Mighty Scan Help

[brozeph20]

I was setting up our theatre's mighy scans this past week and I encountered a problem. When I plugged the DMX cord into the fixtures, all of them turned on immediately and rebooted. The kept on rebooting until I uplugged them or disconnected the DMX cord.
We have a second dimmer rack for a newly added system of lights. This is controlled through DMX port 2 on orur ETC 72-144 light board. This cord runs upstairs. We then ran another cord from the output on this dimmer rack back down to the booth to plug into our house light wall panel (our panel splits the signal into a few different outputs at other parts of the theatre). I then ran the cord from our house light panel backstage onto the electric and into the fixtures.
Before we started, all of the lights were controlled together on the same DMX dimmer(s) out of our DMX port 1 on the board (we changed it to DMX port 2 so it wouldn't interfere with the existing lights - controlled through DMX port 1 - and that they could all be controlled using the same cord - just daisy chained from fixture to fixture). By using this set up, all of the lights worked - now we just want to control them all seperately.
Any help would be appreciated greatly - thanks.

[lieperjp]

Was the DMX Line terminated?

[brozeph20]

No, we didn't teminate it at the last fixture - we never have and it has always worked.

[julzzw]

Originally Posted by brozeph20

No, we didn't teminate it at the last fixture - we never have and it has always worked.

It is probably a good idea to though, now that you have more nodes on your DMX. As DMX systems get more complex, you have more chance of signals being bounced back through the line.

[len]

It sounds like one of 2 issues:

Termination, as has already been discussed, or

The fixtures are receiving a reset command somehow. It could be coming from the desk, so try re-booting, and/or clearing out the library. I don't know that desk well enough to say much more about it.

[brozeph20]

would just the end plug to an XLR cord work as a terminator - the system worked a couple of years ago without a terminator (or they used this - I can't contact the people who set it up before). Is there any other problem that it could be?

[Pip]

Originally Posted by brozeph20

would just the end plug to an XLR cord work as a terminator - the system worked a couple of years ago without a terminator (or they used this - I can't contact the people who set it up before). Is there any other problem that it could be?

Nah, it has to electrically terminate the flow of signal through the cable, to the tune of 120Ohms of resistance. Here's a great article on DMX termination:

DMX Terminators

And here is a nice DIY article:

DIY DMX Terminators

[brozeph20]

I know that this is late but...

Originally Posted by len

The fixtures are receiving a reset command somehow. It could be coming from the desk, so try re-booting, and/or clearing out the library. I don't know that desk well enough to say much more about it.

When you say library, what do you mean? Is it the fixture library because nothing is in it?