The terms are international, not just EU.
If you look in the IEC Electropedia terms and definitions there is
en
high voltage
high tension
HV
voltage having a value above a conventionally adopted limit
Note – An example is the set of upper voltage values used in bulk power
systems.
[SOUR
The correct reference for
IEC 61643-331:2017 is "from 8.2.2 of IEC 61643-331, Figure 4." Thinking
about what John said, it seems to me the quickest way of fixing the IEC
62368-1:2018 reference, without invoking TC 108, would be for SC 37B to
issue a clause 8 corrigendum.
Regar
ed an interesting test circuit that imposes a common-mode
surge on both supply polarities. Any system polarity earthing and the
presence of any voltage limiting functions condition the resultant surge
on the system to be common-mode, differential mode or a mixture of both.
Regards,
Mick Maytum
https://ict-surge-protection-essays.co.uk/
-- Original Message --
From: "Pete Perkins"
To: "Mick Maytum" ; EMC-PSTC@listserv.ieee.org
Sent: 13/03/2019 06:11:38
Subject: RE: [PSES] classification of the output
Mick, Thanx for the reply given on this thread.
Joe Randolph and I talked about “pulsed power” delivery at the 2019
ATIS-PEG conference last week and how it should be treated.
A good starting point is the IEC 60479 series of documents on “Effects
of current on human beings and livestock”. IEC 62368-1 mentions the time
locked IEC TS 60479-1:
disconnect, gets to the heart of
the matter. But, as far as I'm aware, none of these tests apply a surge
voltage to check for open thermal switch arc over.
Regards,
Mick Maytum
Safety and Telecom
Standards
mjmay...@gmail.com
https://ictsp-essays
gards,
Mick Maytum
Safety and Telecom
Standards
mjmay...@gmail.com
www.ictsp-essays.info
-- Original Message --
From: "Joe Randolph"
To: EMC-PSTC@listserv.ieee.org
Sent: 31/10/2017 02:09:14
Subject: [PSES] Regulatory requirements for MOVs placed line-to-ground
on AC mains port
.
Regards,
Mick Maytum
-- Original Message --
From: "Brian O'Connell"
To: EMC-PSTC@listserv.ieee.org
Sent: 06/04/2017 22:00:35
Subject: Re: [PSES] EU Certifications Required for Surge PRotectors?
Dunno, as have just used the standards referenced in annex G of
62368-1, or wha
On 26-Oct-15 6:29 PM, Scott Aldous wrote:
_Table 5 (Capacitor Energy)_
For the energy from a capacitor, the table takes into account
capacitance and voltage, so both need to be taken into account since
the equation for available energy from a capacitor includes both
variables. This is similar
Peter,
The metrics we use to specify the more complex surge waveshapes are
only a modest improvement over the answer "a red one" to the "what car
do you drive?" question.
The ring and possibly 8/20 (part of the combination) waveshapes
have current reversals, which complicates matters. W
. That would perhaps eliminate
the need for the subscription since that's primarily what we need the symbols
for anyway.
Thanks
-Dave
-----Original Message-
From: Mick Maytum [mailto:mjmay...@gmail.com]
Sent: Saturday, January 17, 2015 5:26 PM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Cc:
David,
I am familiar with IEEE Std 315, IEEE Std 315A
(supplement) and the IEC 60617 database.
The 315 was created in 1975 and the 315A in 1986. These
documents show some symbols with an over and under lined
"IEC" label. At the time of creation the IEC reference was
to the symbols in I
Each Annex is terminated by a short horizontal line. The
"thin line" is meant to be there, but it is not part of the
symbol.
Mick
On 24/09/2014 20:31, Brian Oconnell wrote:
Am confused over this. Cannot determine if thin line is a PDF 'artifact', or if
that is the new image for the EEE mark. T
Joe,
My memories of the early 13 A plugs in the UK is their
consistency rather than inconsistency. I was in TV design at
that time. Traditionally the early TV power supplies used a
half-wave rectifier, so the chassis was either L or N. When
the 13 A plug became widely used the chassis was
Rich,
Given your rational that surge protective components
(SPCs), such as MOVs or GDTs, can have a fault mode anywhere
between a short-circuit and an open-circuit, looks like
there is a disconnect in the test levels.
In the open-circuit situation, the SPC does not divert
current and t
John,
It is true that people used to worry about GDTs
venting. In venting the GDT sparkover voltage greatly
increased. In fact, there was a US trend to include a
Back-Up (air) Gap (BUG) across the GDT component in case
this happens. In fact, due to contamination, these BUGs were
more unre
Kris,
If you pull a copy of "Impulse generators for testing
low voltage equipment" from the IEEE PES Surge Protective
Devices Committee (SPDC) Website.
http://pes-spdc.org/sites/default/files/Impulse_generatorsaddedrev2.pdf
Figure 12 of the document shows the typical 1.2/50-8/20
comb
p we should use this the
8 mS / 10 mS rating. That's mS, not uS.
--
Thanks, -doug
Douglas E Powell
doug...@gmail.com <mailto:doug...@gmail.com>
http://www.linkedin.com/in/dougp01
On Thu, May 10, 2012 at 6:58 AM, Mick Maytum
mailto:m.j.may...@ieee.org>> wrote:
Doug,
Doug,
My previous message gave the IEC rulings - terms
clamping voltage and nominal varistor voltage - for two
specific points on the MOV clamping (clipping) characteristic.
For completeness IEC 61010-1, ed. 3.0 (2010-06) defines the
following:
*working voltage *
highest r.m.s. value o
Clamping voltage is the MOV voltage under specified surge
conditions. Typically that will be an 8/20 impulse.
IEC 61643-331, ed. 1.0 (2003-05)
clamping voltage VC
peak voltage across the MOV measured under conditions of a
specified peak pulse current (IP) and specified waveform
Your 1 mA volt
Dans experience reminded me of a guy who bought a 120 V
coffee maker as a present for someone in (old) England.
Having some knowledge of AC supplies he bought a 240 V to
120 V travel adaptor so the coffee maker could operate on UK
240 V mains. Unfortunately the adaptor consisted of a series
re
the data as HTML expressions in an Excel
spreadsheet - a frustrating exercise if you were not
proficient in HTML.
Mick
On 12/01/2012 11:24, John Woodgate wrote:
In message <4f0eba2a.8070...@ieee.org>, dated Thu, 12 Jan
2012, Mick Maytum writes:
Nice to see a harmonised approach fr
The IEC offers several definitions of thermal equilibrium in
its Glossary.
thermal equilibrium conditions
stable temperature conditions indicated by temperature
changes of no more than 3 K (5 °F) or 1 % of the absolute
operating temperature, whichever is higher between two
readings 15 min apa
Brian,
I find portions of our discussion has been transcribed
to the entire IEC TC 108 group. Thus I feel I should respond
to your TC 108 comments
A problem NOT ADDRESSED by TC108 is the increased energy AFTER a surge, or
during a SFC, due to the 120% rating requirement. Perhaps this was
her standard, I wonder?
Ralph McDiarmid | Schneider Electric | Renewable Energies Business |
CANADA | Regulatory Compliance Engineering
From: John Woodgate
To:EMC-PSTC@LISTSERV.IEEE.ORG
Date: 11/11/2011 06:48 AM
Subject: Re: [PSES] MOV requirements
In message<4ebd2d05.5050...@ieee.org>, dated
2011, Mick
Maytum writes:
>MOV, Varistor, VDR; Metal-Oxide Varistor are all names for a
>voltage-limiting component using a particular technology.
I think this 'particular technology' is an important
point. As I
understand it, devices like Transorbs (TM?) are quite
diff
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