Most people use the EM clamp. We test to EN50130-4 alarm system limits:
10V, pulsed and AM modulated. The test is trivial because of the inherent
immunity of Ethernet; be sure you understand the EUT and AE port
partitioning algorithms.
Constructing a CDN that compliant to ANSI/IEEE 802.3/802.3
Good People
I have not been able to find any requirements on the TUV or UL websites for
minimum size requirements of their respective logos (when used as a safety
mark on the recognized/certified product).
Could someone provide a pointer to (agency-published) guidance for logo
dims?
Thanks Much
Although this is not an EMC standard it is related. My lab has been asked to
test our products to the magnetic standards of IATA Packing Instruction 902.
This test determines the ability of a device to change a compass reading. I
have the regulations and know how to do the test, but do not do it
In the very specific case of Medical devices, the newest edition of IEC
60601-1-2 specifies -5 testing at the extreme ends the range of
continuously adaptive supply and in each range of a switched range supply.
Regards,
Brent DeWitt
gunter_j_ma...@embraco.com.br@majordomo.ieee.org on 04/1
Hello Group,
I have been tasked with obtaining A2LA accreditation for my internal (first
party) lab. We have about ten technicians, perform all standard suite of IEC
EMC tests along with vibration, shock, bump and environmental (cold, dry heat,
damp heat) testing.
I have attended ISO 17025 tr
I am not advocating placing an inductor in series with the cap. Circulating
loop currents in the power and ground traces will create emissions, but
those currents can be reduced by use of bypass capacitors or an L-type
filter (capacitor and inductor) in the 5V trace. At least, according to
accepte
Although this is not an EMC standard it is related. My lab has been asked to
test our products to the magnetic standards of IATA Packing Instruction 902.
This test determines the ability of a device to change a compass reading. I
have the regulations and know how to do the test, but do not do it
Hello group,
IEC 61000-4-6 mentions a decision chart on the use of injection method:
1rst question of this chart: are suitable CDN's available?
if YES: use CDN as per 6.2.2
if NO: use other means (e.g. EM Clamp)
My question:
1. Are CDN's used for CE in EN55022 "suitable" CDN's for ethernet
10/10
List
I suppose that EN61000-4-4, 4-5 and 4-6 do not mention the input voltage to
be applied to the EUT during the tests.
For a product with a voltage range, like 198 up to 264Vac (230Vac nominal),
what should be the right value ?
Or do I need to look for the worst voltage case ?
Thank you for y
Amund,
I have encountered similar problems with similarly designed boards. In one
interesting case, I was able to get 30 dB reduction in radiated EMI by
adding a series resistor to a (fairly short) low-frequency clock line. Due
to use of modern devices, its rise and fall times were less than a
n
Not sure this would be a cure in this instance. This is effectively the
same as adding a lossy inductor in series with the cap, which would tend
to negate any benefits of using a cap with lower self inductance.
Bob Wilson
TIR Systems Ltd.
Vancouver.
-Original Message-
From: richwo...@tyc
Years ago in ultrasonic echocardiography instrumentation (the ultrasonics
analog is a wide band receiver listening in the 1-10MHz region down to less
than 10uV, so the digital had better be quiet!) which used a bit slice
architecture system containing Schottky logic with a clock of 20MHz for
contr
Hi,
I have not used a carousel and would not do so without a lot of data to show
that it dose not affect antenna behavior. It has been shown that the terminal
impedance of an antenna changes as it is moved up from 1m above the ground
plane. Similarly, at 3m, it is possible for the presence o
Amund,
That is why I wrote that the leads should hug close to the microprocessor
package. Sort of like a piggy back, that way the lead loop inductance is
at the minimum, since I guess correctly that the Vcc and Gnd pins are miles
apart. I suppose it is not a mass production model, so it is acce
Jeffrey,
You are correct. The standards do not address the usage of multiple
antennas. We have not participated in any Round Robin testing multiple
antennas in the test chamber, so I am not exactly sure what the possible
effects would be in terms of getting accurate and/or repeatable results.
>
Hmmm.
I've read a couple of other replies on this...good suggestions. I have
also read your re-replies which suggest that you have a two layer
"planeless" board.
I understand that you are trying to get an unwanted 156Mhz off of the 5V
line. A couple of thoughts come to mind.
First 156Mhz
Consider adding a ferrite bead in the 5V trace to the microprocessor.
Richard Woods
Sensormatic Electronics
Tyco International
-Original Message-
From: am...@westin-emission.no [mailto:am...@westin-emission.no]
Sent: Wednesday, April 17, 2002 4:50 PM
To: emc-p...@majordomo.ieee.org
Subj
Interesting articles on your web-site, Tim.
>BTW, how about just using a 100 pF capacitor with the 'leads' hugging close
>to the microprocessor package
There's a "mile" from the Vcc pin to ground, that's another problem. No
ground plane, only ground traces which is routed around on the PCB. This
Amund,
In the absence of any layout information that can evaluate the loop
inductances, I suggest you read what I wrote about placing two capacitor in
parallel which can be found on Chapter 3 of my thesis. A link is available
in:
http://www.geocities.com/timfoo6143/index.html
BTW, how about ju
There will be a Northeast Product Safety Society meeting on Wednesday,
April 24, at EMC Corporation's Customer Briefing Center in Hopkinton,
MA. A social hour with light refreshments will begin at 7:00 PM and the
technical meeting will start at 7:30 PM. James Norton, CEO of EMD
Optima, will be p
Correct, the picture is complex. The PCB is 2-layer with signal, 5V-power
and 0V-ref lines routed on both sides. There is no ground layer/plane. There
must be a large number of RF current loops because the 0V-lines are routed
up and down and around.
Beside trying to achieve a good decoupling I ass
I read in !emc-pstc that Robert Wilson wrote
(in <3FF57405336C9B4C976A1819F860A2560F696F@xng_tirsys.TIRSYS.COM>)
about 'Decoupling - capacitor values', on Wed, 17 Apr 2002:
>The main
>reason is that the ESR of the larger cap begins to rise to unacceptable
>levels as frequency rises (chiefly due t
Capacitors can continue to function quite well above their self
resonance. You should not be worrying about choosing a cap based on self
resonance per se.
However, it is standard practice to parallel a 0,1 uF "bulk" bypass cap
with a much smaller NP0 or C0G type (say 470 pF or 1 nF), especially
In selecting that 820 pF capacitor, check the specifications. The
self-resonance frequency is a function of the capacitor value and the
physical size. Chip caps that are smaller physically will have a have a
self-resonant frequency higher than the same value cap with larger physical
dimensions.
Yes, it makes sense. But the goal here is preventing or reducing Vcc drop
during the time the microprocessor is switching. You need not only low
reactance, but *also* enough capacitance to supply the current needed
_while it is switching_. You have not given enough information here to tell
if 820p
Hello all,
Does anyone know of a decent (by that I mean they work out of something
better than a Quonset hut) vacuum metalizer of plastics in SE Asia,
preferably in Malaysia? There are numerous VM finishers we know of in the
area but none of them apply the coating as a EMC solution, but for cosmeti
A microprocessor is driven by a 12MHz clock. The 5V Vcc-pin is decoupled by
a 100nF capacitor with a few mm leads. We can observe an unwanted 156MHz
signal on the 5V line, maybe 13th harmonic of 12MHz. We will try to
suppress/decouple this 156MHz signal.
Suggestion:
Insert a SMD ceramic capacitor
I've used Acucal in the past Ed. The have several portable labs that
travel around the area at specific times. I think they hit up here in the
Northwest around July. Not a clue when they hit the San Diego area. Here is
their web address. www.acucal.com. They calibrate the equipment at m
Ed,
Use an accredited cal lab. of course, it should be A2LA ;-)
Seriously, they have a list of suitable labs on their website
www.a2la.org
Derek Walton
Hi Listmembers!
I need to get a traceable calibration on my HP-85650A Quasi-Peak Adapter.
The HP service manual calls for use of a Watkins-Johnson Model S1 Pulse
Modulator, which I can't seem to find.
Two questions; for those who do their own in-house calibration, what do you
use? Or, what inde
Martin, my 30+ years experience in Product Safety leads me to believe that
the advantages of a common group/management would outweigh the
disadvantages. First, a H&S department deals with many more issues than you
listed including all worker safety regulations, standards and practices. On
top of t
The Curtis-Straus Update for April, 2002 is now available at:
http://www.conformity-update.com
The headlines are:
Aircraft Interference Sparks FCC Crackdown.
FCC Appointment Becomes A Political Football.
ARRL To Battle Looser RFID Requirements.
Employers Sued Over Alleged Semi Related Birth
I read in !emc-pstc that John Allen wrote
(in <002d01c1e581$5eee4520$0200a8c0@johnallen>) about 'IEC/EN
61010-1:2001 - Dielectric Strength Testing Question ( & another)', on
Tue, 16 Apr 2002:
>Maybe we should wait a day or two to see if anyone else has comments or
>other confirmations, and then I
Sorry for this late answer
At 14:03 11/04/2002 -0700, Gary McInturff wrote:
Can anybody tell me about the 600 mm ETSI footprint - has that
been adopted, is going to be adopted? How adamant is the 300 mm depth, if
neither of the first two questions are no?
Both are adopted
Wh
Greetings,
Our company is considering merging Compliance Engineering with
Environmental Health and Safety.
Compliance engineering is responsible for product safety and EMC as well as
handling product liability issues.
Environmental Health and Safety (EHS) develops and implements chemical
regul
Andy
At least my eyes do not appear to have been deceiving me!
See also John Wood's response (thanks JW) sugguesting that I (we?) contact
IEC TC66
Chairman:
Mr. Cecil CHAPMAN
Grant Instruments (Cambridge) Ltd.
Mill Barn
GB - BASSINGBOURN, CAMBRIDGESHIRE SG8 5PP
UNITED KINGDOM
Tel: +44 1763 247
Gentlemen
Assuming a Win-Tel platform, I have found that both Excel and/or Access to
be adequate for large databases that will not have more than (2) users. The
caveat is that all embedded VBA source be mapped in a separate (formal)
document, and that the Network Admin carefully controls privileg
Et Al:
I am soliciting opinions from anyone who has attempted using an antenna
carousel that aids in doing automated EMI measurements under CISPR 25.
The CISPR 25 specification provides requirements in terms of spacings of
the antenna elements from the walls of the room, size of the room, use
of
Someone recently asked for 100 kV ESD. SInce I work for Schaffner I thought
I'd ask the factory.. Well, hope this helps whoever..
Derek Walton
--- Begin Message ---
I have spoken to John Hardwick at Culham Labs, he says that they can
generate 100kV but he would need much more info before he can o
I read in !emc-pstc that Andrew Wood wrote
(in ) about
'Who decides to sign a D of C', on Fri, 12 Apr 2002:
I declined to respond to this article, but as a result of an e-mail
exchange with Andrew, I will now do so.
>The advice about personal liability was given to me by a professional
>consul
Dear people,
I need to know if the FCC rules (part 15) applied to the following product :
Speaker peripheral connected to a personal computer. This product has its
own power supply. It's connected to the PC via the speaker output.
Reading the Bulletin 62, pages 10 and 12, I'm not sure this devic
> -Original Message-
> From: John Allen [SMTP:ja014d7...@blueyonder.co.uk]
> Sent: 15 April 2002 20:44
> To: EMC-PSTC
> Subject: Re: IEC/EN 61010-1:2001 - Dielectric Strength Testing Question
> ( & another)
>
> Hi Folks
>
> My turn to ask some questions as a newcomer to this v
Can anybody recommend equipment available for hire in the UK, or a UK test
laboratory that facilitates *low energy* (not lightning simulators) ESD air
discharge immunity testing to 100kV?
Thanks in anticipation.
Russell.
---
This message is from the IE
Is there a standard method for measuring AC bonding impedances for
electrical bonding?
Thanks in advance,
Susan Beard
---
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site at: http:
Susan,
I take it to mean that you mearly wanted a 'low impedance' bond which may
(or 'may not' as the case will decide) include a electrical bond from
fasteners like a nut and bolt combo that force two metal surface to contact
under preassure.
The question that arrise from our understanding of t
RE: question on measuring bonding impedanceMike,
A weld occurs when there is melting of metal. The metal will only melt if
it gets enough heat. It will only get enough heat if there is enough of a
resistance there (P=IR), or an arc (where the arc-welder gets its name),
either of which would mean
I read in !emc-pstc that John Allen wrote
(in <006a01c1e4b5$f4967880$0200a8c0@johnallen>) about 'IEC/EN
61010-1:2001 - Dielectric Strength Testing Question ( & another)', on
Mon, 15 Apr 2002:
>My turn to ask some questions as a newcomer to this version of the
> standard:
You may have found
I read in !emc-pstc that Michael Taylor wrote (in
) about
'question on measuring bonding impedance', on Mon, 15 Apr 2002:
> for domestic product safety EN-61010 Sect 6.5.1 requires 25Amps (DC or
>ACrms) or 2x the fuse rating. I have never liked this method of testing.
Well, EN61010 is
I read in !emc-pstc that Robert Wilson wrote
(in <3FF57405336C9B4C976A1819F860A2560F6966@xng_tirsys.TIRSYS.COM>)
about 'question on measuring bonding impedance', on Mon, 15 Apr 2002:
>How about the usual method of determining the value of very low
>resistances and impedances? Pass a known (relati
Susan,
I'm not sure what "AC" means in your message below. I'm
assuming that you mean in the radio frequency range, where low bonding
impedance across joints means good shielding effectiveness.
There is an SAE standard for measuring the "transfer impedance"
across EMI s
Hi Folks
My turn to ask some questions as a newcomer to this version of the standard:
1
Dielectric Strength Testing to Clause 6.8.4 "Voltage tests" & Table 9 "Test
voltages for BASIC INSULATION".
Can anyone confirm my suspicion that there may be a misprint in Column 1
"Clearance" of Table 9 ,
I promised myself I was not going to drag out my soap box and jump into this
but . . .!
(this discussion is limited to only the issue of the measurement of bond
impedance - not if the connection can stand xx amps)
While MIL 5087 establishes some bonding requirements & methods, for
domestic product
I wasn't going to respond to this one because I know of no standard, and I
don't know what you mean by AC, power frequency or rf. But HP/Agilent
makes/used to make a bond meter with a 1 kHz signal. The purpose was partly
to offset the effects of galvanic potentials: an ac measurement cancles the
We use a package called GAGEtrack, produced by the CyberMetrics
Corporation.
www.visit.com
Good if you have a large number of items to track and control. If you
only have a limited number, Excel is a very good tool.
Andrew Carson - Senior Compliance Engineer, Xyratex, UK
Phone: +44 (0)23 9249
How about the usual method of determining the value of very low
resistances and impedances? Pass a known (relatively high) AC current
through the connection, measure the voltage drop and use Ohm's law to
calculate the resistance (and this is, after all, an essentially
resistive connection).
Bob W
Hi Scott:
> In the case of LPS, wouldn't the plastic enclosure still be considered
> "decorative"
> plastic "outside" a fire enclosure and required to meet HB flame class (per
> UL
> 60950, 4.7.3.3)?
Yes.
Virtually all plastic materials meet the HB flame class,
hence my comment that
Mike, we use Excel and include the following data:
Model
Description
Serial number
Manufacturer
Last cal date
Due cal date
Calibration lab
Cal cost
Richard Woods
Sensormatic Electronics
Tyco International
-Original Message-
From: Mike Stone [mailto:mst...@lsr.com]
Sent: Monday, April
Hello Rich,
In the case of LPS, wouldn't the plastic enclosure still be considered
"decorative"
plastic "outside" a fire enclosure and required to meet HB flame class (per UL
60950, 4.7.3.3)?
Regards,
Scott
Rich Nute wrote:
> The choice is yours. If your product is supplied by a
> Limited Po
Good Morning,
I have been looking for a reasonably priced (cheap) software program to
track and produce status reports for our calibrated equipment. Does anyone
have any suggestions? Thank you in advance.
Regards,
Michael Stone
L. S. Compliance Inc.
W66 N220 Commerce Court
Cedarburg, WI 5
Only one I can help with is Puerto Rico. It is currently a Protectorate
of the USA, debating if it shall become a full State or not. So I would
treat it the same as any US state, applying all applicable Federal
regulations and ensuring you meet there interpretations of the NEC with
a suitable NRT
Dear Nick
There are a number of useful links on the draft MID on our website http://www.cherryclough.com";>
www.cherryclough.com under "Useful links to EU directives" (or go directly
to: http://www.cherryclough.com/usefullinks1/index.html";>http://www.cherryclough.com/usefullinks1/index.html).
W
You have been able to get Early Use Letters from UL,
but I think that policy has recently changed a little.
Contact your test engineer.
Regards, Doug McKean
---
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc disc
I have come across some information on the web specifically to do with
electricity and gas meters that infers that a new directive called the
Measuring Instruments Directive is about to come into force.
I have searched the Europa website for information on this but can not find any.
Does anyo
Hi,
Does anyone aware of what this standard JWDS0028 is meant for ?
Where is it originate from ?
Thanks in advance!
Jasmine
---
This message is from the IEEE EMC Society Product Safety
Technical Committee emc-pstc discussion list.
Visit our web site a
All,
Is NRTL marking a mandatory requirement to install a CMTS router in a
cable head end in San Diego?
We have a 48 VDC powered CMTS router which needs to be installed in a
cable operators head end in early May. Although the basic UL
evaluation of the product has been completed without incide
Hi Group,
In a previous life when I developed frequency converters, we used to perform
short circuit tests to UL508C.
I am developing automotive ESA's which may find use in non-automotive
applications ( Mains - DC power source ).
Is output short circuit testing covered by some generic standa
Hi Jim,
As the function of the Emission standard is to protect the
spectrum, it cannot be seen different then "protecting the spectrum
of the environment the equipment is used in" (office).
(seen the physical range any interfence can go: +/- 30 meters)
Then seek appropriate standards, taking acc
Hi all,
The Automotive directive 95/54/EC becomes mandatory October 1 2002. Is there
a web-site which lists the notified / certification bodies within EU for
this directive?
Thanks.
Best regards
Amund Westin, Oslo/ Norway
---
This message is from the I
You're already on the edge of the code with this one. You describe the
equipment as permanently installed. Under those circumstances you
normally could not use flexible cords. You might use the condition
"400.7 (6) Connection of utilization equipment to facilitate frequent
interchange" to permit th
I am posting the following for Dan Modi ( dan.m...@alconlabs.com ). Please
contact him direct. Do not forget to mark the 2002 IEEE EMC Symposium on your
calander to attend and by all means do not miss the Product Safety Workshop (or
the other TC-8 Sessions). Rich Nute is willing to provide co
George, the standard fails to describe the allowed sizes of openings in the
top and sides of a fire enclosure. As far as the standard is concerned, fire
must only go down since only bottom openings are described. The side and top
openings that are described are for electical enclosures and do not
Dear Volker Gasse
Is this a pure Electrical Safety book or does it also include EMC ?
Best regards
Amund
-Opprinnelig melding-
Fra: owner-emc-p...@majordomo.ieee.org
[mailto:owner-emc-p...@majordomo.ieee.org]På vegne av Volker Gasse
Sendt: 8. april 2002 09:52
Til: geor...@lexmark.com
K
Hello Group,
I am considering a strategy for shipment of individual circuit packs
into the EU. These circuit packs are part of an overall (rack mountable
shelf) custom ITE system which will be evaluated to the appropriate
requirements/directives (LVD and EMC) and will have a CE marking. I
envis
Hi Oscar,
Please be advised that the IEC has replaced IEC60950 3rd Ed. with
IEC60950-1:2001. Excerpted, the
foreward of IEC60950-1 states "This first edition of IEC 60950-1 cancels and
replaces the third
edition of IEC 60950, issued in 1999, and constitutes a technical revision.".
The countri
If this is what you feel in necessary at moderate frequencies (I believe
the original discussion was related to 600 MHz), I'd hate to see what
you might feel is required at high frequency. :)
The idea of "chip in board" that you mention is not new. It was first
tried in the Far East some years ag
Cortland Richmond <72146@compuserve.com> wrote:
> Current flowing through a via or a capacitor creates a voltage drop
>which drives the planes it connects, as a radiator. A good antenna
>may be made out of planes connected by a via, with RF applied
>between them. We need to avoid doing this
Chris, what standards did the keyboard and mouse manufacturer(s) test to?
Try contacting the manufacturer directly and requesting the full EMC test
report, including the ESD test setup. Sometimes this is a real pain in the
tail to get hold of for such low dollar equipment, but it sounds like you
Clearly, we need to ensure that lighting carries the appropriate
regulatory warnings! A couple of paragraphs of the usual rambling UL/CSA
warnings and cautions should do the trick. :)
Bob Wilson
TIR Systems Ltd.
Vancouver.
-Original Message-
From: geor...@lexmark.com [mailto:geor...@lex
Well, maybe.
I think you mean the word spelled "fey."
Also from the Encarta World English Dictionary:
fey 1.
(omitted)
2. SUPERNATURAL - relating to or typical of magic or the supernatural
3. CLAIRVOYANT - supposedly able to see into the future
4. SCOTLAND - DOOMED TO DIE [Old English faege,
Yeah, blame John! :)
For what it's worth, in the 25 years I have been involved in the
mechanical packaging design of electronic enclosures, I have never heard
of the word "faying". One can't help but wonder if someone just
misspelled "facing".
Bob Wilson
TIR Systems Ltd.
Vancouver.
-Origina
Bob,
before you go round the houses on this, I suggest you talk to Trace at A2LA.
He can tell you what a lab should really be doing IMHO, a spreadsheet is
all you really need.
tmcintu...@a2la.org
Best regards,
Derek Walton
Greeting fellow vocabularians,
The root word, 'fay" is ancient Scottish, meaning to have the power of
prediction. Those of you that are fay may have seen this coming.
I wonder if anticipating grounding is similar to expecting volts.
Regards,
Alan Brewster
Senior Systems Safety Engineer
Does anyone know of any measurement uncertainty software that may be on the
market to
help in the determination of measurement uncertainty for the various EMC
test methods?
Thanks,
Bob Heller
3M Product Safety, 76-1-01
St. Paul, MN 55107-1208
Tel: 651- 778-6336
Fax: 651-778-6252
-
The Encarta World English Dictionary says:
Fay to join pieces of wood together tightly, or fit tightly inside
another piece of wood.
Do note this is a hard-cover dictionary, NOT an online one. I have not
(yet) looked online.
Cortland
---
This messag
Ed,
Thank you. Especially the part blaming Woodgate.
My grandfather's name was Fay (son of Irish immigrant) and I always wondered
at the origin of that name.
- Robert -
Robert A. Macy, PEm...@california.com
408 286 3985 fx 408 297 9121
A couple of weeks ago, there was a thread discussing bonding techniques for
ground studs. I suggested that MIL-B-5087 had some nice drawings showing
typical accepted military practices. Of course, MIL-B-5087 has been
superseded by MIL-STD-464, but you can still find electronic copies of
MIL-B-5087
Hi group
Can anyone tell me offhand whether the surge test requirement for Australia is to IEC 1000-4-5 which uses a network with a 1 uF source capacitor or is it similar to the FCC test which I believe uses a 20 uF capacitor.
Best Regards
John CroninJoin the worlds largest e-mail service with
1) Correct, this cannot be used in a multiwire branch circuit since it
may eventually be removed without being bypassed. The concern is that an
open neutral in a multiwire (e.g. 120/240 3w or 120/208 4w) circuit
leaves loads connected in series phase to phase. The voltage across a
product intended
I'm no medical Guru either but I know the sort of field levels involved.
They range from about .5 to 3 teslas. This is not much higher
than the fields in the gaps of electrical motors and generators
(up to 1.8T in normal silicon iron and up to 2.1 T in cobalt
iron used in aerospace machines) Th
We are facing the same challenge.
The way we address it is essentially the TCF route, including a Competent
Body involvement.
Our installation contains some equipment qualified for residential
environment only, which wouldn't meet the industrial immunity test levels by
itself. We add filters in th
I would amplify on my original MOTO response and say that it is common
practice to scan using peak detection, and use average detection only at
frequencies where an outage condition occurs; that will drastically reduce
test time.
--
>From: "Gert Gremmen"
>To: "Ken Javor" , "Gordon,Ian"
At ce-test, we call this kind of answer EOE - Evidence by Experience,
in addition to MOTO, the dwell time should extend any slow variations
that EUT emission contains
A fine and obvious example is the Microwave oven: emission varies
substantially with the rotation degree of the food rotating p
I read in !emc-pstc that Robert Wilson wrote
(in <3FF57405336C9B4C976A1819F860A2560F698D@xng_tirsys.TIRSYS.COM>)
about 'Power Factor regulations.', on Tue, 30 Apr 2002:
>We will be starting the design of a relatively simple, off-line
>switchmode power supply that will be used to power an LED Lum
I read in !emc-pstc that richwo...@tycoint.com wrote (in <846BF526A205F8
4BA2B6045BBF7E9A6A01F140FA@flbocexu05>) about 'General Product Safety
Directive', on Tue, 30 Apr 2002:
>Now, back to the original question. I found the following definition of
>professional apparatus in EN 55103-2 (immunity
I have a general question regarding power factor limits relating to the
design of off-line switchmode power supplies.
We will be starting the design of a relatively simple, off-line
switchmode power supply that will be used to power an LED Luminaire (for
lighting up the outside of buildings). A p
I have a couple of questions regrading the National Electrical Code:
1) Consider a power measuring device that is intended to be installed into
a residential 120V branch circuit, protected by a single 15 A or 20 A
circuit breaker. The device would be installed into a conduit outlet box
on th
Well, this series sure took a left turn and accelerated hurriedly out of
site of the original intent which was to determine what the term "consumer"
means as used in the GPSD. The imaginary product example I put forth was
intended solely to support the question, and I in no way advocated that such
You have me all confused here. You claim the equipment should be able
to state heavy industrial immunity but at the same time acknowledge that some
of the components don't meet the surge requirements. Kind of like the
government saying fiscal responsibility - an oxymoron.
If the
Hi Amund,
I read your email (below). I'm no medical device expert; but I'm
wondering if the magnetic strength limit was set so high due to MRI
(Magnetic Resnonance Imaging) devices. My understanding is that MRI
devices produce HUGE magnetic field levels. According to a recent
newspaper story t
How do the safety standards (for example, IEC 60950 and their clones) define
'insulating tape'?
Are the insulating properties determined as applied in the end product by hipot
and leakage current?
On Mon, 29 Apr 2002 12:16:16 -0700 (PDT), Rich Nute wrote:
>Thanks for sharing your findings on ins
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