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How to prevent a triac from causing Incandescents lights to flicker

How to prevent a triac from causing Incandescents lights to flicker

How to prevent a triac from causing Incandescents lights to flicker

(OP)
I currently have a 100 ohm and .1uF across the MT1 and MT2 terminals of the triac and currently have a flickering occurring. When I am connected to building power =no problem. WHen I am connected up to a generator that's when i get the problem. DO I know have sufficient snubber across the triac?

RE: How to prevent a triac from causing Incandescents lights to flicker

I presume you mean flickering when the triac is OFF?

You may not need any snubber depending on what your load is.

More info..

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: How to prevent a triac from causing Incandescents lights to flicker

If the problem just happens with the generator, that is where I would look for the problem.  A capacitor line to neutral before the dimmer would probably help more.  The generator doesn't have a low enough source impedance and one dimmer is triggering another.  I have seen this with other phase triggered devices and have solved it with RC on the input.  I used two .47uf 22 ohm snubbers in parallel on each device.

RE: How to prevent a triac from causing Incandescents lights to flicker

Following Opera's suggestion; do compute the powers the snubber components will see..

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: How to prevent a triac from causing Incandescents lights to flicker

(OP)
HI All
I am using a zero cross detector chip placed at the front of my ac input connection, to detect AC voltage zero cross for phase control. I would think the RC snubber on  the front end would delay the zero cross detection for every 1/2 cycle??
Maybe I could place a snubber circuit at the mains distribution (input) that feeds 3 light dimmer circuits?

RE: How to prevent a triac from causing Incandescents lights to flicker

Cap won't do anything like that. It might get rid of a few false zero crossings.  Just how big is this generator?

RE: How to prevent a triac from causing Incandescents lights to flicker

How stable is the generator frequency?
 

----------------------------------
  Sometimes I only open my mouth to swap feet...

RE: How to prevent a triac from causing Incandescents lights to flicker

Is this a power factor issue?

RE: How to prevent a triac from causing Incandescents lights to flicker

The triac is used as dimmer -- i.e. with phase shift
whics depends on frequency.

Fuse:
You nee, I'm afraid, a more complicated scheme -- so back
to the drawing broad.

Why don't you tell us what you are trying to do ?


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