Control/Dimming - Multi-port DMX switching unit

[wah0808]

First let me say that I did do a search and didn't find anything that really resembled what I trying to do... or at lease what I searched on didn't lead me to anything that sounded too similar.

That being said... Every two years I'm TD of an a community Ice Show. The lighting grid is permanently wired with 12 circuits, I have another 3 on the back wall and 3 colour 'bang boards' (ice level marker lights) giving me a total of 18 circuits. Currently these are controlled via two banks of relays connected to a switch box in the booth.

Since introducing moving head lights a few years ago I now have two control units. One is my laptop via a usb to DMX interface and one is the antiquated control board (mentioned above) build before I was born...

I'm looking to purchase (or plans to build) an 18 channel DMX controlled switch to replace the current board allowing me to control the existing relays. Everything I've found that is commercially available is a low voltage to high voltage relay (or dimmer), or is just a single switch; that would be rather expensive to replace 18 switches. Also seeing as this is a community skating club (and the show is every other year) I'm trying to do this on a reasonable budget.

I have the relays I just want to replace the switches...

Any ideas?

Thanks...

[NickJones]

So you are looking to DMX control them to control on your computer? This will cost you a few hunderd dollars and take a while. But can be cool if you can do it. If that is what you want to do, I'll give you a write up.
Nick

[wah0808]

That is exactally what I want to do... Basically I have two goals, 1) replace the board of 18 switches, 2) control the moving head lights and relay switched circuits with one board (in this case my laptop, unless I grab a small board off ebay...)

thanks,

Alan...

[epimetheus]

What's the coil voltage on the relays? If it's 48V DC or lower you could use one of these. I found these a few months ago and ordered one for some LED projects. I drive it with my laptop and BlueLite X1 Mini.

If the coil voltage is AC, check this out.

[wah0808]

Originally Posted by epimetheus

What's the coil voltage on the relays? If it's 48V DC or lower you could use one of these. I found these a few months ago and ordered one for some LED projects. I drive it with my laptop and BlueLite X1 Mini.

If the coil voltage is AC, check this out.

Interesting, I have to double check... but as far as I know one bank is 12V and the other bank is 24V ... So the first board may be the answer...

Thanks!

Alan...

[wah0808]

After another look at the circuit board I'm not sure that solution would work either. The voltage is already provided in my case... I'm just trying to control the closing of the circuit (ie. just replacing the switch) If I were to use that board I would have to drive another relay to act as the switch... not a huge issue I guess, but it seems like it's over complicating things...

Please stop me if I'm missing something here. I may have to go back to the drawing board and try to trace exactly what I have. The setup at the arena is over 30 years old so there is no paperwork.

I don't want to have to replace the relays and I'm certainly not looking at replacing the control cable (as it runs to the other end of the Arena).

The idea is remove a switch and replace it with a DMX controlled switch * 18 ...

The more I think of it the more the first solution with separate relays looks like the only answer.

Alan...

[Footer]

Whats the load on each of the relays? You might want to look into getting some shoebox dimmers, might be a cheaper solution.

[Dover]

Three of these DeMux units from MA Lighting would do what you want. The relay based version comes in a case or as a pc board that you would need to mount them in a case. I would recommend that you go with the pc board units and mount all 3 in the same case. It would make the whole system more reliable to have the connections in a case.

[wah0808]

Originally Posted by Dover

Three of these DeMux units from MA Lighting would do what you want. The relay based version comes in a case or as a pc board that you would need to mount them in a case. I would recommend that you go with the pc board units and mount all 3 in the same case. It would make the whole system more reliable to have the connections in a case.

That looks like it would do the job... Only question is how would one daisy-chain 3 together?

Thanks.

BTW...

Here is an image of the switch board I'm trying to replace...



Alan...

[epimetheus]

That MA Demux unit is the same type of board as the Blue Point one I linked. If the relay coil voltage is DC you can use the first board I linked without any additional relays. The positive voltage from the system would connect to the LED+ input and the positive side of the relay coils would get commoned together and connected to system positive. The negative side of the relay coils would connect to the LED1 thru LED18 headers. The LED- terminal would then get connected to system negative.

Whether you can use the 32 channel board I linked is really dependent on what the coil voltage is, AC or DC.