At 02:55 PM 9/17/99 -0400, Bailey, Jeff wrote:
>
>Hello group,
>
>I am trying to find a basic document from UL and or CSA regarding the legal
>requirement of
>UL or CSA listing. I am thinking along the same lines as the European LVD.
>Can anyone
>offer insight as to whether this documentation e
At 03:01 PM 9/13/99 +0100, carlos.perk...@eu.effem.com wrote:
>
>Hello Group,
>
>Can anyone tell me if CE marking of electrical and electronic products is
>acceptable to the Mexican authorities?
>
>What tests in addition to the ENs would be necessary?
>
>Many thanks.
>
>Carlos Perkins.
CE marking
At 04:54 PM 9/1/99 -0300, Muriel Bittencourt de Liz wrote:
>
>Dear Members
>
>I'd like to solve a doubt.. suppose the following:
>
>"I have an electrical installation in a house. The feeding is with
>three-phase and one neutral conductors. If I connect a TV and a blender
>in the same phase, the bl
At 12:37 PM 8/31/99 -0600, JENKINS, JEFF wrote:
>
> Does anyone know if there are "laws" that
> require semiconductor processing equipment
> and other types of industrial equipment to
> conform to FCC 47 CFR Part 18? From time
> to time we get inquiries about this and
> we're wondering what
At 03:39 PM 8/20/99 -0600, POWELL, DOUG wrote:
>
>Hello all,
>
>I have a very innovative engineer who has come up with a design idea that
>uses concrete as an insulating compound in a very large inductor for a 200
>kW switching power supply. Yup, this is the stuff you buy down at the local
>buil
I'm reading this thing and
1. Read 645-5 one way and it might be read
to require ANY ITE equipment on a raised
floor environment to have DP type cables.
As in the second to last para that states
"Section 645-5(d)(5) requires interconnecting
cables used under raised floors
John,
I can only try to relate safety with the extensive
use of "shall" with ISO certification having gone
through the lead auditor course nightmare.
For ISO 9001, there's about 136 "shalls" listed.
Get all your "shalls" right and you *will get* the
certification. Miss a "shall" and you
I apologize if this is really off topic ...
Having a *friendly* discussion about hydrogen
fuels cells replacing commercial power. I'm
taking the "you got to be kidden me!" side.
Okey. Sometime in the future, imagine this
actually happens (stop laughing). Hydrogen
is pumped out to everyon
At 10:36 AM 7/13/99 -0700, Leslie Bai wrote:
>
>
>Dear members,
>
>Anyone there can share the experience to measure
>cables' impedance thus to identify whether a BNC
>is a 50 ohm or 75 ohm cable.
>
>Thanks,
>Leslie
Quick and dirty method with a high amount
of confidence that you have RG-58 or RG
Someone may have already suggested
this but here goes ...
>(1) Fabricate an EMC story to relate the cause (Flushing toilet) to the
>effect (Rebooting PC).
A major current draw from the same circuit to which
the PC is connected appears to be happening at the
same time the toilet is fl
Hi George,
A web search showed ...
ESRI: Environmental Systems Research Inst., Inc.
GIS: Geographic(al) Information System(s)
Most likely a private thing for interfacing
particular types of information.
Regards, Doug McKean
At 08:57 AM 7/7/99 -0400, geor...@lexmark.com wrote:
>
>I
Aren't there 0.156" connectors by Amp or Molex?
At 01:21 PM 7/7/99 -0400, Beard, Susan wrote:
>
>Anyone know of any connectors with 0.1" spacings that survive a 2000 volt
>rms hipot requirement?
>
>Susan Beard
-
This message is coming from the emc-pstc discussion list.
To cancel your
Hi George,
After posting a similar question to Treg about a year or more ago,
and doing some research, I maximized the spacings and incorporated
them into the design practices at a former company. I believe
these spacings will carry your product to just about anywhere
in the world (which wa
Hi Joe,
Personally, in my humble opinion, I'd have to
question what would happen to my end user if
for any reason what so ever the AC adapter
shorted over to the 7vdc side.
This is a personal opinion. I try to stand up
on a soap box about matters like this and usually
lose. But, in my o
Hi Peter ...
At 02:41 PM 6/28/99 +0100, PETER PHILLIPS wrote:
>
>Dear group,
>
>Has anybody heard about the term EFFECT relating to EMC and environmental
>testing combined.
No. I believe there's an aircraft test that's titled
something like "Magnetic Effects". But I have no idea
what that
Hi Lisa,
I've got to ask this, so here's goes ...
Is the cable that has to be ferrited:
1. Part of the system that your company sells?
Or at least sourced by your company through
something like the Installation/Users Manual
with either your P/N or a mfrs P/N?
2. A cable that th
At 03:30 PM 6/23/99 -0400, WOODS, RICHARD wrote:
>
>Can you recommend a lab in the USA that can perform failure analysis on an
>electrolytic capacitor?
In a past life I've had caps analyzed.
Usually the mfr of the cap is very willing
to do the job. And they were very helpful.
-
Th
At 11:18 AM 6/17/99 +1000, you wrote:
>
>Greetings and Salutations! I was wondering if this could be mailed out via
>the epc-pstc channels.
>
>I want to know if anyone is doing any work in "near/ far field correlation
>to commercial EMC standard limits" area and possibly correspond with them
>wit
Thanks to all the responses.
A suggested off line contact with one of the
persons involved with the limits produced
confirmation of much of what has been said.
If I may take the liberty to paraphrase his
response - it was determined to prevent radio
interference at an agreed upon distanc
Alright, I'll take a stab ...
At 02:30 PM 5/12/99 -0700, Allen Tudor wrote:
>
>Greetings group,
>
>I am trying to draw a parallel between transmission line theory and
radiated emissions.
>
>From what I understand, a transmission line can be terminated at the
source or the load with an impedan
Hope no one's offended with this ...
I'm remembering a story a prof at school
who worked at Bell Labs imparted on us
one day in class.
Seems as though, long ago, he was working
on some system to be installed in some
remote site way out in the mid-West.
Someone suggested testing the cables
My two cents intertwined below ...
At 01:38 PM 4/21/99 -0400, Scott Douglas wrote:
>Hi All,
>
>Recently an interesting discussion came up about harmonics. A general
>disagreement followed. We hope you all can offer some insight and perhaps
>help us settle the question.
>
>The question is numberin
At 08:43 AM 4/19/99 -0800, ed.pr...@cubic.com wrote:
>But Lou, it would be "safe" smoke!
>
>Ed
As long as you don't *inhale* ...
-
This message is coming from the emc-pstc discussion list.
To cancel your subscription, send mail to majord...@ieee.org
with the single line: "unsubscribe
Well, here's some basic stuff from my experience.
Conductive paint cannot be used for "earth bonding".
It can be used only for shielding purposes. In other
words, don't expect to either a. pass large amounts
of current through it, b. assume it will always be
a reliable ground path, c. be abl
Lou,
It is impressive and my boss Doug Smith uses it during
some of his seminars. I have tried hitting the coins
in the bag with a hammer several times very near the
antenna - nothing. I even smacked two big screwdrivers
together on the metal near the antenna for several
minutes - nothing.
At 08:03 AM 3/8/99 PST, Bailin Ma wrote:
>Hi Group,
>
>We have already seen awards for the most misleading ads, worst attire,
>worst films, .
>Why not awards for worst EMC and PS qualities?
>
>Barry Ma
>Morgan Hill, CA 95037
For power supply disasters, I had a -48vdc telco
product at an unna
all should learn from this particular example?
>>
>> Hopefully you don't think it's offensive to ask above questions. I
>am just
>> very curious.
>>
>> Thank you.
>> Best Regards,
>> Barry Ma
>> (408)778-2000 x 4465
>>
>>
To whom it may concern,
Sorry, rather lengthy. I tried to cut it down.
I've finally realized I don't think I fully understand
European approvals and I'll discuss why with two examples.
The first example will go from the *system level* down
to the *sub-system level*. The second example will
At 08:03 AM 3/8/99 PST, Bailin Ma wrote:
>Hi Group,
>
>We have already seen awards for the most misleading ads, worst attire,
>worst films, .
>Why not awards for worst EMC and PS qualities?
>
>Barry Ma
>Morgan Hill, CA 95037
Long ago in another company, I was completing the testing
for a la
At 09:30 AM 3/3/99 -0800, Allen Tudor wrote:
>Clause 5.4.4 of UL 1950, Third Edition specifies that in lieu of creepage
and clearance distance requirements for operational insulation, the
electric strength test for operational insulation (Table 18) can be used.
>
>Does anyone know how to calculate
How about any lasers, Steve?
Regards, Doug
At 09:38 AM 2/17/99 -0600, Steve Grobe wrote:
>I have already had one response asking where we intend
>to sell the product, I know I should have thought of that.
>
>To start with the product would market to the U.S. and
>Europe. The product will c
Isn't this a variation of using the traces as a fusing element
instead of using a real fuse? It's been done, there's nothing
wrong with it until you start *claiming* the traces as a fusible
device. I'm not sure about this, but if you are, don't the traces
themselves have to be tested as if th
At 09:30 PM 1/4/99 -0500, Kevin Richardson wrote:
>
>I am trying to find definitions for two terms:
>a) "Radio Frequency" ie what is radio frequency, and what frequencies are
>recognized as being RF rather than what may be practical for transmission
>purposes ?; and
>b) "radio frequency energy"
Obvious primary but there could be some secondary effects ...
Primary:
Reports, DoCs, TCFs, User manuals, Technical Manuals, etc ...
Secondary:
OEM agreements - that alone could be a huge biggee,
Distributors - exactly what is their role overseas(?),
ISO documents - documentation d
At 07:42 AM 12/11/98 -0600, Mike Mayer wrote:
>
>[...]
>
>="Coding Scheme for Gigabit Ethernet
>= PAM-5 (Pulse Amplitude Modulation 5 Levels)
>= 2 Bits per symbol ( => 4 bit combinations or levels)
>= Symbol Rate 125 Mbaud/sec
>= Bit Rate per pair 250 Mbits/sec
>= Bit Rate using 4 pairs 10
At the following webpage,
http://www.scope.com/whitepap/white19.htm
it is briefly discussed the concern over pushing 1000BaseT down Cat5.
This concern has raised the possibility of introducing another version
of Cat5 cable indicated as Cat5-E.
I quote ...
"Can Better Cabling Help?
Sinc
I'll concur with Don, but as discussed at the IEEE 802.3z Gigabit
Ethernet Task Force meeting in Irvine, California on March 10-14,
1997, this was apparently briefly discussed.
The full text is at
http://grouper.ieee.org/groups/802/3/z/public/minutes/Irv0397.txt
I quote only the important pa
At 11:26 PM 12/1/98 -0600, Mel Pedersen wrote:
>
>Anyway, the intent here is that the insulation not be damaged from an
> overvoltage from the TELECOMMUNICATIONS NETWORK, and I believe that the
> "overvoltages" in mind included lightning strikes.
Well, just my 1 cent worth would be that the "int
At 12:39 PM 11/30/98 -0800, ed.pr...@cubic.com wrote:
>Hi Listmembers!
>
>I recently came across a Lineman's Web site which has a series of three
>pictures showing the near electrocution of a man who climbed a power pole
>topped with a 16.6KV 3 phase power bus. I think the content is reasonably
Sorry this is long, buuut ...
I recommend going to
http://www.northland.cc.mn.us/Terry_Wiseth/gas%20transport%20part%201/index.
htm
Keep in mind that there are all sorts of hyperbaric chambers
available. There are others that are smaller but not capable
of great pressures. The only one I w
At 12:16 PM 11/24/98 -0800, ed.pr...@cubic.com wrote:
>Massimo:
>
>Further complicating the issue is that the Apollo 1 fire ocurred with a
partial pressure O2 rich environment. My guess(!) is that a >1ATM O2 rich
environment would be even more hazardous.
>
>Maybe you can find some hints on this via
At 09:01 PM 11/20/98 GMT, Patrick Lawler wrote:
>On Thu, 19 Nov 1998 11:15:26 -0800, Ed Price wrote:
>
>
>>11.) Douglas McKean
>>The most er ... challanging site where I had products tested was at an
OATS run by Xx when they were just on the other side of the f
It depends upon many things. The best way would
be to profile several configurations (if possible)
of your product to be able to say to a product
manager "double the number of drawers and you'll
put us over by about dB."
If you can insert a number there with quite a
good amount of confidenc
Moshe,
Don't mean to be a real nit pick, but I've been corrected many
times when asking this type of question. You're comparing apples
with oranges. European directives are not standards.
Check to see which safety standard(s) was used for that product
to declare compliance with 89/392/EEC,
Indeed.
The lower 5mW lasers used in some optical transport
systems may seem low. BUT, the beam is concentrated
into an area only a few mm^2 before it manages to get
dispersed. That's an amazing amount of energy for
eye tissue to receive.
A laser rated somewhere just above 20mW can ignit
Sign on the wall of a lab ...
**
**
*- WARNING - *
* DO NOT LOOK INTO BEAM *
* WITH REMAINING GOOD EYE *
**
***
Hi Rick,
The Classes are I (Roman numerals) thru V, I believe.
The lower the better. Chemical lasers are way up there.
To be precise, I think those pointers are rated Class IIIb.
You have to check the laser regs controlled by the FDA to
get the precise limits. It's based on power and freque
I've been getting that same reaction for years from mangers
in regard to domestic Safety Component Recognition versus
a system testing. Same thing for domestic emissions testing.
"I've got all the approvals for everything.
Whaddaya mean I have to get it all tested AGAIN!"
They hear compone
At 02:33 PM 10/28/98 +0100, andreas.tho...@toshiba-teg.com wrote:
>Dear All,
>
>I like to ask you for your comment regarding following case:
>
>If there is a portable IT product which bottom surface can become hot
>(around 49°C) during use, would you recommend to put a warning label onto
>the produ
Ok, you guys got me. I didn't think it's take this long.
I confess. The gig's up. I'm the one ...
About 15 years ago in another company far away, I brought
a product into a reputable lab to be tested. It "passed",
if I remember correctly, by -0.5 dB.
The confidence "acid test" back then was (
Massimo,
1) I have a small amount of experience with this. Symmetry will
play an important part. In some bus designs, designing in
added lengths to various traces may be necessary to keep an
equal prop delay among the traces of the bus.
2) EMI behavior depending on unequal signal
All I found was the following from 1996 ...
http://www.ssnewslink.com/html/governme.html
At 09:44 AM 10/9/98 -0400, Matejic, Mirko wrote:
>Can somebody confirm information I picked on the radio that each Shuttle
>launch causes a major damage in the Ozone layer?
>
>Mirko Matejic
-
This
Gary,
I'm not exactly sure what it is you're looking for
but TR-499 is the generic spec and states 48vdc nominal,
high, low, and transients.
As to how the 48vdc is supplied within a CO, I *believe*
that's up to the individual CO. Case in point, the COs
I've seen (and I haven't seen many) u
Don,
Until I contested this arrangement, I routinely had 48vdc equipment
tested
for the conducted emissions on the AC side (input side) of a seperate
AC-to-DC
power supply (an HP if I remember correctly) that powered the shelf.
That
HP supply was part of the test equipment setup and not part
You could probably spend the rest of your life trying to
get a correct answer from this question since litigation
*usually* follows the "deep pocket" method with recovering
a settlement. I've seen some pretty wierd (IMHO) cases
that didn't seem to follow logic until the deep pocket
theory is
I had to deal with the LA lab once. They at that
time were not an NRTL, but in order to sell products
of the UL-1950 category within LA county, one was
required to have an NRTL or this LA Lab's approval.
This was quite a while ago so things may be different
now. But, there's a situation wher
Well, this has been rather informative, but
the CB scheme as I understand it is specific
about exactly what test data is involved.
Right now, it's mainly safety related
testing, no?
In other words, you could be testing a product
in country A who participates in the CB Scheme.
The tests may
Just a suggestion, but would it be too much to ask people
who did some of the tremendous studies in simulations
and analysis scenerios with printed circuit boards
to do best case and worst case scenerios with a RANGE
of FR-4 values and then to have the Dk of the board
for the frequencies of in
Hi Ron,
Answers below ...
Wismer, Ronald S. wrote:
>
> Our company(In the US) wishes to purchase an AC/DC power supply from
> an outside vendor(From overseas). We then, plan to add some fusing
> circuitry, an enclosure, and a terminal block so that it mechanically
> meets our needs. The vend
Richard Haynes wrote:
>
> Doug,
> Thanks for adding your important two cents. Could you show us an example
> with the necessary conversions numbers. Also there is the concept of
> equilivalents/mole where the number of equivalents is effectively the
> valence, i.e. 2 for Cu(+2). There are some cas
Hope you guys don't mind my two cents but I hope you're
assuming something here which I don't see. The units for
the Gas Constant used in the Arrhenius' equation is
R (gas constant) = J/mol*K or cal/mol*K
That means Ea (activation energy) must be in units J/mol, or cal/mol.
If the unit
Peter E. Perkins wrote:
>
> Brian & PSNet...
>
> Regarding your question as to whether certification is required on
> products 'over there' or not...
>
> In the USA, since the publication of the OSHA CFR 1910.303
> Certification requirements, there has been such for electrical eq
knigh...@exchange.sandiegoca.ncr.com,Internet writes:
>RE: my request of a couple of weeks ago for EMC compliance horror
>stories:
>
> Thanks to all who shared humorous and real horror stories. I have
> shared most of them with my management.
>
> While the stories of good intentioned designs gone
r. Or am I all wet
about this one?
Regards, Doug
Richard Haynes wrote:
> Doug,
> What distribution did you use for the calculation. This may be a major
> assumption and the AF can vary by several times?
> Richard Haynes
>
> From: Douglas Mckean
> >Not sure I have this righ
Not sure I have this right but why not just do some
accelerated temp testing with a sample quantity?
I calculate that 16,006 hrs (95.27 weeks) at 20 degrees C
reduces to just 6.01 weeks at 65 degrees C.
Regards, Doug
Jon Ilseng wrote:
>
> For the reliability engineers out there, I am lo
At recent symposium in Santa Clara, I talked to some length
with one of the speakers about round holes in shielding for
ventilation. For all the equations I've seen and tried to
verify, they really don't pose a problem with the work I've
done. But, that's strictly my experience and that in it
chasgra...@aol.com wrote:
>
> Hello!!
>
> I have a question regarding dual manufacturers names on a regulatory
> label.
>
> >From an EMC perspective:
>
> The situation is that Company A wishes to buy product from Company B
> and resell using Company As name and model number.
>
> In order to s
of the the ATM card?
>
> Regards,
>
> Randy Flinders
> EMC Test Engineer
> Emulex Network Systems
>
> Chairman
> Orange County Chapter
> IEEE EMC Society
> --
> From: Douglas Mckean
> Sent: Tuesday, July 07, 1998 6:57 PM
> To: emc-pst
How about ...
The one where some creative types got some EMI(?) equipment
to monitor the keystrokes of people at an ATM?
Story goes that they sat in a van in a parking lot by the
bank with antennas focused on the ATM. Once you entered
in your numbers, they could translate the EMI signature
to k
Yes, Chris.
Quite amusing. Then, of course, there's
the famous "fly in the microwave" debate ...
Chris Dupres wrote:
>
> Hi Keith.
>
> As we wander round this world of Electro-fizz, pop and 2dB-over-limit, we
> come across all sorts of strange EMC behaviour, some directly witnessed,
>
Correct me if I'm wrong, but won't the FCC accept
CISPR 22 test results from overseas test sites as
long as the test site is listed with the FCC?
Regards, Doug
geor...@lexmark.com wrote:
>
> There are no immunity requirements for FCC, ESD or otherwise.
> The FCC radiated and conducted EMI l
Energy Star is a program setup by the EPA.
Originally, urban legend has it that some
beaurocrat somewhere in the bowls of the
US government multiplied the number of
PCs to be bought for Federal Employees
by the wattage of the average device and
concluded that it was unacceptable.
The monito
I'd have to underscore Keith's responses with
just a few of my own -
> Q: Finding the EM in a circuit using network analysis:
About 2 years ago I looked into software for EMC work.
I was interested in loading in artwork of a pcb
(gerber files, Orcad, whatever) for analysis - not system
level
Oh, ok, have had experience with both styles with power
supplies end mounted and middle mounted. Personally,
from a noise reflection point of view as far as the
backplane power traces, I would prefer a middle mounted PS
system. But, that's debatable.
The middle mounted rack did far better EM
We have a Pacific "Smart Source" P/N 360-AMX UPC32
Voltage Freq
Input: 208vac 60 Hz
Output: totally programmable
Regards, Doug
WOODS, RICHARD wrote:
>
> HP produces a very nice line of power supplies where you can program the
> voltage, current and frequencies.
>
> >
Hi Gary,
Have to ask a dumb question.
Do you mean a "rack" as in a 7 foot 19 inch style floor standing "rack"
that is part of a bay in something like a CO, or do you mean a "shelf"
that's mounted in 7 foot high 19 inch wide "rack"?
Sorry, confused ...
Regards, Doug
Gary Allen wrote:
>
Just a suggestion ...
OFF = round circle with a dark inside.
ON = round circle with a white inside
As far as flashing is concerned, I have no idea.
How about
Slow flashing = round circle with white inside and
just to the right of the symbol,
a series of
Well,
Just for my two cents, 40,000 ft equates to roughly 1/5 the pressure at
sea level or almost 3 lbs/in^2 absolute compared against 14.7 lbs/in^2
at sea level absolute. That leaves any type of plug or wall structure
of the capacitor having to withstand 11 lbs/in^2 across it.
Also, the
I'd just like to say that it was nice to
finally put some faces to the names.
Thought it went very well.
An electrician told me by word of mouth
the proper way to apply wire nuts is:
1) Twist the wires in the direction of twisting on the wire nuts.
2) Twist the wire nut onto the wires.
3) Wrap electrical tape around the wires and nut in the direction
the wire nut was twisted to secure the wir
Could I ask a more general question?
Twist-ons are typically used alot by electricians in all sorts of
wiring applications within the US.
Are electricians outside the US allowed to use twist-ons when
wiring to local code?
Regards, Doug
> -Original Message-
> From: owner-emc-p.
When analyzing printed circuit boards, BOTH clearance AND creepage
are issues. The flat pcb fab (no parts installed or soldered) would
most likely have nothing but creepage issues - distances along
the surface of the board ("as the crow walks").
An assembled pcb with parts that could comprom
George,
Can't say I have had the same experience. But, I have
had experience with two different safety NRTLs each with
their own label. Anytime something did come up I always
referred the issue to the supervisor of the test engineer
of the approval to make the call. My experience was that
Has anyone worked on defibrillators?
My slight reading on the subject has found widely differing limits.
And the milli-amp spec is from the hand only. Especially
the right hand. One reason why long ago, I was taught to work on
tubes with one hand - if current was to pass through you from yo
Thanks for all responses both on and off-line.
Some very funny, but all very informative.
Initially the stack up looks alright without knowing anything else.
Just some curiosity questions:
1) Are there any signal layers in this backplane?
2) Which power plane has the most current/family of ICs/noisy?
From this, you might want to consider assigning layer 1 as
the "outside" l
CTL wrote:
>
> What are the EU requirements for EMC on Optical Multiplex Carrier
> Systems that provide for capacity upgrades?
> What about Safety?
> There are no copper connections to any network. System components are
> transponders, passive optical multiplexers, optical amplifier, and
> wavele
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