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Topic Title: Measured loop via dimmer switch
Topic Summary: Odd reading ?
Created On: 25 April 2014 06:11 AM
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 25 April 2014 06:11 AM
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SherlockOhms

Posts: 320
Joined: 05 April 2011

Chaps,

I feel I should know this but, I don't. Feel free to chastise as appropriate.

Installed several lighting circuits all fed via a 4gang dimmer plate.

R1r2 checks out fine but when taking a live loop reading I'm getting >200 ohms on one Cct.
I stripped and checked everything and eventually traced it to what would appear to be a faulty dimmer. When I swap the Cct to another module all is good.

Is this simply a dodgy dimmer?

Many thanks.
S.
 25 April 2014 06:20 AM
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Thripster

Posts: 639
Joined: 22 August 2006

Think I would bypass dimmer switch(s) whilst testing.

Regards
 25 April 2014 06:28 AM
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aligarjon

Posts: 2811
Joined: 09 September 2005

i have never been able to test through a dimmer. i always bypass them now.

Gary

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Specialised Subject. The Bleedin Obvious. John Cleese
 25 April 2014 06:45 AM
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GeoffBlackwell

Posts: 3505
Joined: 18 January 2003

Is this simply a dodgy dimmer?


No but it might be after being subjected to the test .

Regards

Geoff Blackwell
 25 April 2014 10:03 PM
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sdjl

Posts: 17
Joined: 21 July 2010

http://www.theiet.org/forums/f...id=205&threadid=19250

"It would be wrong to consider a dimmer as resistance, its a phase cutting switch, letting current through on only part of the cycle, this does reduce the RMS current that can be drawn, but you'll not be able to get any sensible reading as the instrument is most likely not designed for bastardised waveforms!"
 27 April 2014 07:06 PM
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davebarman

Posts: 285
Joined: 27 February 2006

Whoops.

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Never knock on Death's door. Ring the doorbell and run like hell, he hates that!
 27 April 2014 08:41 PM
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mantutu

Posts: 42
Joined: 16 June 2013

I actually joined this forum because I thought it was full of engineers doing what I do. I am so disappointed but never the less entertained.
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