Using cat5 cable for power

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indudio

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Hi,

I am currently looking for ways to make some wiring harnesses for my controllers (ray wu 27 channel). After looking at the 8+ core wires available and there prices, I would like too know if I could use cat 5 cable for this, connecting to D sub connectors either end.

As cat 5 is 8 core, I would be looking to run 6 (-) and 2 (+) meaning there would be 1 common positive for each 3 channels.

This is to run at 30v for big w strings. Most of the channels the total current will less then 100mA, and from my understanding this is ok as each wire in the able can have upto max of 1Amp.

So will this work?

As cat 5 cable is a lot cheaper then other multi core cable.
 

AAH

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Big W strings are likely to be about 6W so at 30V they're only pulling 200mA which is no biggy for cat 5 cable. Try to ensure you are using stranded rather than solid cat 5 cable as it's a lot less likely to break.
 

jeffl

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I have some of the same questions. I'd like to use it to power some dumb RGB nodes. I use it to power some MR16's now and it works great for that.
 

fasteddy

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One thing to be very cautious about with using CAT5 cable for power is not to use solid core. The reason being that CAT5 solid core is designed for permanant installations, so if you use solid core for temporary installations like in your display you then run the risk of a core breaking in the cable and then this can start to overload the other cores that are sharing that current. In a bad enough situation you can overload the cable and cause melt down. So even though CAT5 solid core is very cheap its not the best thing to use for running power in temporary situations.

300 metres of 4 core 14/020 alarm cable delivered is under $100 so thats not a bad price at all

300 metres of 6 core 14/020 alarm cable is not much more

Solid core CAT5 may not give you any issues at first but by the 3rd year you may start getting issues as the cable gets used and the chances of cores breaking increases. So trying to save $40 to $50 now on cheap CAT5 may cost you a lot more in the future. Just something to be aware of
 

AAH

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If you can source it for a reasonable price then cat 6 is better than cat 5 as it is 22 AWG compared to 24 AWG. This is 0.644mm compared to 0.511mm for those that live in the modern world.
 

Binkles

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I hadn't thought of that.. I was thinking of using cat5 for everything.

Will rethink that.
 

David_AVD

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CAT5 can work fine for what you intend. Yes, the solid core type will break after it's been flexed a lot so stranded would be better if you're still keen.
 

fasteddy

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The issue with stranded CAT5 and CAT6 is the cost, so this is why i find the security/alarm cable to be the best value choice.
 

fasteddy

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2012 saw me update all my network cabling as i originally used solid core, but after a few failures in 2011 i decided to use all stranded CAT6 for 2012.
 

fasteddy

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David_AVD said:
Some people buy a $80 305m (1000') box of CAT5 for DMX and Ethernet though and end up with a lot left over. ;)

I find its actually cheaper to buy pre made CAT5 and 6 stranded network cables from EBay instead of spending the effort making them up and using solid core to save a couple of dollars. Some things i find are not worth the effort or risk.
 
I

indudio

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I am actually making these for permanent installation. Our new house starts getting built next week. In the front yard I will be running 90mm drainage PVC throughout the front yard underground to breakout points. This will connect directly into the garage where all controllers will be housed. Longest cable run will 20m.

I Will have heads and tails for this, so I can place caps over the PVC pipe and leave multicores in there.

I was looking at the security core wire, but I would need 6 lengths each of the 6 core to make 1 multicore for the ray wu board. Seeing as I am most likely to have around 15 of these controllers this year, that would be minimum of 1000 meters. As opposed to only needing about about 800 meters or so of the other cable.

However, I do want to set this up right - would solid core installed permantly be ok? Or should I go just go with the security cable ?
 

fasteddy

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indudio said:
I am actually making these for permanent installation. Our new house starts getting built next week. In the front yard I will be running 90mm drainage PVC throughout the front yard underground to breakout points. This will connect directly into the garage where all controllers will be housed. Longest cable run will 20m.

I Will have heads and tails for this, so I can place caps over the PVC pipe and leave multicores in there.

I was looking at the security core wire, but I would need 6 lengths each of the 6 core to make 1 multicore for the ray wu board. Seeing as I am most likely to have around 15 of these controllers this year, that would be minimum of 1000 meters. As opposed to only needing about about 800 meters or so of the other cable.

However, I do want to set this up right - would solid core installed permantly be ok? Or should I go just go with the security cable ?
This is where pixels become far better to use because you dramatically reduce your cabling needs and cost in cabling.
But solid core for a permanent installtion that you are planning is very acceptable to use because it wont be moved, disturbed, stepped on or kinked in your situation. Just be aware that you should only use 1 amp per core with CAT5 and you will have to take into account the common return current with any RGB lights which will carry 3 x the current than the output so you will have to double or triple the common return up depending on the load you plan on having with that output. The other thing you must take into account is voltage drop, so if you are planning on having long runs from the house to the lights then you will need to double up cores to reduce voltage drop. Using LEDs that are controlled from a DC board use a current limiting resistor and are voltage dependant, so the more voltage drop you get the less intensity you will get from your LEDs

But if your planning on RGB i definetly wouldnt be taking the path you are because it can cost just as much as if using pixels and then daisy chaning data from one element to the other using a ECG-P2. You could then run out a heap of thicker guage 2 core cables for power injection, and because pixels use constant current for control then the lights are less effected by voltage drop and you would have to see a voltage drop of 3 volts or more before the lights are effected. Just an alternative that you may have not considered.

Finally what voltages and lights are you planning on using as this will play a big part of your design and if the CAT5 will be acceptable to use or not.
 
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indudio

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Thanks eddy.

This is just for the big w strings I have. Most of them are only in lengths of 100 or less, but are for my mega tree, mini trees, leaping arches etc. They will be running 30v, but most of them will be less then 100mA per channel.

I intend on using dumb rgb to outline the house and roof, but will be using the 4 core security wire I have for these.

I totally agree with you on pixels and the plan is to transfer to these starting in 2014. For this year though, as budget is limited and the fact I have about 30,000 LEDs in string lights already, I unfortunately have to go down this track. But I am putting the infrastructure in during the house build so it will be easy to update later.
 
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