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bklynsoulja

under-powered cable question

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hello, i currently have those cheap premade bnc cables that like 24 gauge(guessing) from ebay 60ft. Powers a cheap camera no problem but now i want to install a IR camera. I tested it with 2amp power supply and at night it gets video loss which i know is under powered from the wire. than i put a 3.5 amp power supply and it works. Is that safe? Also is it safe if i cut part of that cheap cable(where i can get access to it coming out of the wall because the rest was installed when house was renovated) and solder and shrink a cat6 wire to it? 1 pair for video and the 3 other pair for power? so a cable that starts with 24 gauge wire than half way down becoming 20 gauge wire from the 3 pairs of cat6? would that help or is that a hazard?

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Use the older power caable to pull the new CAT5 (or Cat6 as you prefer) one through, When doing this with my installas I do the following;

For the

first four cameras I use the Orange pair for Video

for the second four cameras I use the Green Pair for Video

for the third four cameras I use the Blue pair for video

and the fourth four cameras I use the brown pair for the video.

If there are any more cameras I start with a new CAT5 with a different Jacket colour.

 

I always use the white striped conductor as the positive for Video and Power.

 

Now take the remaining pairs and separate out into white stripe and solids

twisting all the white striped together, and all the solid colours together tightly.

The white striped bundle carries the +ve and the solid colour bundle carries the earth

 

I personally use crimped on ferrules onto the video pair and the power bundles

0.25mm for the video pair, and 0.75mm - 1.00 for the power bundles.

 

Do the above at each end terminate the video pair with balun.

 

NB: CAT 6 is hard to work with (Cat5 is more forgiving) and is for a reason unknown to me as yet,

is more susceptible to breakage during handling. There is little or no advantage in terms of transmitting

power over the conductors and voltage drop between the two is minimal.

 

 

241573_1.1241573_2.1

241573_3.1241573_4.1241573_5.1

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If you suffer from lower voltage i.e. voltage drop over a long run of cable, then sometimes you need to start with either a higher voltage and a good power rating. This is easier said than done as we cannot always find a reliable economic small variable power supply, so there are other practical solutions.

 

Typically we do this;

Start with 24Volt AC and use a drop transformer of the correct rating i.e. 12vDC with a suitable current rating at the camera end.

Then you will have a solid 12V supply at the point of delivery.

Alternatively, use 24V AV cameras since AC volts suffer far less from voltage drop than DC power.

 

241575_1.jpg

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thanks but is it ok to use like let say 25 ft of the cheap premade bnc cable and cut it and splice it with a cat6 cable (1 pair for video, 3 for power) ? would that be dangerous to have two different guage wire spliced together? right now i can leave it alone and use a 3.5 amp power supply which will work, but i feel like cutting whatever i can get access to that coming out of the wall and splice it with cat 6.

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thanks but is it ok to use like let say 25 ft of the cheap premade bnc cable and cut it and splice it with a cat6 cable (1 pair for video, 3 for power) ? would that be dangerous to have two different guage wire spliced together? right now i can leave it alone and use a 3.5 amp power supply which will work, but i feel like cutting whatever i can get access to that coming out of the wall and splice it with cat 6.

 

Your picture is likely to be unuseable. You have a fairly severe impedance mismatch (the cheapo coax supposidly 75^ & the cat 5/6 at 100^ ) If you can get it to work ok with the existing cable then do so OR as Numbnuts has said , pull in a new cable (best option)

 

@ NUMBNUTS - good post on those voltage converters, I'll have th check em out. Any further info?. I've been making my own but they look obviuosly "homemade" & are about 3 times the size of the ones you've shown.

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thanks but is it ok to use like let say 25 ft of the cheap premade bnc cable and cut it and splice it with a cat6 cable (1 pair for video, 3 for power) ? would that be dangerous to have two different guage wire spliced together? right now i can leave it alone and use a 3.5 amp power supply which will work, but i feel like cutting whatever i can get access to that coming out of the wall and splice it with cat 6.

 

Your picture is likely to be unuseable. You have a fairly severe impedance mismatch (the cheapo coax supposidly 75^ & the cat 5/6 at 100^ ) If you can get it to work ok with the existing cable then do so OR as Numbnuts has said , pull in a new cable (best option)

 

@ NUMBNUTS - good post on those voltage converters, I'll have th check em out. Any further info?. I've been making my own but they look obviuosly "homemade" & are about 3 times the size of the ones you've shown.

 

thanks imma try, cant pull a new cable as the old stapled in and would just rip it and than i would have no wire

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If the cable you wish to remove is the DVR end, then you would need to put a balun either end of the patched line, one where it enters the DVR and one where it connects to your original cable, but I have to say that you would probably be better off leaving it alone.

In other words, things will probably get worse not better.

 

For what it's worth, my opinion is this,

either replace the entire cable (which you've said is not viable)

or leave it alone.

Anyone agree or have a better suggestion?

remember not everyone has the same level of skill

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If the cable you wish to remove is the DVR end, then you would need to put a balun either end of the patched line, one where it enters the DVR and one where it connects to your original cable, but I have to say that you would probably be better off leaving it alone.

In other words, things will probably get worse not better.

 

For what it's worth, my opinion is this,

either replace the entire cable (which you've said is not viable)

or leave it alone.

Anyone agree or have a better suggestion?

remember not everyone has the same level of skill

 

your probably right, i am just going to leave it alone and use a 3.5 amp power supply to power up the camera since anything less than that wont work due to the cable being cheap.

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inmho youd be better to pull a new cablein and not try using old cable thats not fit for purpose surely you can go thru the loft or lift a couple floorboards to get a new cable where it needs to go.

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