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#23446 - 03/19/03 03:10 AM Switch noise w/Flourescent
minangelo Offline
Junior Member

Registered: 01/29/03
Posts: 9
Loc: Ogunquit, Maine
I have a customer who asked me to check switches that made an arcing sound when she turned them on. When I got there I got there I noticed that she had flourescent bulbs instead of the incadencent that these switches operated. I told her that the flouresent bulbs had a starter on them and recommeded we test the switch with regular bulbs. The sound went away. I do not think she needs to worry about the sound. It only makes the sound when you operate the switch slowly as she does. Any one have any thoughts!


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#23447 - 03/19/03 03:38 AM Re: Switch noise w/Flourescent
sparky Offline

Registered: 10/18/00
Posts: 5545
are we saying the starter draw was the cause of a switch arc here?

#23448 - 03/19/03 07:40 PM Re: Switch noise w/Flourescent
frenchelectrican Offline


Registered: 02/06/03
Posts: 938
Loc: Wi/ Paris France { France for ...
there is the other way the reason to hear the noise is the snap switch or have loose connection somewhere if that switch is old snap type it can crakle some if new one then have momtery surge run thru the switch and most morden switch are fast and quiet

merci marc
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

#23449 - 03/20/03 10:33 PM Re: Switch noise w/Flourescent
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
Its not actually the starter that causes this switching arc, it's the ballast, the coil of wire that limits the current to the tube(s).
When a magnetic field is de-energised, the back EMF, causes a surge across the switch contacts.
What I would recommend you do is upgrade the switch to a higher current rating, what ampacity is in there at the moment?.
Let's face it, these days if you're not young, you're old - Red Green grin


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