Control/Dimming DMX beginner

[btlauer]

Hello,
I am pretty new to anything DMX and recently I undertook a little project in our theater spaces to add some new DMX control points.
Our building has two spaces, each with their own Lighting boards but with shared dimmers. We are able to switch control via a handy little toggle switch. I'm not sure what the wire runs look like yet.
My question has to do with adding new input points backstage so that we can hook up a small lighting board (or whatever) backstage for class projects and whatnot. I'm wondering what I might need to accomplish this. Will I need an optical splitter and just switch out boards when the occasion calls? Or am I way offline and all I need is to hi-jack into the middle of the run and put in a couple jacks backstage.
Thanks.
Ben

 

[SteveB]

I believe the ETC standard (as example) is to allow one middle DMX input point in a DMX line, thus you can have a booth location with a console OR, having un-plugged the booth console, then add a console to the intermediate input, but not 2 consoles inputting at the same time.

Option 2 is separate home-runs of DMX to a merge unit, which then outputs to the dimmers, which allows both consoles at the same time, in a highest-takes-precedance scenario. At that point you need to remember to be sending zero values on the booth console in order for the added console to have control. DMX merge units run $1200 or so ?., maybe cheaper if used - which is an idea as there's really no moving parts on one of these.

Steve B.

 

[gafftaper]

It depends on your dimmer rack for starters. My rack has a DMX A and DMX B in. If you had a setup like that then it's just a run to the rack. On the other hand you might need some sort of Merge unit. I would take a look at the dimmer rack specs... or post the rack make and model here and someone can help figure it out for you. Also take a look at Doug Fleenor's website. He makes all the parts you will need. Have you considered wireless DMX? It might not cost much more and would be a lot easier. Looks like a Doug Fleenor wireless solution is about $1700 vs $1300 for a merger. You could also use the wireless to put out DMX to some exotic locations in your theater making it a lot more useful. Looks like W-DMX has some cheaper wireless prices... I don't know much about the various wireless DMX products... thats the topic of another thread.

 

[TimMiller]

When i had to setup a dimmer rack to share two spaces i used dmx line A for one space and B for another. Then it was set to merge based on HTP (highest takes presidence) and then set one console to run off of channels 1-24, then patched the other to run off of 25-48. If you have a rack with more than one DMX input you could probably do this, if not then you will have to get a dmx merger. The reason it costs so much, is that it takes the signals from both consoles, combines them, reclocks and then resends the signal as one output. Now elation has come out with this toy that will fix your problem DM-2512R - Elation Professional
i bet what they did is install a two pole switch that switches the data +, and - wires to the dimmer rack. You can splice into the data line in the theater and add another input port. If you go past two total ports you may start to run into data problems.

 

[SteveB]

Now elation has come out with this toy that will fix your problem DM-2512R - Elation Professional.

Nice unit, until I got to the section where it indicates 3 Pin XLR.

Idiots, and yes I know that's probably the connector all over their fixtures. They're still idiots.

Steve B.

 

[SHARYNF]

One approach is to have a panel in the new location that does hi jack into the middle of the run BUT have the run from the console go to a jack, the have another jack from the dimmers, this way you can have a short jumper cable to connect the cable and bypass the "insertion" point. Merging equipment is pretty expensive, a and b input on the dimmer is a possibility, but the jack panel is an easy solution Just make sure that you have the jumper cable in place when you want to run the other controller location.

You MIGHT be able to put a switch instead get a multi pole switch with one connection path going to the usual controller position and the other to the jack, personally I would rather use the jumper cable

Sharyn

 

[lieperjp]

Well, I don't know how "recommended" this is, but just this winter we took an Elation DMX splitter with two inputs (a 3-pin and a 5-pin) and used both. We have our Smartfade (or mobile board in the center of the auditorium) hooked up to the 3-pin using a converter and our main board (a Leviton Innovator in the booth) hooked up to the 5-pin. It works as long as one and only one board is on, with two boards on the system freezes.

 

[Anonymous067]

It works as long as one and only one board is on, with two boards on the system freezes.

At least your system only freezes when its a human error. Ours just randomly freezes. Sorry to hijack. Proceed.