how to split data (and power?) to RGB arches

kane

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Oh and one more thing - I always put an inline fuse between the power supply and any cable that I run out to the display. This is designed to cover any shorts that could then overload the cable and cause nasty surprises.. Others don't bother, so again it's up to personal preference, but I've had at least 5 fuses blow due to wiring issues, and much easier to replace an inline fuse than dealing with fuses inside boxes (or worse still, fried controllers!)
 

bernard

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Kane said:
I always put an inline fuse between the power supply and any cable that I run out to the display. This is designed to cover any shorts that could then overload the cable and cause nasty surprises..
interesting. How do you size the fuse? lower rating than the power supply one so it blows first?

Kane said:
If you've got plenty of 3-core connectors, you could simply use those (just use the two wires), it's personal preference, and many people do that - I just prefer to be able to distinguish them.
I saw in another threat someone using SPT1 cable for power supply for the exact same reason (distinguish)... why not!
 

kane

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Generally the size of the fuse should be at around the maximum rating for the cable. So that if there is a wiring issue, the fuse blows.. So a 10A cable, stick a 10A fuse in.

If your power supply has a fuse, then that's probably on the 240v side of things (the input), rather than the output.
 

fasteddy

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Kane said:
If you've got plenty of 3-core connectors, you could simply use those (just use the two wires), it's personal preference, and many people do that - I just prefer to be able to distinguish them.
I find if you have 3 core cable or a spare core and your using for power injection then its best to connect the 3rd/spare core to the +V, the reason for this is that you effectively reduce 1/2 of the return power path resistance by 1/2 so you effectively reduce voltage drop.
Just make sure you dont connect the +V or ground to your data pin on your plug
 

David_AVD

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If I were using 3 core cable for DC, I'd double up the -ve wire, not the +ve wire. The reason is that you're better off reducing the drop in the -ve wire as that is what the pixel data (or clock if present) signals are referenced to. This will give you a better noise margin for those signals.
 

fasteddy

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David_AVD said:
If I were using 3 core cable for DC, I'd double up the -ve wire, not the +ve wire. The reason is that you're better off reducing the drop in the -ve wire as that is what the pixel data (or clock if present) signals are referenced to. This will give you a better noise margin for those signals.
Makes more sense as you still have the exact same power adavantage regardless if you connect the +V or ground, but as you explained this will give a bit more resistance to noise if connecting the ground to the 3rd core
 

bernard

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So I finally got my 2811 strings from Ray. Very odd though as I got 2 strings of 40. On one end of the strings, I have a red/green/black wire and on the other end I have a red/green/black + another black and red! should not be a big deal as the 2 reds are connected together to the same terminal in the RGB and same thing for the black. I guess I can simply cut off the extra 2 wires, right?

Before I connect anything, how do I know which wire is the data, ground and +5V? I can't make up what is written inside the RGB even with a magnifier (too hazy). If I wire it wrong, I assume it will damage the string.

Thanks for any suggestion you may have
 

bernard

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The red is on one end it looks like that there might be a + sign above it. The green is in the middle and the black on the other end.
 

AAH

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The 2 extra wires will be for power injection of 5V at the end of the string. Seeing as how it is red and black that are power it's a pretty safe bet that the green wire is your data. There might be an arrow to indicate data direction on the pixel or there might be a tiny DI and DO indicating data in and data out.
 

Charl Marais

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Agree with the post above. I asked for power injection points from Ray on my last order and was told that it is now generally included on strings as many people were asking for it.

The extra two black and red lines are thus for power injection at the end of the string.
 

bernard

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That is awesome, both the design and your responses! I was concerned the additional wires was a sign of poor manufacturing but feel better about the all thing now.
I have 3 strings, 2 of 40 pixels each that have 5 wires and 1 of 20 pixels but this one does not have the extra wires for power injection. I now wish it had those extra wires built in.
Thanks again for your help!
 

bernard

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Any reason why I could not use regular lamp cord (SPT2) for the 5V power injections?
 
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