Advice on sending power over 900 feet [24ACV + cat5]

[Xive 0]

Hello everyone

 

Currently I'm installing a CCTV System for a residential zone. The system consists of 14 cameras which have a range from 50-900 feet. What I've decided so far is to use cat5 with baluns, all powered by a 24ACV Altronix multi camera power supply.

 

However before commiting to a specific cable and setup I'm very concerned with the distance of 900 feet. Can someone please tell me about the possible problems I can face? Or better yet if they can recommend the right way of sending power and receiving video from a camera 900 feet away.

 

I've searched the forums and I have not been able to find a straight answer to this type of issue.

 

Thank you very much for your time.

[Soundy 1]

Should be easy to find info - it's covered regularly, and there are a lot of wire calculators linked to from here.

 

According to this one, and assuming a 500mA draw over three pairs: http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=84.22&voltage=24&phase=ac&noofconductor=3&distance=900&distanceunit=feet&amperes=.5&x=34&y=18

...you'll see a 7.7V drop, for 16.3V at the camera.

 

Depending on the camera, this may not be an issue (many dual-voltage cameras will work with anything from 10-30V, AC or DC). Obviously the drop is greater if you only use two wires, or if the camera draws more current (built-in IR, for example).

[Xive 0]

Thank you very much for your question. I'll look into the calculators. The power supply I have in mind is able to switch between 24VAC and 28VAC.

[hardwired 0]

If you are using Altronix supplies (good choice, BTW), the models that offer 28 volt outputs can help you overcome the voltage drop of long wire runs.

 

900 feet is about at the point where you may want to consider using baluns with an amplified receiver.