How to add floods to setup running DMX2-24

SimoG

SimoG

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May 8, 2023
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Location
Cleveland, Brisbane
Evening All!

Last year you were an amazing help with my setup issues, and hope you can help with my current challenge.

Last year I ran a DMX2-24 with a FPP on Beagle Board to bring my Bunnings fairy lights into sync (Thanks to @AAH and @David_AVD for their amazing support). This year I have purchased a second DMX2-24 and Power Supply to add some additional lights.

I want to add some flood lights into the display, to light up a printed fabric hanging on the Garage Door. I am looking at a few options for adding the flood and want a fairly cost effective solution. I am currently looking at:
  • Use a resistor/Diode to drop the voltage from the DMX2-24 to run 2 x Kings (12/24V -14W ) flood light.
    • Full bogan option, but trying to use what I already have
  • Buy a 12V pixel flood (and the required hardware)
  • Run fairy lights around the edge of garage door.
  • Run a 240V Flood which isn't synced with display - Simple timer to control.
    • Is there a way to easily include the 240V this with the display?
Fairy lights will be the cheapest, however pixel flood would be the best option. I think I could drop the voltage of the DMX2-24 for a automotive (24V) flood light, and get the best of both worlds

I am keen to get advice on this. I'm torn as setting up some pixel lights/models is likely the next step, but I'm trying to push that out to be a future Simon problem(Xmas 2025).

Thanks in advance!

Cheers
Simon
 
Just go full bogan and just send it. I expect that your lights are likely 31V and as such that's the power supply/ies that you have on hand. A 24V vehicle with motor running is likely to be around 28.8V. The 28.8V is probably close enough to 31V that there's no issue. It's entirely possible that you could connect a 24V 14W flood directly to the DMX2-24 and it will work. The output driver chips used have a 2A current limit built into them so you will be well below that level.
 
That is amazing! Easier that I thought. I will wire them up and check the throw, however I expect I will likely keep it well below the full output.

Should I place a diode on the circuit? or just make sure I don't use the the other channel?

Simon
 
You'd get 16 bit dimming because of the polarity changes, which is what would be needed for full brightness.
Otherwise, a diode or only using a single channel would limit you to 50% duty cycle
 
Thanks @Skymaster, I don't think the reduced duty cycle will be an issue. The Diode (and resistor) was what I did to include a 3.XV circuit last year, assumed I Would need it for this setup as well

I want to run 2 floods due the angles, and due that that, I am confident I only need a relatively small % of the output.

Which leads onto the next questions. Can I connect to negative of both floods to a common channel on the DMX2-24? while it wouldn't make difference with 2 floods, it I run a third, it would allow me to include an extra run, if a common neg / ground is used for the floods.
 
Skymaster said:
You'd get 16 bit dimming because of the polarity changes, which is what would be needed for full brightness.
Otherwise, a diode or only using a single channel would limit you to 50% duty cycle
Click to expand...
Nope.
The dimming is entirely 8 bit. The led flood will only conduct in 1 direction. The alternating polarity will reduce the potential brightness to half what it could be at a fixed 31V. Depending on any smarts inside the flood it may current limit things and there would be no brightness change between about 23V and 31V. IF there is no or limited smarts in the flood then running at 31V at 50% duty cycle could actually be comparable in brightness to running at 28V at 100% duty cycle due to the non linear relationship between voltage and current with leds.

The use of a diode shouldn't really be needed. Just connect directly across outputs 1 and 2 and the next flood would go across 2 and 1 (ie the polarities are swapped). Using a diode may be problematic unless it's a "fast" diode. The switching/dimming frequency of the dmx2-24 is fairly fast and a common garden variety 1n4004 or similar are quite slow.
 
Full sent it :) and no luck. I get light output, but very dull.

Tested with the Test Harness in xlights. Changing the highlight intensity in the test options from low to high, and besides some faint flashes no change to the output. The flashes appeared to be similar to the PWM strobing effect I get on some torches.

I did wire up the red wire from the lights into port 24, and the black to 23. I assumed (and initially tested) on port 24 in xlights, however it would only light up with port 23 was active.

I realise this is completely unsupported use of both products, however if anyone has any insights into what is going on / how to get it working it would be awesome! What would cause a light bar to go to such low output? protection circuit?

Cheers
Simon
1725176622174.png
 
The strobing and low brightness is likely due to whatever smarts are inside the flood. Adding a diode in series may provide better results. Having the voltage reversing could potentially be problematic for the electronics and the recovery time from the reversed voltage may cause an issue. I've never tried it but it is quite possible that connecting between the incoming V- and an output may work and get rid of the need for a diode in series.
 
As always. Thanks for your help Alan.

I didn’t quite follow the comment incoming V- and an output. I assume V- is the black wire off the LED light. What is the output in this scenario?

Either way I may grab a diode to see how it improves the scenario. It is a fun concept and keen to get this working without buying more hardware.

Cheers
Simon
 
The black wire of the led light to the incoming "black" wire from the power supply. The output is pretty much exactly the same as if a diode is put in series. IF there was no smarts inside the flood then you could this method for any led.
 
Tested again and no cigar. I tried a few different tests, including Black --> 0V, Red --> 0V. And in both scenarios I was getting no output on the light bar (compared to the low output in other tests)

I re wired it to 2 (numbered) terminals, and still seeing the low output. (I don't think I have blown the light).

I then added a string of working fairy lights in parallel on the circuit to make sure the ports were working.
When first channel was output (Light bar Red cable) - Fairy Lights On, Light bar off
When Second channel on, (Light Bar Black Cable) - Fairy Lights OFF, Low output on Light Bar.

Unless there is a sudden idea on what could be going on, I am tempted to put this down to a fun experiment, but an unsuccessful one. However I still want my flood lights for the display :)

Any guidance on how best to add in some floods? For general info, this is what we are wanting to light up

1725272252535.png
 
Leave it to me for a bit. I suspect the issue is because the floods are a 12-24 universal style and there's electronics in it to do some dimming to emulate the voltage.
 
Those floods dont look suited to the DMX24, the look more suited to the dmx36mk2 or the new switch from baldrick
the dmx24 is for polarity swapping for 2 wire fairy lights
the light you have would be 12-14V direct voltage - being a kings vehicle spot light
 
Juddge said:
Those floods dont look suited to the DMX24, the look more suited to the dmx36mk2 or the new switch from baldrick
the dmx24 is for polarity swapping for 2 wire fairy lights
the light you have would be 12-14V direct voltage - being a kings vehicle spot light
Click to expand...
Hence the cunning plan I have in mind :D
 
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