Projector on Dimmer Board

In school for the musical, we will need to hang a projector from the stage rigging. The projector is controlled via cat5, which is being run back to the control booth. My plans on power, however is to set channel 12 to 100%, and plug it in (with a resistive load). Will this damage the projector? All of the receptacles are controlled via. a 144-channel dimmer pack.

 

Dimmer packs have to be specially designed and manufactured to cope with inductive loads. I would suggest making a call to the manufacturer to verify what your trying to do. Having an inductive load coupled with the resistive load may not solve the problem.

 

Does the dimmer board have a patch panel in back where you could disconnect stage circuit 12 from dimmer 12 and connect the circuit to an ordinary receptacle (may need to make a 2 or 3 round pin stage lighting receptacle to 15 or 20 amp 120 volt plug)? Then you could plug in the projector up in the rigging and it would work correctly and safely.

 

Don't plug the projector into any dimmable circuit. If you have 144 dimmable channels then you aren't going to have a patch bay. You'll need to run AC to that projector from a standard receptacle.

 

Every dimmer circuit (which happens to be almost every receptacle on the stage) runs back to a large dimming console, similar to what's pictured. Each group of four pulls out, and the back comes off the dimmer. I can probably un-wire the one channel and wire it to a non-dimmed breaker. (regular QO style) which the board has about 20-30 spaces for.




That is my plan B. Wouldn't that violate code though ty-rapping orange extension cord through the auditorium?

 

Wow. An oldie but a goldie. I haven't seen or worked on one of those since the one i started on when I was the age you are now. A real blast from the past. Enjoy.

You don't have any direct-wired receptacles in the wings?

 

Temporary wiring..............................

 

Because you can control the projector via Cat5 you shouldn't need to switch the source power at all. It's also never a good idea to power it down during a show. Instead, switch whatever video source you're using to a "superblack" screen (RGB values of 0,0,0) until you need it.

 

They're all wired to the dimmer board, even the floor receptacles.


We aren't planning on switching power, we're planing on tapping power.

 

Pulled the board open today. Wired channel 12 to a regular breaker, so it is always on. I'll post pictures when I'm home later tonight. I'll be hanging the projector tomorrow after school.

 

You solved it, but is there no regular panelboard there?

Oops, nevermind. But why not just go from that breaker to the projector?

 

That dimmer panel feeds all of the 120V circuits on the stage side of the auditorium. There is an electrical room nearby which houses I think 4 or 5 panels and the transformer which feeds the dimmer board. Why they didn't add any non-dimmed receptacles is beyond me.


Front of dimmer.


Back of dimmer with cover removed. Notice the large copper busses.


Rear of dimmers.


Breaker which controls aisle lights and nightlight receptacle. I used this breaker to run channel 12.

 

I was going to say, the newer dimmer packs can be set to switch at either 0% or 100% (I forget what the feature is called, it's been a while), but that one is definitely old enough to not have that feature.

The last time I used a projector in a theater, we set up a blackout screen in front of the projector. Most projectors still produce light even with a fully black screen. So we added a black painted cardboard square about 12" square that could be raised and lowered in front of the projector lens a few inches in front to completely back it out.

Sounds like a fun project!

 

Got the projector hung today, as well as 150' or cat5 and VGA cable. All is working great! For giggles I even added a green S14 bulb up there. Only downside is having to take the sizzor lift back in there to take everything down

Thanks for stopping me from possibly frying the projector.

 

Awesome job

I'm noticing missing dimmer packs. Are they starting to fail ?
You're actually pretty lucky to have that many dimmable channels at your disposal. Most schools don't come anywhere near close to that.