DMX Shortcut?

[HOYS]

For my school, I am thinking of using a DMX controlled light from the catwalks. The board for lights is in the back of the auditorium. To run a DMX cable it would be about...300 some feet without being noticeable. Is there any way to patch it through the dimmer racks or something? :huh: Don't get mad at me or anything, I have NO experience with DMX things at all.

 

Thanks!

[Nick S]

Simply put - no, you won't be able to plug it through the dimmers...sorry! There are ways around it (such as doing it wirelessly), but if it's just one run I can't see the point (and you probably don't have the budget). Normally it's fairly easy to conceal a cable, if you run it along bars, corners, etc.

 

If you were interested, Avolites do make a box that lets you send up to four DMX universes down a mains cable, using the ethernet over mains technology. But again, I can't see the point for just one cable!

[GridGirl]

Are your dimmers closer to the DMX light than your lighting desk? If so, you can run the DMX out of the dimmers rather than out of the desk - your dimmer packs will have a "DMX out" or "DMX thru" plug on them. Might save you a lengthy cable run....

[HOYS]

Are your dimmers closer to the DMX light than your lighting desk? If so, you can run the DMX out of the dimmers rather than out of the desk - your dimmer packs will have a "DMX out" or "DMX thru" plug on them. Might save you a lengthy cable run....

 

Yeah, our dimmer racks would be about 75 feet away and upstairs with the catwalks where the board is 300 feet away.

[Andrew C]

Two options:-

 

1) Take a cable from the DMX OUT or THROUGH on the dimmers to the light

2) Buy or hire an isolating splitter and split the signal at some point before the dimmers.

 

Advantages and disadvantages in both schemes.

[ampcats]

How are your racks connected to the board? - if it is DMX - as I assume, then you can plug your intelligent fixture into the DMX loop through on the last dimmer rack - (or DeMUX if you still use analog dimmers)

making sure that you terminate the DMX at the last fixture, and turn off / remove the termination at the last rack.

 

If you are not sure if you are using DMX / AMX / analog / D54 / other... then tell us what board, racks and 'other boxes' that have to be turned on for the lights to work that you are using, and we can work it out for you...

[HOYS]

Our school uses a Strand 520i board and the Strand CD80 Dimmer racks.

 

The board is connected to the racks with a DMX cable. The thing that I dont get about our school is how it was wired. In the booth there is a port for the DMX to board but there are other ports too which I have no clue what they are used for. We have 3 places were these plugs are, stage left, center of the audience (for dress rehersals but we never use it because its a pain to move the board) and obviously one in the booth.

[woody74]

...but there are other ports too which I have no clue what they are used for. We have 3 places were these plugs are, stage left, center of the audience (for dress rehersals but we never use it because its a pain to move the board) and obviously one in the booth.

 

Is it possible that the other ports in the booth are pass-thru ports to the ones in the house, or possible DMX distribution in the catwalks?

[pritch]

In the booth there is a port for the DMX to board but there are other ports too which I have no clue what they are used for. We have 3 places were these plugs are, stage left, center of the audience (for dress rehersals but we never use it because its a pain to move the board) and obviously one in the booth.

 

What sort of points are these? Male? Female? XLR? Three pin? Five pin?

[HOYS]

I havent seen them for a bit because our last production wrapped up about a week ago. I'm guessing (from memory)

 

There is a green three pin female socket I belive and another 3 pin male connector of some sort. I'm not the best at these things so it could be XLR or DMX, I'm not sure.

[ampcats]

if it was part of a professional install, the school would have records of it (if only on the succesful quote / invoice) - which would tell you what these sockets were for and where they lead to...

 

are you sure it is not a socket for a riggers remote?

 

without knowing what these sockets are, daisy chaining out of the CD80's is your easiest option.

[pritch]

There is a green three pin female socket I belive and another 3 pin male connector of some sort. I'm not the best at these things so it could be XLR or DMX, I'm not sure.

 

If it's 3 pin, then is shouldn't be DMX. Chances are it's some sort of audio thing. Maybe a pair of sockets for plugging cans in or something.

 

Technically speaking, only 5 pin XLR should get used for DMX, although 3 pin is used on lower end kit.

[paulears]

As I see it, you have a decent desk and dimmers in a huge theatre - a cable run from back of auditorium to the stage area that is 300 feet long is pretty massive for a school. If your building is this big then surely there is a proper infracstructure for the cabling?

 

One of the other posters asked about how the wiring to the dimmers was done. At some point, the daisy chain to the dimmers will stop - probably internally. Not normally a problem to take this unused output and drive your new DMX line from there - distance a lot less. You could use the other tie-lines if they are wired with decent cable (or at least try) even if they are wired with 3 pins, not 5 pins - IF they terminate somewhere useful on stage.

 

Your profile doesn't say where you are, which is a shame, or we could help more.

[HOYS]

I'm from the US.

 

We have a large capacity theatre (787 seats!) but it wasnt well planned on the lights side of things. The main Dimmer racks are on the catwalks, where the dimmers for the house lights are outside of the theatre, up stairs, and in a boiler room.