Max distance with 12 Volt

[gar32 0]

Hi all,

 

Most of the installs I have done have been resedential or shops and didnt require a long cable run.

 

My problem is now I have a warehouse install job and the distance is over 100Metres to some cameras.

Will a 12 Volt camera struggle at this distance?

Should I go for a 220 Volt (mains camera)?

 

Thanks

[gfdcxgfd 0]

I would like to know this as well. The most distance I am going in no more than 250 feet.

 

Will a 12 volt system suffice or should I go with a 24 volt system?

[gar32 0]

Isn't there a formulae to calculate this?

[rory 0]

Some links regarding this:

http://www.cctvforum.com/viewtopic.php?t=9945&postdays=0&postorder=asc&start=15

http://home.hiwaay.net/~rgs/awgcalculator.html

http://www.video-insight.com/Support/Tools/Wire-Length-Calculator.aspx

[gar32 0]

Great thanks!!

[VST_Man 1]

The bigger issue here is amps and how many you need at the end of the wire. Depending on the device rated amps usage, you may have the 12VDC but not enough amps. How will you know? Use the large guage of wire when going long distances.

 

ie: I have a PTZ at the end of a 200ft CAT5 wire. I had to instert 15VDC and double up on wires to carry the needed amps & volts. I used an adjustable PS and adjusted to 12vdc with it powered on. BUT, I've ran 300ft. 12vdc to a bullet camera that drew only 350mA and got away with it.

 

Long distance solution; use AC where applicapable.

[percy 0]

We just finished installing nine cameras in a strip mall. We used RG59, with 18 gauge wire and 12V power supply box. All our camera runs were over 400' with one run being 700' and we had no problem using 12VDC voltage on any of the cameras.

 

But to be on the safe side I had cameras the would take both 12VDC or 24VAC and a dual voltage power distribution box.

[Javik 0]

Regarding the use of mains / line power, there is a limit to the maximum voltage that can be run without being in conduit in a commercial building. The cutoff is somewhere around 90 volts (I don't have an NFPA rulebook), and if you go above that you are going to have to use conduit.

 

This is why you don't see cameras with power requirements going beyond 50 volts or so. By staying at a relatively low voltage, your installation is exempt from the conduit requirements and you can build it cheaply.

 

 

If you must use line power for a distant camera, it would make much more sense and be far less expensive to just run the conduit from the nearest breaker panel, install a 1-camera power supply right next to the camera, and run only the video/data signal lines back to your central cable plant.