Rgbwa dmx decoder

  • I’m making my own rgbwa controllers. I bought some cheap halogen work lights and took all the guts out to use as my fixture. I need a very small dmx decoder for the 5 channels so that each fixture can be daisy chained by dmx. However i have not been able to find any small 5 channel dmx decoders, only 3 channel ones. So could I use two mini 3 channel dmx decoders instead?

  • JPK

    Approved the thread.
  • Hi!


    Yes, certainly you can use two of the 3 channel decoders. Just leave the "channel 6" without connection and give the next controller the startadress #6.

    The only thing you have to consider: the specifics of DMX says, that without a repeater you only can attach 32 devices. In reality this depends on your outputinterface and your cables. Using two 3 channel decoders instead of one 5 channel allows you to use only 16 of your rgbwa-devices before you need an active repeater (or splitter).

    If available, you could also use e.g. 10 channel controllers and leave 5 of them without connection. All of those mixes are not relevant for the function of DMX itself.


    Hoc

    Mein Equipment:
    1x Hirn | 2x Augen (leicht defekt) |2x Ohren | 1x Mund |32x Zahn (zum Teil V1.5) | 1x Handundfuß-Interface

    *SCNR*

  • Thank you. I had another question that I was wondering if anyone would be able to ask. I plan on using two of these in each fixture. https://www.mossled.com/produc…cw?variant=15745552252987

    They’re 3 watt rgbwa modules. But do you think two 3 watt modules is bright enough to be seen?

  • Hi,

    for which kind of application do you want to use your fixtures? 3 watt LED modules can be seen, but they are not very bright. Usually, LED fixtures contain at least 4 to 7 LEDs of that kind (or with much more power) to produce a certain ammount of light output. But on the other side maybe the brightness is enough for your kind of application. Therefor just tell us, what you plan to do with those fixtures.

    regards

    JP

  • Hi,

    for which kind of application do you want to use your fixtures? 3 watt LED modules can be seen, but they are not very bright. Usually, LED fixtures contain at least 4 to 7 LEDs of that kind (or with much more power) to produce a certain ammount of light output. But on the other side maybe the brightness is enough for your kind of application. Therefor just tell us, what you plan to do with those fixtures.

    regards

    JP

    I need these fixtures to act as accent lights. They need to be bright enough to light up a person or prop from a couple feet away. I could try to use 3 modules in each fixture instead, which would be around 9 watts. Or even a foot each of this https://www.environmentallight…t.html#tab-specifications

    to tape around the aluminum reflector

  • Hmmm, as mentioned in the specs of those 3W LED modules, they have a beam angle of 120°. This and with the fact that they have only 3 watts would lead to a very low amount of light and I would say, that this is not enough in bright areas. But maybe, you can buy just two or three of them to build up a prototype. Them you can see, if they are bright enough.


    P.S.: I would not use LED stripes because their beam angle is usually even higher.

  • Hmmm, as mentioned in the specs of those 3W LED modules, they have a beam angle of 120°. This and with the fact that they have only 3 watts would lead to a very low amount of light and I would say, that this is not enough in bright areas. But maybe, you can buy just two or three of them to build up a prototype. Them you can see, if they are bright enough.


    P.S.: I would not use LED stripes because their beam angle is usually even higher.

    I could try to put some 30 degree lens on the individual leds? Do you have any better recommendations on what to use as the light source for the fixtures?

  • I have a counter question. What is the reason you want to build that kind of spot's yourself? Is it "just 4 fun" because I imagine that when you sum the costs of all the pieces together you can also purchase off the shelf LED Floorspots.

    I am asking because if I am looking ahead, planting all of these LED Modules in the housing and taking care of the thermal management will be a challenge. Unless this project has also a DIY component included I doubt that this makes sence.


    I am just asking to get a better understanding of where this all should lead to.


    Answering your question, normally LEDs don't have a reflector in the shape of the work Lights, the lens shape is cone shaped and you have multiple of these. I think your best try is putting 3 of these inside the housing with a 30-60 degree Lens and not use the original reflector. Nevertheless 9 Watts is still not very bright. Also the 3 Watts is per Module, which means the individual color is less. You only have 3 Watts if you run these modules on "Full On" mixing RGB and Whites.


    To give a comparison, the "small" Eurolite PS-4 HCL Spots I am using (https://www.thomann.de/de/eurolite_led_ps_4_hcl_spot.htm) have 4x12W which means, each LED Module has 2W per Color in total 8W per color. As mentioned I consider these spots small so you can use them in groups or for small areas if it is not to bright. I would not go for less wattage if you really want to use them as light source.


    Regards,


    Arne