Was CAT5 a mistake?

[cctv_down_under 0]

My installer has run cat5 for a site I am doing with 50 odd cameras, some of the runs are over 150 meters and I suppose this is why he did it (wish I knew I would have just used the XF camera), he is using a passive balun at the camera end and a rack munted recieving station (also passive) that recieves 4 x cat 5 and converts to coax, I am concerned with running 24V AC on such small wires and within the same sheath, can there be some issues with this becasue some of the cameras will draw at least 500ma?

[Doug 0]

At 500ft you will probably need an active balun at the head end.

 

The voltage drop at 500ft drawing 500ma on 24awg even if you double up for power will be severe. http://www.altronix.com/app_notes/calc.php

 

I haven't seen any interference issues running AC or DC in the same UTP cable

 

Doug

 

My installer has run cat5 for a site I am doing with 50 odd cameras, some of the runs are over 150 meters and I suppose this is why he did it (wish I knew I would have just used the XF camera), he is using a passive balun at the camera end and a rack munted recieving station (also passive) that recieves 4 x cat 5 and converts to coax, I am concerned with running 24V AC on such small wires and within the same sheath, can there be some issues with this becasue some of the cameras will draw at least 500ma?

[phred 0]

My installer has run cat5 for a site I am doing with 50 odd cameras, some of the runs are over 150 meters and I suppose this is why he did it (wish I knew I would have just used the XF camera), he is using a passive balun at the camera end and a rack munted recieving station (also passive) that recieves 4 x cat 5 and converts to coax, I am concerned with running 24V AC on such small wires and within the same sheath, can there be some issues with this becasue some of the cameras will draw at least 500ma?

 

 

On 24 volt power - Voltage drop on the longest run is way too high.

One answer would be using higher voltage and drop down transformers

 

Double the voltage - would allow half the current and half the voltage drop and you are almost there.

[cctv_down_under 0]

how much voltage drop will I get on cat5 using 24vac at 120 meters

[phred 0]

how much voltage drop will I get on cat5 using 24vac at 120 meters

 

depends on current draw

 

for .5 amps through a 24awg conductor, voltage drop would be around 10volts

 

at half the current the voltage drop is halved, but you would then only get half the power.

 

I think you may need to go to 60 volts then use a step down transformer.

[gthms 0]

You should not have any interference with the video signal on that (or greater) distances. Just make sure the CAT5 is unshielded.

 

If 1 CAT5 to each camera you can double up on the pairs for power with 1 pair for video.

 

Also there are 16 channel passive receivers out there (rack mounted) if you wanted to save some space in the cabinet

[cachecreekcctv 0]

Small wire guages were just not meant to move current through, only signals. Like trying to use a Serial cable for power. Amperage, whether AC or DC, depending on the current "draw", needs larger wire sizes to prevent overheating the wires' insulation. Some cameras , though, only pull 3 to 4 watts, so that is very minimal. "Ampacity" of wire is always to be taken serious. 24AWG wire is just so small, I would have a hard time trying to draw any sort of current through it, especially on a long run.

[phred 0]

Possible solution.

 

Assuming 1 cat5 for each camera.

 

Use one pair for signal and three pairs for power. Voltage drop should be only 2 volts with 600ma current – some cameras will tolerate this drop.

[cctv_down_under 0]

Looks like it will be ok, the Bosch cams operate at 12vac to 28Vac so should be ok, I will definately use two wires for power and double up the guage - so long as the installer did not go for several cams in one cat5.

[rory 0]

Just dont try to power anything like an EX82 with Cat5, even if it is trippled up .. at least not with 12VDC - been there done that.