I'm sorry but I have to agree with Derek here. It is utterly irrelevant that the cannons were
fed off a
dimmer. Now while we may not have concocted the idea of half these things back in 1990 when the original
DMX standard was written, they were most definitely around when DMX512A was written a year or two ago. And it's a technical reason...
The
DMX protocol is based around RS485, a common serial
protocol used rather frequently in industrial control
etc. But it's just a hardware
protocol, it says nothing about data. The
DMX standard when originally developed was there to control lights on dimmers. nothing more. So as a data
protocol it does what it was mean to, but it does not have any inbuilt error checking. So if the data gets garbled along the way, the dimmers will just take it as is, it might be missing a couple of channels out of the middle say. Your dimmers go funny for a frame or two, no real potential for harm. Even these days, you get some wigglies wiggling when they shouldn't, not going to end the show. BUT, if you have a
cannon on the end of it, or a
kabuki drop, or
pyro, or any of the other no nos, then if that controller gets muddled data, you can have the thing go off, without someone having done the kosher thing and visually confirmed all is
clear. You can attempt all you like to convince me otherwise, but a
cannon misfired has the potential to cause serious injury. Say someone was sitting on it at the time...
At any rate, you had your
dimmer set as on off? Well unless you can hear a
relay clicking over, it's not really on off, the
solenoid is getting dirty
power and in good time will
express it's dislike of it...
Sorry, you hit the nerve, I, Derek and a collection of others on here just don't take
safety lightly, it's too much of a risk, especially given that we have an audience of primarily high school students who might be inspired to do something without having the skills or thinking to make sure that it will, in all aspects, be safe. So while we get up on our soap boxes and lecture, we do have everyone's best interests at heart when we do...