Sharing one cat5 cable for two cameras (DS-2CD2532F)

[kapios]

After spending an inordinate amount of time trying to snake another cable, I am about to give up. I am trying to install a second camera where a single cat5 cable already exists and would appreciate some assistance. I will not be able to get a second cable at this location nor can I fit a network switch there.

Is it possible to have two cameras connected to a single cable like the attached picture shows?

I want to replace an older cam with two of these: DS-2CD2532F. I will not be using POE for either cam. Can anyone confirm whether this will work?

Any suggestions would be much appreciated.

 

[Brad_C]

After spending an inordinate amount of time trying to snake another cable, I am about to give up. I am trying to install a second camera where a single cat5 cable already exists and would appreciate some assistance. I will not be able to get a second cable at this location nor can I fit a network switch there.

Is it possible to have two cameras connected to a single cable like the attached picture shows?

I want to replace an older cam with two of these: DS-2CD2532F. I will not be using POE for either cam. Can anyone confirm whether this will work?

Any suggestions would be much appreciated.

Yeah, that works. I use it to run a pair of DS-2CD4526FWD-IZ domes over a single cable. Mine *are* both PoE powered from a TP-Link TL-SG2210P switch.

 

[Securame]

That will work.

 

[kapios]

AWESOME! Thank you so much for confirming that this scheme works with these cameras.

I am also surprised to hear that they can be both POE powered using the single cable. Is there anything different/unique in that switch that is able to provide enough voltage to make this work or would any POE injector work? Which pins are used for POE in this case?

 

[Brad_C]

PoE comes in two basic varieties.
Version A sees the power applied over the data pairs. So in your diagram you have 1,2,3&6 used. You get +ve on 1&2 and -ve on 3 & 6.
Version B sees the power on the unused pins so you'd get +ve on 4&5 and -ve on 7&8.

To be standards compliant the device being powered must be capable of both of those. Prior to me picking up a PoE switch, I had a set of hacked up patch leads with 4,5,7&8 broken out and hardwired to a 48V DC PSU. I tossed that when I got a real PoE switch, but it did the job at the time.

In the current case (mine and the one you are proposing) version A would be used as you have no wires on the version B pins.

 

[pozzello]

yup, that'll work. you can also buy such adapters, in case it too much of pain to make your own:
http://www.ebay.com/itm/2pcs-RJ45-Splitter-1-to-2-Adapter-CAT5e-10-100M-ETHA02-/122027912704

 

[Securame]

You said on your first post that you would NOT be using POE.

If you only need data, that will work. If you want to use POE on the same cable, I take back what I said that "that will work" (not saying it will not; I have never tried it).

 

[fenderman]

You said on your first post that you would NOT be using POE.

If you only need data, that will work. If you want to use POE on the same cable, I take back what I said that "that will work" (not saying it will not; I have never tried it).

As brad_c stated, it will work with a standard poe switch using mode a...all standard poe switches use this mode. Midspans generally use mode b.
The only possible issue is interference..

 

[pozzello]

I've done it quite a bit with (mode-A) PoE connections. It works.
have not noticed any interference or crosstalk. twisted pair seems to take care of that.
if using adapters (rather than making your own specially terminated cable),
you'll need 4 extra patch cables to make the connections.

 

[kapios]

THANK YOU for the very useful info! There is another location where I am considering adding a camera, so knowing how I can accomplish sharing data and power over one cable is great.

Hopefully this post helps someone in the future that is stuck in the same predicament.

 

[Q™]

Murphy's rule of cabling: If you need 1 cable, run 4!

 

[yeme]

Thank you posting this!

I am about to install a fifth camera and this will save me a lot of work. I was unaware of the two types of POE and the way the power was transmitted over the cable.

 

[Defender666]

I cannot confirm that poe would work with 1,2,3,6
In my experience using the 4 cables for an additional LAN will break POE function because in general power runs always through 4,5 and 7,8 so if you use for second lan no more POE.

 

[Q™]

 

[pozzello]

Q, that's for mode-B (typically midspan injection).
Mode A uses the same as the data pins, so IT WORKS to put two data/poe runs on one run with a Mode-A Poe Switches (as most switches are)
Why are people saying this doesn't work when clearly it does? I've done it a bunch. I'm using it right now.
Yes, if you've got mode-B poe, it will not work, but that's a separate thing from T568A vs T568B (which is just a color-coding scheme)

 

[Brad_C]

Why are people saying this doesn't work when clearly it does? I've done it a bunch. I'm using it right now.

Typically on any forum there are a small group of people who are experts. They generally know how everything works and are happy to let everyone know at every opportunity even when faced with irrefutable evidence to the contrary. Those who really know just shake their heads, but unfortunately they sow the seeds of doubt in the minds of those that have come to seek advice and generally cause confusion. It is what it is. You can try and correct them until you are blue in the face, but it is generally a waste of effort.