supplier and maybe do a few more tests, if the mandate
from my employer allowed for that.  If the coating bubbled or adhesion to
the PWB surfaced failed, I'd say it was no good for the application.

Regards,

Peter L. Tarver, PE
ptar...@nortelnetworks.com


-Original Message-
From: wo...@sensormatic.com [mailto:wo...@sensormatic.com]
Sent: Wednesday, October 11, 2000 12:59 PM

Pete thanks for your reply. I have noticed that the conformal coating on
some boards begins to discolor when subjected to continuous high
temperatures. In some samples, the coating begins to darken, bubble and
delaminate from the surface. Is the conformal coating considered when
setting the rated MOT?

Richard Woods

FW: DoC & TCF

[Jon Griver]

Richard,

DoC is the same except that instead of a list of harmonised standards, you
list the name and address of the Competent Body, and the serial number and
date of the Certificate they issued to you.


Regards,

Jon Griver
VP Quality Assurance
Medson Ltd.



>
> I have seen several Declarations of Compliance when harmonized
> standards are
> used, but I don't recall seeing one where the TCF route was
> followed for one
> or more essential requirements. What wording is used on DoC to note that a
> Competent/Notified Body rendered an opinion that a product
> complies to some
> particular essential requirement by using a non-harmonized standard?
>
> Richard Woods
>
> ---


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RE: EN 475

[dosborn]

Hello Massimo,

The scope of EN475 is as follows:

specifies the characteristics of electrically-generated signals intended for
use with medical devices, either individually or as part of a centralized
system.  This standard applies only if a particular device standard makes
reference to it.

I would suggest that you might want to contact your TAG or shadow group to
IEC 62A and order a copy of the CD1 of IEC 60601-1-8, the collateral
standard for alarms.   There is a great deal of guidance information
available in this document.  CD2 should be out at the end of the year.  

Alarms are used whenever medical electrical equipment needs to give the
operator (or other persons) awareness, or expects prompt or immediate action
from the operator (or other persons).  

Your situation certainly seems to indicate than an alarm should be
considered.

Best regards,

Dave Osborn
Agilent Technologies
Secretary, ISO TC 121/SC3
Co-convenor, ISO TC121/SC3 - IEC TC62A JWG2 on Alarms
dosb...@agilent.com or
d.g.osb...@ieee.org
+ 1 978 659 3178
fax +1 978 685 5624 

-Original Message-
From: massimo.polign...@esaote.com [mailto:massimo.polign...@esaote.com]
Sent: Wednesday, October 11, 2000 6:16 AM
To: emc-p...@majordomo.ieee.org
Subject: EN 475



The European standard EN 475 (1995) concerns "Medical Devices.
Electrically-generated alarm signals". Does anybody know what kind of alarm
are considered? Is it applicable to warning displayed on a monitor to
inform the user that a certain hazardous situation has been reached during
a diagnostic exam?

Thanks
m.p.

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


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DoC & TCF

[WOODS]

I have seen several Declarations of Compliance when harmonized standards are
used, but I don't recall seeing one where the TCF route was followed for one
or more essential requirements. What wording is used on DoC to note that a
Competent/Notified Body rendered an opinion that a product complies to some
particular essential requirement by using a non-harmonized standard?
 
Richard Woods

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RE: PCB temp ratings, etc...

[WOODS]

Pete thanks for your reply. I have noticed that the conformal coating on
some boards begins to discolor when subjected to continuous high
temperatures. In some samples, the coating begins to darken, bubble and
delaminate from the surface. Is the conformal coating considered when
setting the rated MOT?

Richard Woods


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RE[2]: comparison of ESD per MIL - 1686B to EN61000-4-2

[Geoff Lister]

Sorry folks,
It seems you cannot go straight to the results screen :-(

Try
http://astimage.daps.dla.mil/quicksearch/
and insert 1686 in the Document Number box.

regards,
Geoff Lister
Senior Engineer
Motion Media Technology Ltd.
http://www.motion-media.com 

-Original Message-
From: Geoff Lister [mailto:geoff.lis...@motion-media.com]
Sent: 11 October 2000 09:43
To: 'Michael Taylor'; emc-p...@ieee.org
Subject: RE: comparison of ESD per MIL - 1686B to EN61000-4-2



Michael,
I could not find revision B of the spec, but
revision C is available as a free download
from the following address.
Regards,

Geoff Lister
Senior Engineer
Motion Media Technology Ltd.
http://www.motion-media.com 



http://assist.daps.mil/eAccess/index.cfm?ident_number=37095

-Original Message-
From: Michael Taylor [mailto:mtay...@hach.com]
Sent: 10 October 2000 18:32
To: emc-p...@ieee.org
Subject: comparison of ESD per MIL - 1686B to EN61000-4-2



Does any one have Mil Std 1686B handy???  Need to compare test levels
between Mil Std 1686B, Class 3a and EN61000-4-2.
Any help will be appreciated.
M. Taylor
Hach Company
Loveland, Colorado

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RE: Australia Safety

[Kevin Richardson]

Hi Richard,

You should be able to piece together a reasonably full answer from the
responses you have received this far I think but I may fill in some holes
for you.

Approval of stand-alone "plug-pack" or "brick" type power supplies as used
with laptop computers are indeed required to be "approved" in both Australia
and NZ.

In Australia, the various Australian State electrical regulations classify
these devices as "Declared Articles".  All Declared Articles are required to
be approved under the regulations by  one of the Australian State designated
Electricity Authorities.  Approval granted by any one State authority is
accepted in all other Australian States and Territories.  If the device is a
transformer type power supply it would be required to comply with AS/NZS
3108.  If it is a pulse mode type power supply it would be required to
comply with AS/NZS 3260 or AS/NZS 60950 (the latest edition of AS/NZS 3260 -
renamed to be more identifiable it is based on IEC 60950).  The device would
be required to be labelled with the approval number once granted etc.

For NZ, it is fairly similar in that they are also considered as "Declared
Articles" and the same standards apply however the "approval" is gained from
the "Office of the Chief Electrical Engineer" within the Safety branch of
the NZ Ministry for Economic Development (previously called the NZ Ministry
of Commerce).  The device must also be labelled with the approval number.

In terms of test reports, AS/NZS 3108 is reasonably unique in its
requirements to Australia and NZ.  As such, testing is usually carried out
in Australia although there are some overseas labs which can test to this
standard.  I believe you would be reasonably familiar or at least are well
aware of AS/NZS 3260 etc.  Any CB report to AS/NZS 3260 (naturally being a
CB report it would include national deviations for Australia/NZ etc) would
be acceptable in both Australia and NZ for pulse mode type units.

Best regards,
Kevin Richardson

Stanimore Pty Limited
Compliance Advice & Solutions for Technology Products and Services
(Legislation/Regulations/Standards)
Ph:   02-4329-4070   (Int'l: +61-2-4329-4070)
Fax:  02-4328-5639   (Int'l: +61-2-4328-5639)
Mobile:  04-1224-1620   (Int'l: +61-4-1224-1620)
Email:k...@compuserve.com
 kevin.richard...@ieee.org
 k...@technologist.com (alternate internet)


-Original Message-
From: owner-emc-p...@ieee.org [mailto:owner-emc-p...@ieee.org]On Behalf
Of wo...@sensormatic.com
Sent: Tuesday, 10 October 2000 11:02 PM
To: emc-p...@majordomo.ieee.org
Subject: Australia Safety




Is safety certification mandatory in Australia or New Zealand for external
power supply "adapters" such as the types used with laptop computers? If so,
what is the mandatory safety standard and which agency certifications are
accepted?

Richard Woods

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EN 475

[massimo . polignano]

The European standard EN 475 (1995) concerns "Medical Devices.
Electrically-generated alarm signals". Does anybody know what kind of alarm
are considered? Is it applicable to warning displayed on a monitor to
inform the user that a certain hazardous situation has been reached during
a diagnostic exam?

Thanks
m.p.

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


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RE: comparison of ESD per MIL - 1686B to EN61000-4-2

[Geoff Lister]

Michael,
I could not find revision B of the spec, but
revision C is available as a free download
from the following address.
Regards,

Geoff Lister
Senior Engineer
Motion Media Technology Ltd.
http://www.motion-media.com 



http://assist.daps.mil/eAccess/index.cfm?ident_number=37095

-Original Message-
From: Michael Taylor [mailto:mtay...@hach.com]
Sent: 10 October 2000 18:32
To: emc-p...@ieee.org
Subject: comparison of ESD per MIL - 1686B to EN61000-4-2



Does any one have Mil Std 1686B handy???  Need to compare test levels
between Mil Std 1686B, Class 3a and EN61000-4-2.
Any help will be appreciated.
M. Taylor
Hach Company
Loveland, Colorado

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Re: Australia Safety

[Barry Esmore]

Hi Richard,

It's certainly mandatory for Australia, but was not mandatory for NZ last time 
I looked. 

The standard should be AS/NZS 3108, or for IT equipment you may use AS/NZS 3260.

Let me know if you need further assistance.

Regards
Barry Esmore

AUS-TICK
(The Australian Compliance Professionals)

Phone: + 61 3 9886 1345
Fax: + 61 3 9884 7272
Email: bar...@melbpc.org.au


  - Original Message - 
  From: wo...@sensormatic.com 
  To: emc-p...@majordomo.ieee.org 
  Sent: Tuesday, October 10, 2000 11:02 PM
  Subject: Australia Safety



  Is safety certification mandatory in Australia or New Zealand for external
  power supply "adapters" such as the types used with laptop computers? If so,
  what is the mandatory safety standard and which agency certifications are
  accepted?

  Richard Woods

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PCB temp ratings, etc...

[Pete Perkins]

PSNet,

PWB's are one form of plastic insulating materials.  They must endure for a
long time without giving up the properties that make them good insulators or
enclosures for insulators.  In the long term the volatiles evaporate away
and the molecular structure breaks down giving way to failure.  This can
take a very long time, so accelerated aging is used to determine the useful
life of the material.

The Maximum Operating Temperature (MOT) given in the UL Recognition for any
plastic material represents the temperature at which that material will
survive to a half life for the worst case of any one of several mechanical
and electrical performance factors.  The controlling factor might be due to
a mechanical stress (e.g. bending or flexing) or electrical (e.g. dielectric
breakdown).  The tests are done at several temperatures and the performance
factors are measured at regular intervals.  The results are plotted on
semi-log paper - look thru UL 746E to see examples - and the results are
extrapolated to 100K hrs life and the temperature noted - this becomes the
MOT.

The testing can take a long time - up to 10k or 15k hrs - which delays the
introduction of new materials until the rating is in hand.

I've never found an easy relationship to the temperature numbers used for
other purposes - including the glass transition temperatures assigned to
PWBs...  Maybe higher is better in both cases, but...

Whether or not the traces stick to the PWB material or it delaminates from
the ground planes is determined separately by testing of board samples from
each board shop.  The conditioning temperature for this testing is
determined by the MOT assigned to the PWB material.

So, don't make too much of the MOT, nor dismiss it lightly.  The
requirement in most standards is that each plastic material, including the
PWB, must stay within its MOT under normal and fault conditions.  (We
measure the insulation temperature in transformers for this very purpose.)
It's the evaluators job to show that is true...  Thermocoupling either the
components or the board is only a proxy for showing compliance; if a
component is hot perhaps both should be measured.  I normally use an IR
probe to scan for hot spots and TC the hottest of them (I also offer the
[calibrated] IR probe to the investigating engineer from the NRTL to check
us out)...

Well, I'll not bore you with any horror stories, but surprises abound when
doing thermal testing...

  br, Pete

  Peter E Perkins, PE
  Principal Product Safety Consultant
  Tigard, ORe 97281-3427
  503/452-1201 fone/fax
  p.perk...@ieee.org


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Job Posting - Compliance Engineer - Santa Barbara, CA

[Michael Garretson]

Forwarded for Nazeeh Shaheen  - please do not hit
reply to respond - redirect messages to Nazeeh Shaheen


Position:
Compliance Engineer
ITE Equipment
BSEE or equivalent
Familiarity with LAN/WAN technologies
Product Safety
EMI/EMC
Network Attachment
NEBS

Location:
Occam Networks 
4183 State Street
Santa Barbara, CA 93110

Company:
Occam Networks is an early stage start up which received initial Series A
funding in Feb 2000.  Occam Networks' mission is to be the leading provider of
low-cost, high-function IP access devices to the service provider market.

Perks:
Absolute coolest company to work for.  No egos, just brilliant people. 
Plus...
pre-IPO stock options, 
very casual dress,
bring pet to work atmosphere, 
telecommute friendly, 
weekly massage, 
team building events, 
endless snacks and drinks
paid health club membership, 
very progressive and supportive management
educational reimbursement 
relocation assistance
401K
the typical health dental vision life LTD stuff



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