Hi Neil:
> All I get on visiting the site is "404 Page not found error" on their
> home page. Access to all other pages seems to be ok. Using their search
> engine facility does not seem to find anything with respect to
> application notes or harmonics. Anyone else have this probl
With reference to the Fluke Application Note suggested by Rich and
commented on by John.
All I get on visiting the site is "404 Page not found error" on their
home page. Access to all other pages seems to be ok. Using their search
engine facility does not seem to find anything with respect to
I read in !emc-pstc that Rich Nute wrote (in
<200301311805.kaa24...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Fri, 31 Jan 2003:
>
>
>
>Hi John:
>
>
>> >Yes, delta-wye distribution transformer overheating
>> >does occur due to t
I read in !emc-pstc that Rich Nute wrote (in
<200301311957.laa25...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Fri, 31 Jan 2003:
>Fluke has a good explanation of the deleterious
>effects of harmonics. See:
>
>http://www.fluke.com/ElectricPower/elec.asp
Hi John:
> Thank you for that and the rest of the information, which could prove to
> be very helpful indeed. I would like to use it in my continuing efforts
> to defuse the arguments between the former TC74 experts in TC108 and the
> SC77A/WG1 people. May I say that the information c
Hi John:
> >Yes, delta-wye distribution transformer overheating
> >does occur due to the circulation and dissipation of
> >the triplen harmonics in the primary (delta) winding.
>
> Thank you for that and the rest of the information, which could prove to
> be very helpful indeed
I read in !emc-pstc that Rich Nute wrote (in
<200301292324.paa09...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Wed, 29 Jan 2003:
>Yes, delta-wye distribution transformer overheating
>does occur due to the circulation and dissipation of
>the triplen harmon
I read in !emc-pstc that Rich Nute wrote (in
<200301301638.iaa15...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Thu, 30 Jan 2003:
>As Ken Javor described, in the USA, voltage
>distortion is largely a local (privately-owned
>wiring) premises problem due to "
I read in !emc-pstc that Ken Javor wrote
(in <0h9j008afer...@mtaout03.icomcast.net>) about 'Unity Power Factor'
on Thu, 30 Jan 2003:
>Yes I am in the US so clearly I must have been mistaken. Seriously, when
>that business started in 1989 there were relatively few PCs in
PC running all day
long. It would have been interesting, in retrospect, to have taken line
voltage oscillographs at representative locations as the PC density
increased.
>From: John Woodgate
>To: emc-p...@majordomo.ieee.org
>Subject: Re: Unity Power Factor
>Date: Wed, Jan 29, 200
Hi John:
> Aren't you in the USA? If so, you must have imagined the peak-
> flattening. I am assured by the US experts on SC77A/WG1 that this
> phenomenon is unknown in USA, and the only effect of IEC/EN 61000-3-2 is
> that it increases the prices of PCs dramatically and keeps US prod
I read in !emc-pstc that Ken Javor wrote
(in <0h9h00l4ovp...@mtaout02.icomcast.net>) about 'Unity Power Factor'
on Wed, 29 Jan 2003:
>I noticed this several years ago at
>the office building I worked in at the time. My cube moved from one end of
>the building to
Hi John:
> >The only other problem that I know of is distribution
> >transformer overheating. But, I believe such
> >transformers are very much larger than 3 kVA, so 3 kVA
> >of non-linear loads would have very little effect.
> >
> I mean *concentrations* of loads, individuall
in breaker
at the two different cubes. This is a power/crest factor issue, not
directly a harmonic issue, although drawing current only near the peak of
the waveform will definitely generate harmonics.
>From: John Woodgate
>To: emc-p...@majordomo.ieee.org
>Subject: Re: Unity Power Factor
I read in !emc-pstc that Rich Nute wrote (in
<200301291623.iaa07...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Wed, 29 Jan 2003:
>
>
>
>Hi John:
>
>
>> >In the USA, this has largely been fixed by a change in
>> >the USA National
Hi John:
> >In the USA, this has largely been fixed by a change in
> >the USA National Electrical Code.
>
> There must be quite a number of installations that are not yet upgraded.
Where a problem existed, it was fixed by pulling
another neutral.
> Are there any other problems
I read in !emc-pstc that Rich Nute wrote (in
<200301281747.jaa29...@epgc264.sdd.hp.com>) about 'Unity Power Factor'
on Tue, 28 Jan 2003:
>
>
>
>
>Hi John:
>
>
>> >No, this is not much of an issue for the U.S. (unless your facilit
Hi John:
> >No, this is not much of an issue for the U.S. (unless your facility
is
> >actually affecting the utility);
>
> ... or frying the neutral conductors with third-harmonic current.
In the USA, this has largely been fixed by a change in
the USA National Electrical Co
I read in !emc-pstc that boconn...@t-yuden.com wrote (in ) about 'Unity Power Factor'
on Mon, 27 Jan 2003:
>No, this is not much of an issue for the U.S. (unless your facility is
>actually affecting the utility);
... or frying the neutral conductors with third-harmonic c
I read in !emc-pstc that don_macart...@selinc.com wrote (in ) about 'Unity Power Factor' on
Mon, 27 Jan 2003:
>Why are so many U.S. manufacturers using Unity Power Factor correctors in
>low wattage power supplies?
>
>Are there any U.S. requirements for Harmonics or they j
he surface of earth, so PFC has to be part
of the design.
Brian
-Original Message-
From: don_macart...@selinc.com [ mailto:don_macart...@selinc.com]
Sent: Monday, January 27, 2003 9:48 AM
To: emc-p...@ieee.org
Subject: Unity Power Factor
Why are so many U.S. manufacturers using Unity
Why are so many U.S. manufacturers using Unity Power Factor correctors in
low wattage power supplies?
Are there any U.S. requirements for Harmonics or they just trying to meet
CE mark requirements (devices rated > 75W)?
Regards,
Don
This message is from the IEEE EMC Society Product Saf
22 matches
Mail list logo