Well are we talking about a
dimmer module like one from a sensor rack, or are we talking about what I refer to as a
dimmer pack or like a set of 4-12
dimmer circuts all enclosed
in one box that is
fed from one
power input?
In the case of a
dimmer pack, I don't think you are having any problems or electrical phonomena. The dimmers that I have at school run on two legs of
power a.k.a. 240v and we use regular 120v fixtures and in my years at the
theatre, we have never had a
fixture explode. To explain this, when
power enters the
dimmer it is usually split in half so that one
leg feeds half the channels, and another
leg feeds the other half of the channels. In my case one
leg feeds 3 channels at 2.4 Kw each thus requiring 60 amps, then the other
leg feeds another 3 channels requiring an additional 60 amps. This doesn't however mean that I need a 120 amp
breaker, I just need a 60 amp 240v
breaker because that delivers 60 amps per
leg. If you don't believe me, follow the "signal" path. Look at a schematic for a
dimmer on how to connect the
power cable and you will see that there are two separate legs that feed the 2 halfs of the
dimmer each running at 120v each.
What I am curious about is how many channels this
dimmer is considering that it only runs on 20 Amps. If I ran the numbers correctly, you would only have 2 channels at 2.4Kw being
fed by 240v.
If I am wrong about you using only a
dimmer module, then certainly listen to what the people who posted above me have to say because it sounds like in the case of a
dimmer module that you would have something seriously wrong.
Once again I claim no amazing knowledge of electricity or lighting, my primary job is as a sound tech as my signature says. I just study electricity because it seems to be becomming common that everybody expects the sound personel to deal with
power and know how to
wire things correctly. Plus its always good to be well rounded when you work in the
theatre industry, or any industry for that matter.