DMX Adapters; Another 5 pin to 3 pin DMX question

The output of your board should hit the opto-splitter first. That way, any electrical malfunction will take out one of the outputs on the opto-splitter as compared to taking out the board! It can be located in the booth or at the stage, but it should be the first thing in the chain. From there on out it is standard "star" topography. Each output can chain up to 32 fixtures or dimmers. In most cases, it is better to use each output to handle a "zone" of lights. That way, if there is a problem, you can narrow it down to the zone that is misbehaving.

3 to 5 and 5 to three adapters can be used anywhere you want. Just don't mix the type of cable you are using! (Use only DMX data rated cable, not mic cords.)
 
Exactly as JD says, go to an opto-splitter. The key thing of an opto-splitter is not only does it split the signal into various outputs, but they are all optically-isolated, that is to say they are not directly electrically connected. If something happens like 120v applied to a pin of the dmx in one of the lights, it will limit the damage to only that part of the chain from the splitter. It is protection!
Also as JD said, never put more than 32 devices on a single DMX output. you can start to see some ugly things start to happen. You also don't want miles and miles of cable on a single output.

In my opinion (yes I know not everyone wants to buy one) EVERY lighting setup should have an opto-splitter, why not?

Splitters come in all different sizes and such, and made by different people. Their quality does vary a little. Price does too.

A pretty typical sort of setup:

Board (Console) -> opto-splitter (in)
opto-splitter -> Dimmer1 -> dimmer 2 -> dimmer 3 -> etc -> terminator
opto-splitter -> moving lights -> terminator
opto-splitter -> accessory power supplies (PSUs for scrollers, I-Cues, etc) -> terminator
opto-splitter -> LED fixtures
opto-splitter -> more LED fixtures.

You get the idea.
Use 3-pin to 5-pin and 5-pin to 3-pin adapters anywhere you want, as JD said make sure you use the same type of cable (all DMX cable not mic cable). Going from one cable type to another also causes problems.
 
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A few questions:
Any hints for us on what the box in the booth is? Is it just a patch panel, or actual equipment? If it's an inline opto, you could replace it with an opto/iso that has a few more outputs.
On your drawing, the four lights labeled "Stage Lights" all get three-pin cable too. I assume that it's power rather than DMX, but just wanted to verify.

How close to the stage is the room with the dimmers? You could get signal to the stage devices from the pass-through on the dimmers. It might be easier than a home run back to the board.

Depending on placement of the FOH mover, you could run to it, then back to the box in the booth. It's hard to tell you which path to take without seeing the space.
Yes ok.
The dimmer pack shown on the picture. It says it is a Betapack 2 made by Zero 88, same as the lighting board. I'm not sure what the actual name for it is, but you have the stage light number above and you plug them in accordingly, to give power and to patch them.

Yes the stage lights are big metal 3 pin power cables which plug into plugs at the ceiling and run to this cupboard, which supplies them with power.

Yes, with regarding to hooking up all the dmx lights I have done that already. From the moving one, I have trailed a DMX cable to the ones backstage, and yes the backstage lights are close to the cupboard, but would it work if I simply plugged it in and addressed them?

Thanks
 
The output of your board should hit the opto-splitter first. That way, any electrical malfunction will take out one of the outputs on the opto-splitter as compared to taking out the board! It can be located in the booth or at the stage, but it should be the first thing in the chain. From there on out it is standard "star" topography. Each output can chain up to 32 fixtures or dimmers. In most cases, it is better to use each output to handle a "zone" of lights. That way, if there is a problem, you can narrow it down to the zone that is misbehaving.

3 to 5 and 5 to three adapters can be used anywhere you want. Just don't mix the type of cable you are using! (Use only DMX data rated cable, not mic cords.)
As I do not have many dmx lights, only 3, could I just use a dmx splitter cable instead of an opto splitter. This means one side would be for the stage lighting, not dmx and one would be for the dmx lights.
 
As I do not have many dmx lights, only 3, could I just use a dmx splitter cable instead of an opto splitter. This means one side would be for the stage lighting, not dmx and one would be for the dmx lights.
The simple answer is no. You cannot passively split a DMX signal. What happens is you end up with data reflections down the different legs of the split that will garble the data.
 

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