Just checked my connections all on

 

Just checked my connections all on

Meaning all 9 LEDs?
What does the meter read?

 

Ok to recap
R 0.33a
G 0.19a
B 0.04a
Think I broke that second board getting good at this

 

Try this:
Connect R and B to negative but connect the G to +12V, read meter.

 

G 0.78a

 

Good, that's what I was expecting.
Apparently the RGB lines need to be connected to +12V and not left floating.
Try again with the Blue

 

B 0.79

 

B 0.79

And again with the Red.

 

0.33a

 

All on 1.82a

 

0.33a

Fantastic!
We're done.
I'll calculate the resistor values needed later

 

Awesome thanks, im off to bed knackered cheers again

 

Good, that's what I was expecting.
Apparently the RGB lines need to be connected to +12V and not left floating.

As I suggested in post #12.

 

You did, but I had no idea what that meant, I appreciate all the help thanks everyone. sghioto has the patience of a saint.

 

You did, but I had no idea what that meant, I appreciate all the help thanks everyone. sghioto has the patience of a saint.

All right, give me one more chance then.

Here is what I think.

1. The fixture requires the +12V and ground from the power supply always.

2. The DMX controller outputs 0V when the LED should be on, and floating when the LED should be off.

3. The fixture expects 12V on R G or B to turn the LED on and 0V to turn them off.

4. For some unknown reason, the R input seems to act like it is at 12V when it is not connected, and the G and B inputs do not.

5. An inverter, like the one you tried, will reverse the logic of the signals, making the DMX signals compatible with the fixture signals, and will provide the correct 12V and 0V signals for on and off.

6. The DMX controller must have pullups on the R G and B outputs to provide correct logic levels as inputs to the inverter.

7. The pullups suggested in 6 were the only thing missing in the setup with the inverter, and it would have worked correctly had they been installed.

8. And finally, and very important, the GND of all power supplies must be connected together. It is unclear to me whether this is the case for all the things you tried.

I do not believe any modification of the fixture modules was ever required. I just think that we never got all of the required elements correct in any trial.

 

I do not believe any modification of the fixture modules was ever required. I just think that we never got all of the required elements correct in any trial.

I would agree.
Anyhow the resistor values needed are:
RED LEDs = 15 ohm, 5 watt
Green LEDs = 4.7 ohm, 5 watt
Blue LEDs = 3.9 ohm, 5 watt
Available at Amazon: Resistors

 

Suggest unsoldering pin2 of the DD311 chips and bend the pin up out of the way.
One end of the resistor if space is available will solder to the this spot and a wire soldered to the other end going to the DMX.

 

Ok thanks everyone for the input (pun intended) will order the resistors and get back to in a few days. I really appreciate all your help and can only apologise for my lack of understanding and thank you for explaining it in ABC terms for me, you are all a credit to electronics and I promise this will be my first and last attempt at anything like this again.

 

Just to check all other wiring remains as is untouched is that correct? just the correct resistor added to the R G B circuit on pin 2 of mosfet?

 

Just to check all other wiring remains as is untouched is that correct? just the correct resistor added to the R G B circuit on pin 2 of mosfet?

Won't need those RGB wires connected where they are currently.
I suppose the wires could be used to solder to the resistors
The Negative wire will not be used can can be removed making a 4 pin connection to the DMX, 12V R G B