Quick power supply question

Does it mean "DC" or "DC and pulsating DC?"

It seems like the solid line denotes filtered DC and the dotted line denotes rectified (and unfiltered) DC. (I may be wrong...)

It denotes DC but doesn't indicate anything about regulation.

I read in sci.electronics.design that markzoom wrote (in ) about 'Quick power supply question', on Sun, 9 Jan 2005:

Officially, it just means 'DC'. People seem to think they can allocate new meanings to these IEC 60417 symbols and everyone will be informed of the changed meanings by telepathy.

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Hmm, I didn't intend to redefine anything... that's just what sounded the most logical. Most DC devices WILL work on pulsating DC... it's an observation.

Perhaps it isn't that people are intentionally redefining standards, just that our logic is changing faster than our technology.

LOL

This guy should have been notified by prophetic telepathy that this same topic would come up in the recent past and at that time you would answer a question he wouldn't think of asking until a future date :)

I wouldn't have expected this same topic to come up again so soon. Amusing.

--
Best Regards,
Mike

DC is DC and not pulses, sorry. I'd expect some AC components, perhaps 100Hz wise and definitely switcher noise. Both perhaps in the sub volt region.

Rene

--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

This is what I meant by my comment about people redefining the symbols. I'm not saying that Mark Jones is trying to do that, but it has been done. Dotted over solid is alleged to be unregulated and solid over dotted is alleged to be regulated. NOT according to IEC 60417.

If people want to redefine the symbols, the secretary of IEC SC3C would be pleased to hear from them. Contact via the web site

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

LOL. Yes, the dotted line should be below the solid one unless you're in Oz....

I wish the people who dreamt up all these marvellous standards would include a symbol that tells you if a supply is regulated or not without taking it apart. I just bought a batch of 10 used 18" tft displays (£7 or $11 each! ) and need to obtain/make cheap 24V 2.5A power supplies for the working ones. I think they'll end up costing more than the displays.... Mark

Maybe the secretary of IEC SC3C should make his dictats easily findable and easily readable on search engines or he'll just get ignored... I haven't even come across an electronics book that actually tells you what that symbol really means. M.K.

Thanks to you and all others for their replies. Mark

I read in sci.electronics.design that snipped-for-privacy@digiverse.net wrote (in ) about 'Quick power supply question', on Tue, 11 Jan 2005:

See my previous post in this thread regarding IEC SC3C that deals with these symbols. Go to

Search for '3C' where it says 'TC/SC dashboard' in the right-hand column, and then click 'General Information' on the resulting page. You will find the contact details of the Secretary, Professor Ikeda, there. Tell him what you want, preferably with a simple proposal.

Maybe something like (ASCII art; use Courier font): __R__ -----

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that snipped-for-privacy@digiverse.net wrote (in ) about 'Quick power supply question', on Tue, 11 Jan 2005:

He did at one time; he set up a free database on his university computer, but the IEC found that it was affecting sales of IEC 60417 so it had to be discontinued.

Publishing such a book would raise serious copyright issues, of course, if it were comprehensive, but I suspect IEC would allow a modest selection to be published without an exorbitant license fee. You can get PD 6578:1995 from British Standards, but it's costly and if you want it, be quick, because it's proposed for withdrawal. It has the advantage that the symbols are not superimposed on a grid.

--
Regards, John Woodgate, OOO - Own Opinions Only. 
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

Here's a 24V/6.5A switching supply for $34.75:

-- "To deny our impulses... foolish; to revel in them, chaos." MCJ 200308