Re this: If the power supply is for a single unit utilizing a common power
bus for the power supply input, then the output ripple of the supply might
need to be controlled more stringently, perhaps on the order of tens of
millivolts.
Huh? Maybe I've been in Alabama too long, but I don't
Maybe I've been working on space systems too long...you can draw your own
conclusions about that. At any rate, even though it isn't likely to be what
Derek was after in the first place, let me try to make my statement clearer:
What I was referring to was the distinction between a power
To All:
I was wondering if there is anybody out there who is interested in buying
any ISDN based access switch for Video, Data, Voice call routing and
networking equipment. We do have a fine products and a variety of models for
Basic Rate Access and Primary Rate Access/T1/E1 networking for video
Hi Ed.
You would need to be a pedantic purist to project a steel ball
through an arc, 'pendulum like' and strike a verticle surface with
the necessary impact required in ***950 by electromagnetic trickery.
There is an addition to the drop test in the standard for vertical
surfaces. the
I should not have required my old (non CE marked) brain to recall
something over one day old! It is halon, not halogen, that we use
in our old (1972?) EMC chamber. I believe that halon is far less
a toxic threat than halogen, which is the family of agents which
includes chlorine etc.
Halon is
Hello Group,
In EN61010, section 6.3 says, If the voltage exceeds the value listed in
6.3.1 or 6.3.2, the current and capacitance shall be measured.
I understand how to measure current (6.3.1.2) with the circuit in Annex A, but
how do I measure Capacitance for section 6.3.1.3? It doesn't
I should have been referring to Halon, not Halogen. Must have been in that
CE marked brain clamp too long last night.
Scott
s_doug...@ecrm.com
ECRM Incorporated
Tewksbury, MA USA
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Scott,
I beg to disagree, ... but, Halon, along with Freon and other compounds was
banned by the Montreal Protocol, ostensibly to protect the ozone layer.
Interestingly, the Freon replacements must, per the treaty, be phased out in
20 years - by coincidence about the time when the international
Peter:
I don't think a 250Vac fuse can be relied on at 250Vdc, let alone
370Vdc.
Regards,
Jim Eichner
Senior Regulatory Compliance Engineer
Statpower Technologies Corporation
jeich...@statpower.com
http://www.statpower.com
phone:(604) 420-4820 ext. 2162
fax: (604) 420-1591
Any
Colleagues,
I am curious to know how you handle PWB design for safety compliance:
1. How do you document the required spacings on the schematics?
2. Do you use tools provided by your schematic entry system (ViewLogic,
Valid or whatever) to enter these requirements?
3. Does
Posted for: lothar.schm...@cetecom.de
-Original Message-
From: Schmidt Lothar, Essen [SMTP:lothar.schm...@cetecom.de]
Sent: Wednesday, November 17, 1999 7:33 AM
To: 'ken.ja...@emccompliance.com'
Cc: 'emc-p...@ieee.org'
Subject: AW: Shielded Enclosure Fire Hazard
We are trying to determine the proper fusing for the UK power cord. The
products we will be using the cord set on will never exceed 3amps in normal
operating conditions.
For the power cord set the Manufacturer has provided us with the following
information:
BSI/ASTA Approved
British Male to
BE CAREFUL ! ! ! If this PS does not have Power Factor Correction
Many switching power supplies comply with the conducted emissions limits
BECAUSE of the conducting angle of the AC diodes.
Simply said, the AC rectifying diodes only come on for 15--18% of the duty
cycle. therefore the noise
I need help on power cords for South America.
We are supplying our US customer with product that he mostly uses in
the US. He will however be shipping a few hundred to various South
American countries.
The power cord which we have packed with the units, has an IEC
connector on one end, and a
George,
I once worked in a laboratory that developed the Doppler weather radar we
all see on TV today. In our just built (in 1979) control room, they put a
halogen extinguisher system. Halogen works by displacing the oxygen and thus
the fuel for the fire. No fuel, no fire. The system could fill
All,
Some time back, one the contributors to this forum had a one page
table listing countries and what compliances were mandatory for these
countries. I seem to remember it was an attachment to an email
rather than a web link. I have not been able to find it in
rcic.com. Can someone help me
Peter,
Is the DC Input shown on the power supply ratings label along with the AC
Input? If this is the case then both inputs would have been tested when the
supply was tested by UL and TUV for Recognition. No additional testing would
be required. We have used supplies that are rated for both an
Derek
The most common method I've found effective - even after sale- is the use of
a toroidal ferrite core , large enough to take 8-9 turns of the power cord,
mounted as close to the supply as possible. There is 15-20 dB decoupling to
common mode noise provided by this method and I've used it
Probably the wrong words to use.
I should have said design in a highly reliable GFI function to detect when
an installation has been done improperly. That, coupled with incredibly
clear installation instructions should cover legal liability (and moral
liability - after all what more can one do,
Raymond
I think you have asked a very big question - and unfortunately I do not
have time to go into it!
However, I also think that it has been discussed before in EMC-PSTC, and so
I suggest that you ask Ed Price or Rich Nute if they can identify the
previous threads for you to examine on
Hi,
I just bought a 2 ball bearing from Whistler Bearing Company in Denver for
$15.00.
Thats fifteen, not one hundred and fifty. However, I will be happy to charge
you a mere $75, to purchase it for any of you and mail it to you. :)
Mat Aschenberg
-Original Message-
From: Dwight
I don't normally go around dropping steel balls on things, but if I wanted
to be a purist about it, I would hold the ball by an electromagnet, so I
wouldn't have to alter the shape and mass of the ball by drilling or
affixing an eyelet. It also sounds like more fun.
Ed
Derek
In my experience in the aerospace industry, the output voltage ripple is
typically specified. However, the amount of acceptable ripple and the frequency
range of concern depends on the application. An example is the ripple level
specified by MIL-STD-1541A which calls for a ripple limit
Laura,
Also I am interested to know if a detachable UK power Cord is required to be
fused.
J.R.: YES. The fuse must conform to BS 1362.
Products using this line cord have integral fuses in both AC lines.
J.R.: Just one fuse. It is located in the BS 1363 style power plug and wired to
the
I've been told by a source in France that EN 50082-1 and
EN 50082-2 Industrial level generic standards are going
to be combined into this IEC 61000-6 series of standards.
I'm also told that this series will become EN, replace the
generic industrial standards, and become effective
January 1,
Laura,
For UK power cord sets, BS 1363 and 1362 are the two standards you want to look
at for plugs and fusing, respectively. You have to fuse the plug regardless if
your product is double fused.
Regards,
Ron Wellman
ron_well...@agilent.com
-Original Message-
From: Non-HP-LNewton
We use them in the secondary to provide limited power outputs per IEC 950.
We have obtained UL and TUV certifications without a problem.
Richard Woods
--
From: pmerguer...@itl.co.il [SMTP:pmerguer...@itl.co.il]
Sent: Wednesday, November 17, 1999 8:43 AM
John,
I am very insterested in your explaination on fused plug requirement
between the ring main supply system and branch or spur systems. Could you
please shed more light on to me about the fused plug requirement on the
ring main supply and a simply way to identify the said main supplies.
Dear Folks,
I have a product with an UL/TUV UL1950/EN 60 950 Approved 100-240 Vac rated
switching power supply. Manufacturer has means for 110-370 Vdc connection
to this power supply. My question is can this be done without additional
tests? If tests are necessary, what kind of tests are
Between a hard place and a rock
It is hard to argue that EMC chambers should not have fire protection.
The newer tiled facilities may have little combustible content other than
the DUT. However, most factory insurance carriers will insist on an
adequate prevention and extinguishing
Hello,
Put the sprinklers in. Also, make sure they are 360 deg (i.e. spray up and
down) heads!!.
At a previous employer, we had a fire in a cone lined, shield room. We had
sprinklers, but they were only 180 deg. (i.e. down). The fire started when
some cones on the ceiling came loose and
Hello Group,
Anyone had problems with Test Houses regarding the use of PTCs in
Transformer Primary and/or Secondary Windings to Protect Against
Overload/Short Circuit Conditions?
Regards,
+++
RTTE Directive Seminar
Renaissance Hotel, Tel-Aviv
12th January 2000.
Another slant on this issue is the price of the product. The FCC looks
at the function, price and marketing of an ITE product. The maker can
claim it is intended for commercial enterprises, and should be Class
A. However, if it is affordable for the typical consumer PC workstation,
OR is
Hi John
When I typed that last statement I didn't believe it to be naive but
obviously it was. I was surprised to find that quite a lot of countries use
UK type plugs (see web sites below). Amongst them is Hong Kong although I
believe that Hong Kong requires plugs to conform to BS1363.
We also had to install sprinklers.
Richard Woods
--
From: Ken Javor [SMTP:ken.ja...@emccompliance.com]
Sent: Wednesday, November 17, 1999 1:37 AM
To: Price, Ed; 'emc-p...@ieee.org'
Subject: Re: Shielded Enclosure Fire Hazard
This
I don't know where you got the information for commercial applications.
0-70C are the specs for commercial grade ICs. There is no standard for
commercial equipment. However, generally, ITE intended for indoor use is
rated 0-35C. For non-air conditioned space the upper limit goes to 55C.
Laura
With respect to the last line of Chris Colgan's email: Be careful!
In the UK we have seen a number of bogus power cords with 13A plugs which
have no provision for fuses.
Additionally, they are much narrower than BS1363-compliant plugs and have
no insulating sleeving on the Line
There is a further issue because the generic emissions standard EN 50081-1
covers the Residential, Commercial and Light Industrial environment, i.e. the
only one it does not cover is the real industrial (EN 50081-2). This means that
all normal commercial applications require EN 50081-1 which
Hi Mike
Don't panic! The test level is not as high as it seems. For a start, the
test level of 3V is the open circuit generator output. Next, I guess that
you could reasonably expect high interference levels in the 150kHz - 80MHz
range after all, amongst other things, CB radio, taxi comms and
Laura
Re. the power cord.
SI No.1768 requires UK consumer products to be fitted with a plug conforming
to BS1363. Both BS1363 and SI 1768 require the plug to be fused.
The fuse value is determined by the cross sectional area of the power cord
conductors.
I doubt that you could find an
In the BSI catalogue I have found : -
BS EN 1264 Floor Heating. Systems and Components
comprises :
BS EN 1264-1:1998 Definitions and symbols
BS EN 1264-2:1998 Determination of the thermal output
BS EN 1264-3: 1998 Dimensioning
All the above BS are identical to the EN.
There is also a BSI CP 1018
Laura
All UK standard power cords require to be fused - regardless of the fusing
in appliance to which they are connected - because we use a totally
different building ring main supply system to most other countries which
use branch or spur systems !
The main reason is that the power cord
Not a recommendation - I just saw the ad in Compliance Engineering - but
non-combustible pyramid absorbers are offered by the German company Frankonia.
See: www.frankonia-emc.com
Roger
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To cancel your subscription, send mail
Robert,
I don't think GFIs are failsafe. Don't they all come with test buttons?
Matt
Why has no one mentioned using a GFI detector as a failsafe way to make
certain the installation is done per spec?
After all, in the US the manufacturer still comes out liable for any
damages.
I'm not sure if the question is technical or spec-ese. I don't know the
spec-ese answer, but technically the answer is straight-forward. If the
anticipated loads are not antenna-connected receivers, then the only CE
concern is that the output wires not radiate sufficiently to cause rfi. You
This happened to me at a previous employer. There is some sense to it in
that foam absorber is quite flammable, even with modern precautions and
flammability requirements. We had to install sprinklers. The system was set
up so that the sprinklers are dry until a smoke alarm signal allows
My lab just had an annual inspection visit by our friendly fire hazard
inspector. Seems that after 4 successive years of inspections, I suddenly
failed this year.
Hi Ed,
Don't shoot the bearer. Go find the guy who passed you the last 3 years -
shoot him.
If it's the same guy - well it's
Hi Laura:
Could someone please tell me where previous EMC and safety discussions are
posted on the internet.
emc-pstc messages are archived at:
http://www.rcic.com/
Click on Virual Conference Hall. The archives can
be searched by topic.
Also I am interested to know if a
BTW, you may find a 50mm diameter ball bearing, but will it weigh 500g
+/-25g? And then you'l have to drill and tap it for an eyelet for the
string.
The impact ball spec was written around a 2-inch diameter
ball bearing.
Drilling and tapping the ball bearing requires some sort
of
HI,
would anyone like to suggest a specification for controlling conducted
emissions from the output of a power supply or battery charger. The
market place is either the USA or Europe.
Thanks,
Derek.
--
Derek Walton
Owner
L. F. Research EMC Design and Test Facility
12790 Route 76,
Poplar
Hi Listmembers!
My lab just had an annual inspection visit by our friendly fire hazard
inspector. Seems that after 4 successive years of inspections, I suddenly
failed this year. The reason is that my 24' x 35' x 10' modular shielded
enclosure doesn't have internal water sprinklers.
Now I'm all
Posted for: mmur...@alesis1.corpusa.com
:-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-):-)
Ed Price
ed.pr...@cubic.com
Electromagnetic Compatibility Lab
Cubic Defense Systems
San Diego, CA. USA
619-505-2780 (Voice)
619-505-1502 (Fax)
Military Avionics EMC
Joe,
The 2nd Edition of IEC 61010-1 is brand new. The amendments you speak of were
for the 1st Edition. The big question is whether CENELEC will adopt the 2nd
Edition without modifications.
Regards,
+=+
|Ronald R. Wellman
Hi Joe,
According to ISO7000, symbol 0659's description is Biological risks.
I hope this helps.
Best regards,
Ron Pickard
rpick...@hypercom.com
MartinJP@pebi
Could someone please tell me where previous EMC and safety discussions are
posted on the internet.
Also I am interested to know if a detachable UK power Cord is required to be
fused. Products using this line cord have integral fuses in both AC lines.
You help would be greatly appreciated.
-Laura
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