Cable Length 12V

[studiouk 0]

Hi,

 

We install cctv systems using CAT5e (Full Copper) and we use the standard power and video baluns.

 

We use 1 cable per camera. Blue and Blue White for the Video and the rest for the power.

 

We normally use a 12V 6A for up to 4 cameras.

 

We always install infrared dome cameras

 

We never have an issues with power on run up to over over 150m.

 

We want to try using less cables. So we want to use 1 cat5e cable for two cameras. Use 1 pair for video and 1 pair for power. This leaves us with two pairs for another camera.

 

This has worked fine but can any tell me:

 

"what the maximum cable length can be" using 12V only using on 1 pair of wires instead of the 3 pair of wires

 

Thanks

 

Phil

[Securame 0]

That will depend on the material of the UTP cable; the width of the cable; the quality of the power supply; the AMP requirements of the camera you are installing; etc...

 

So, to answer the question, you have to try it. With the cable you are using on your installs, with the power supply you are using, the cameras you are using, and so on.

[the toss 0]

It truely amazes me that " we install cctv systems" but we don't have a working knowledge of ohms law.

[Billy_ICU 0]

The problem is "voltage drop". That can be determined with a voltage drop calculator for DC (Direct Current).

 

Input [to calculator] DC voltage, size of wire in gauge, length of wire, metal wire made of (copper/aluminum), and the amperage load at the end of the wire run - in this case mA.

 

To find a voltage drop calculator, search google.com for the following words...

 

voltage drop calculator DC

 

Tools to help with this are an amp meter to measure amperage draw and a multimeter to measure voltage. Manufacturers are not very good at telling you the technical specifications of things these days. You are lucky to find the model number of the cameras included in the package (let alone amperage draw day/night)!