Powering Cameras Over Cat 6 Cable

[larrymilla 0]

Hi,

 

I'm on an installation of an NVR system. I'm thinking of using 2 pairs for video and the other 2 pairs for Power by allotting each pair to both live and neutral respectively. I plan to use the 'power pair' as an extension of the 12v/5v DC adapters for the cameras.

 

The shortest of my camera is about 20 meter long.

 

Do you think I'm on the right path?

 

Please I need your advice!

 

Thanks....

[Soundy 1]

If you're using an NVR, I assume that means network cameras... meaning Power-over-Ethernet is the preferred way to go. Pick up a small PoE-capable switch, plug your cameras in, and you're good to go!

[larrymilla 0]

Thanks soundy,

 

My problem is laying my hands on a PoE switch as it's not readily around. I live in Nigeria and I'll definately need to place an order for it, which might cost me additional 2 weeks or thereabout to wait, which my client does not want to hear, but instead I'm thinking of using 4 of the 8 pieces of Cat 6 cables, pairing them in 2s to power the cameras while having their camera 12v adapter plugged to the power source.

 

Will it ever work that way? or can anyone here advice me better?

[RDeSmet 0]

As long as you are not using Gigabit ethernet, which most IP cameras do not do, you are only using 2 pair for network connectivity, so that leaves 2 spare pairs in the cable. Most network cables are wired in the T568B standard. Which means that the orange and green pair are being used for your network connectivity, you could pull out the blue and brown pair on each end of the cable and use that for your power.

[Soundy 1]

RDeSmet is correct - 568A or B both use only the green and orange pairs for data for 10/100Mbit, so the other two pairs can be used for power - it's cheesy and ghetto-fab, but it should work. 12VDC should be fine over two pairs for only 20M.

 

(The difference between A and B, BTW, is in the orientation of the two pairs - 568A puts green on pair 1 and orange on pair 2; 568B reverses those... a cable with A on one end and B on the other is effectively a crossover cable.)

[Sawbones 0]

Ghetto-fabulous is still fabulous!

[larrymilla 0]

Thanks guys, I'm going to commence the installation tomorrow. I so much appreciate your inputs.

 

Then, I've got another question, among the cameras I'm using for this installation, I've some of the cameras using 5v DC and most of them are using the regular 12v DC adapter.

Now I'm thinking of centralizing the power distribution by using the regular PC power pack for the power supply, how do you see this?

 

Also, I'm concerned about the Amperage. The 5v adapter requires 2.5A while the 12v needs 2A, will the Amperage from the regular power supply be good enough to power the cams?

 

Thanks for ur usual aids.

[Soundy 1]

I doubt the power supply "requires" that amperage - power supplies are typically rated by how much they can *supply*. Devices that run off them are rated for how much they require. Cameras are typically well under 1A, sometimes as low as 200mA. As long as the sum the current requirements of all devices doesn't exceed that of the power supply they're attached to, you should be fine.

 

I WOULD be concerned about the potential voltage drop of 5VDC over Cat6 cable, although it shouldn't be an issue if the runs aren't over 20m. What IP cameras are you using that require only a 5VDC supply, though?

 

The question about using a PC power supply for running cameras has been covered here many times - it's generally agree that you can do it, but it's not really recommended.

[jeromephone 6]

how much would 60 feet of 18/2 cost? seems like it would make trouble shooting easier in the future plus the concern with voltage dorp.

[thewireguys 3]

Yea I would not pull pairs from the Cat6 unless you absolutely have to. You just looking for trouble down the road. Can you pull a second Cat6 to each camera and use it for power?