Two POE cameras (most likely Dahua or Andy) off one ethernet cable - best method

saltwater

Getting comfortable
Joined
Oct 6, 2019
Messages
336
Reaction score
328
Location
Melbourne, Australia
What are my options if I want to connect two POE cameras, most likely Dahua type, to one ethernet cable? At the camera location I do not have access to normal power. I have run two ethernet cables, but now I'm considering two cameras per ethernet cable.
 

ccssid

Getting the hang of it
Joined
Jan 2, 2022
Messages
43
Reaction score
65
Location
us
In for the ride. I do know a coupler will work for a single line with Poe. A splitter will work for your situation...but...not sure about the transfer of bandwidth ( possible degradation), and same issue perhaps with Poe.
 

TonyR

IPCT Contributor
Joined
Jul 15, 2014
Messages
11,311
Reaction score
23,549
Location
Alabama

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
14,734
Reaction score
27,342
Location
USA

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
14,734
Reaction score
27,342
Location
USA
^You have to be careful with couplers like that (notwithstanding the concerns about if used outside and exposed to elements, etc.) as they do sell one's that are "splitters" that look like that, but you can only use one side or the other, not both at the same time.

The two that I mentioned above work very well with cameras and are not an issue splitting one run into two. You do need to have available POE though for either one.
 

ccssid

Getting the hang of it
Joined
Jan 2, 2022
Messages
43
Reaction score
65
Location
us
^You have to be careful with couplers like that (notwithstanding the concerns about if used outside and exposed to elements, etc.) as they do sell one's that are "splitters" that look like that, but you can only use one side or the other, not both at the same time.

The two that I mentioned above work very well with cameras and are not an issue splitting one run into two. You do need to have available POE though for either one.
I found myself wanting to relocate an indoor camera and being too lazy I tried this coupler to extend my Ethernet line to my Poe camera....it works!!!!. Every day , when I walk into my basement dungeon, I can see the coupler doing it's job. One day , maybe, I will change out to the proper length cable. And yes, not for outdoor usage
 

tigerwillow1

Known around here
Joined
Jul 18, 2016
Messages
2,876
Reaction score
5,816
Answering at the 30,000 foot level, there are two obvious options, with examples of both already posted:

1. A poe powered 2 (or more) port ethernet switch.
2. A splitter-combiner set that places a 2nd ethernet channel on the otherwise unused 4 wires of an existing ethernet link.

Option 1 is a bit simpler to hook up, saves a port on your POE switch, but requires that port to power 2 cameras and the poe powered switch. The single port must be capable of powering both cameras.

Option 2 works the same as if you has run 2 ethernet cables, with added connection complexity on both ends. In general, works only with POE switches, not injectors, because injectors tend to use all 4 pairs on the ethernet cable. Also not usable with POE++ which also uses all 4 pairs.

I've used both. They both work. Some people think that running 2 links on a single cable compromises data integrity. I've not seen any hints of that in my system.
 

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
14,734
Reaction score
27,342
Location
USA
I've used both. They both work. Some people think that running 2 links on a single cable compromises data integrity. I've not seen any hints of that in my system.
Using that same ill-conceived logic that running two links on a single cable compromises data integrity...how do we explain 8 cameras going to an 8-port switch and then one cable (not 8 cables) going to the computer....Every system at some point has a lot of devices going thru one cable....as long as the rated capacity of all of the peripherals is higher than the demand of all of the devices, all is good...

Of course at some point there may be an issue, but these are designed to carry that data. The first one I linked you can even daisy chain it for more deployment. The 2nd one not at all. Both serve a purpose, but the flexibility of the first one is nice.
 

tigerwillow1

Known around here
Joined
Jul 18, 2016
Messages
2,876
Reaction score
5,816
Using that same ill-conceived logic that running two links on a single cable compromises data integrity..
I think you interpreted something other than what I meant to say. The alleged data integrity issue I mentioned is based on physical crosstalk between two independent 2-pair links routed on a single 4-pair cable. In has been brought up on other splitter-combiner discussions, so I figured I may as well mention it up front here.
 

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
14,734
Reaction score
27,342
Location
USA
OK that makes sense. But yea, like you, I have never seen issues with these two devices.

But I am aware of some that are cheaper that either do not work as intended (can only use one of the dual ports at a time) or they have other issues.
 

Mike A.

Known around here
Joined
May 6, 2017
Messages
2,460
Reaction score
3,380
Speaking of cheaper ones, I've used a couple of these for a while now without any problems. They had a $5 off coupon before and easily returnable so were worth a try at $13.


Clearly not made for any unprotected outdoor use.
 

saltwater

Getting comfortable
Joined
Oct 6, 2019
Messages
336
Reaction score
328
Location
Melbourne, Australia
Thanks everyone, all useful info and I'm now good to go with my project.

I've got two ethernet cables at my letterbox. I've been thinking more about purpose LPR, especially at night but didn't like the fact, at night, everything else, except the number plate is dark. I'd still like an overview, and thus is why I asked about two cameras off one ethernet cable.
 

Smilingreen

Known around here
Joined
Sep 17, 2021
Messages
2,437
Reaction score
9,716
Location
USA
What are my options if I want to connect two POE cameras, most likely Dahua type, to one ethernet cable? At the camera location I do not have access to normal power. I have run two ethernet cables, but now I'm considering two cameras per ethernet cable.
What is the total length of a single run? Would the cable for 2 runs and 4 RJ-45 connectors be cheaper than buying an adapter, buying a weather proof box to put it in, the weather proof cord grips? CAT5e cable isn't very expensive, IMHO.
 

saltwater

Getting comfortable
Joined
Oct 6, 2019
Messages
336
Reaction score
328
Location
Melbourne, Australia
What is the total length of a single run? Would the cable for 2 runs and 4 RJ-45 connectors be cheaper than buying an adapter, buying a weather proof box to put it in, the weather proof cord grips? CAT5e cable isn't very expensive, IMHO.
Yes, cable is cheap, but would be too expensive to lay additional cables to be concealed in walls. The single run is about 30m. Yes, if I had my time over again during the house build I would have laid 4 cables. I did actually lay 3 cables but one is now earmarked for my water irrigation controller.
 
Top