From: John Woodgate
Newsgroups: sci.electronics.design
Subject: Re: TRIAC "wears out" on dimmer circuit
Date: Mon, 11 Nov 2002 21:29:25 +0000
Organization: JMWA Electronics Consultancy
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Reply-To: John Woodgate
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I read in sci.electronics.design that David Lesher
wrote (in ) about 'TRIAC "wears out" on
dimmer circuit', on Mon, 11 Nov 2002:
>John Woodgate writes:
>
>>>>The inductors in European dimmers have MANY more turns, on much larger
>>>>cores.
>>>Is that because our cycles are slower than the US breed
>
>>No, it's a much larger difference than could be accounted for by the
>>difference between 50 Hz and 60 Hz. In fact, the supply frequency is
>>irrelevant. I don't know why the US dimmers can use what must be quite a
>>low inductance, only a few microhenrys if they have 6 to 10 turns.
>
>Is the inductor bigger to help meet the EU's RFI regs vs the US's
>likely far more tolerant ones...?
>
Possibly, but the higher supply voltage and lower current might actually
cause the required inductance to be larger anyway.
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
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