From: Rob Peacock
Subject: Re: Computer Controlled Pyrotechnic Firing Panel
References: <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com>
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Date: Wed, 18 Sep 2002 00:33:22 GMT
NNTP-Posting-Date: Tue, 17 Sep 2002 17:33:22 PDT
Organization: EarthLink Inc. -- http://www.EarthLink.net
Andy, I thought you had all of this under control when we talked about
it. If you didn't feel comfortable with some of the details, why
didn't you ask?
You would be surprised what is used for shooting commercial shows. Be
aware that this equipment is not required to undergo UL testing
certification, or anyone else's certification, for that matter. Many
of the very best systems, that are considered the diamonds in the
industry wouldn't pass most of the tests required for any UL
certification, nor should it be required to.If there was any
definition of digital, it would definately apply to firing systems.
It's either off or pushing 1A - 5A through each ematch, with the
exception of a continuity test of 10mA - 15mA.
One of the companies I have shot for uses a modified nail board and it
works great. The biggest problem is the connections on the slats
spinning and breaking the wire on the inside.
As Mike and Andy have already mentioned, once the pyro is onsite, the
shooting location gets locked down to anyone except the AHJ and the
crew. Once the pyro is being loaded/wired, the chances of an outsider
getting inside the perimeter is slip as the crew is on the lookput all
Also, most firing panels tend to be 100-200 feet from the mortars.
There isn't a mile of cable out there (well, maybe in scab wire but
that's a different story). There have been issues with lightning but
there are also certain procedures that are *generally* followed. For
the most part, the only thing that happens is that the cables are
disconnected from the slats/rails. This reduces the antenna effect.
Some systems are designed to shunt the matches but of the several
hundred pyros I know, very few do it, and only under certain
As far as the regulations that were mentioned, you are probably
referring to NFPA 1123, 1124, and 1126. If you read those very
carefully that they give very few specifics and a lot of generalities.
*Most* states follow the NFPA guidelines although there are a few
states, like California, that go off the deep end and regulate the
hell out of it, like everything else.
Mike was right when he said that there isn't usually an issue with
setups due to the firing systems. If they work the first time, they
will typically work for many years before a failure. The only failures
I have heard of consisted of:
1) A homebuilt system used in a commercial venue that the operator
applied power when one of the pyros was still placing product.
Normally, this wouldn't have been a problem although it isn't
generally acceptable. There was a solder bridge on one of the PCB's
and it caused one of the airbursts to fire (out of 35 already
2) There was a miswire in a commercial system that circumvented the
current limiting resistor in the continuity circuit and caused the
entire show to go at once. "Thanks for coming out folks, hope you
enjoyed the show, please come back next year."
3) A commercial software revision/version incompatibility caused a
choreographed show to go in the wrong order, and was stopped before
the whole show went. Show was a fiasco to begin with but was
There are times when fireworks should be considered explosives but
there are also times when you don't need to be anal about something
because it doesn't matter - *sometimes* it *is* rocket science.
On Wed, 04 Sep 2002 22:35:29 GMT, jimf@DELETEME.pobox.com (Jim (from
>There will certainly be, at least, a common law duty of care and I'm
>sure using a system designed by someone with very little knowledge
>of how to design it would breach that. I doubt an insurance company
>would like it either.