Two POE Cams Over One Ethernet Cable

rfj

Getting the hang of it
Joined
Oct 26, 2014
Messages
297
Reaction score
88
I installed a second cam this weekend using this adaptor. I can see both PoE cams in BI and has been working fine so far. We will see how long it lasts as it is outdoors. I am thinking of getting a second one instead of those "protected/outdoor" versions that cost like 3x.
I ended up buying 3 more from Ebay. Now I need to buy more good cameras... Linovision PoE Extender Passive 2 Port 802.3af/at, FREE SHIPPING | eBay
 

bradner

Getting comfortable
Joined
Aug 15, 2019
Messages
377
Reaction score
647
Location
PNW
I installed a second cam this weekend using this adaptor. I can see both PoE cams in BI and has been working fine so far. We will see how long it lasts as it is outdoors. I am thinking of getting a second one instead of those "protected/outdoor" versions that cost like 3x.
Those have lasted me over 2 years in the wet pacific northwest so far....
 
  • Like
Reactions: rfj

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
13,372
Reaction score
24,925
Location
USA
Do you know whether I can use a NVR instead of POE switch, in order to split one cable to two cameras?
NVR model: Dahua NVR4108-8P-4KS2 (which supports POE)
In most instances, the NVR will only accept one camera per POE port. But give it a try as some have had success doing it with this splitter. But some haven't. Seems to be hit or miss. It works for my neighbor.
 

Donut17

n3wb
Joined
Dec 20, 2019
Messages
7
Reaction score
1
Location
Kentucky
Not sure how I missed this thread but thanks to all that have contributed. This will save me much blood, sweat, and tears running more cables in my attic.
Do you all think the splitter from Nellysecurity would be better suited to handle higher temperatures of a detached garage or attic?
 

rfj

Getting the hang of it
Joined
Oct 26, 2014
Messages
297
Reaction score
88
Not sure how I missed this thread but thanks to all that have contributed. This will save me much blood, sweat, and tears running more cables in my attic.
Do you all think the splitter from Nellysecurity would be better suited to handle higher temperatures of a detached garage or attic?
Depends!!! I am no expert in this at all but I suspect that on the outside those Nellysecurity switches are probably just switching the path of connectors, i.e. no chips are involved. If that is true, then they should be less affected by hot or cold temperatures (humidity is a different story). For something like the LinoVision the temperature is -30 - 65 degrees Celsius at the usual 10-90% humidity . See here on page 2
I am preferring the LinoVision despite the fact that I struggle a bit to put them into a junction box but I don't like the fact that the other solution is either taking up two PoE ports (or maybe you can get away with a PoE injector which is more equipment 'hanging' around).
 

rfj

Getting the hang of it
Joined
Oct 26, 2014
Messages
297
Reaction score
88
Thinking about it, why does the solution with the cable splitter require two PoE ports? The signal from the two cameras is transferred over just 8 conductors. So why do they have to be taken apart? The solution that requires only one PoE port can do it. I guess some kind of processing must be happening. And how does the switch know anyways that there are two cams on one port?
 

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
13,372
Reaction score
24,925
Location
USA
Thinking about it, why does the solution with the cable splitter require two PoE ports? The signal from the two cameras is transferred over just 8 conductors. So why do they have to be taken apart? The solution that requires only one PoE port can do it. I guess some kind of processing must be happening. And how does the switch know anyways that there are two cams on one port?
The one that I linked that only needs one POE port has some processing inside and pulls a little power from the POE to run it.

The cable that requires two ports does not have that processing. For kicks I tried it without plugging it into the 2nd POE and the camera didn't work.
 
  • Like
Reactions: rfj

tigerwillow1

Known around here
Joined
Jul 18, 2016
Messages
2,735
Reaction score
5,403
Thinking about it, why does the solution with the cable splitter require two PoE ports? The signal from the two cameras is transferred over just 8 conductors. So why do they have to be taken apart? The solution that requires only one PoE port can do it. I guess some kind of processing must be happening.
The splitter solution is the electrical equivalent of running 2 separate ethernet cables for non-gigabit connections. 2 separate cables would of course use 2 POE ports. There are 2 separate data streams from the cameras to the POE switch. The one port solution is actually an ethernet switch that combines the data from 2 cameras into a single data stream, which can then be connected to a single POE port. So yes, processing is happening.
 
  • Like
Reactions: rfj

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
13,372
Reaction score
24,925
Location
USA
It is definitely a tight fit. For the 2nd one, I ended up making my own junction box just to give it more room.
 
  • Like
Reactions: rfj

rfj

Getting the hang of it
Joined
Oct 26, 2014
Messages
297
Reaction score
88
How did you do that? I did go to home depot today and bought some 4" ABS pipe. It's about 4mm 1/6" too wide (you can see the rim in box2.png). I would also have to create some adaptor plate for the top so I can secure the camera and another adaptor plate at the bottom so I can mount the thing to the wall.
 

Attachments

wittaj

IPCT Contributor
Joined
Apr 28, 2019
Messages
13,372
Reaction score
24,925
Location
USA
It was a box - something like this from Home Depot and then I screwed the camera into this top.

1655091427833.png
 

rfj

Getting the hang of it
Joined
Oct 26, 2014
Messages
297
Reaction score
88
Ah, so you just used a square box. That's probably the easiest. Drill a few holes and done.
 

d5775927

Getting the hang of it
Joined
Dec 11, 2019
Messages
167
Reaction score
70
Location
here
I ordered one of these (~5$):
I checked it today (for a minute) on the NVR end (to avoid remounting the IPCs), seems to work fine with two Dahua IPCs (2431TM-AS-S2 && 5442-ZE).
Works like this:
1656883407382.png
Eventually, when splitting one cable into two, the NVR end will have two male cables (which is good for us, with regards to IP and POE).
 

john38119

n3wb
Joined
Jul 16, 2022
Messages
1
Reaction score
0
Location
usa
The camera will get its power over either the blue+brown pairs OR the green+orange pairs, depending on which mode is provided by the power source. In the majority of cases, a POE switch sends the power over the green+orange pairs, and the blue+brown pairs are unused in the ethernet cable. POE injectors usually send the power over the blue+brown pairs.
If I test a Lorex NVR for which pairs are carrying power, I should be able to make my own adaptors, correct ?
 

tigerwillow1

Known around here
Joined
Jul 18, 2016
Messages
2,735
Reaction score
5,403
If I test a Lorex NVR for which pairs are carrying power, I should be able to make my own adaptors, correct ?
Not having a built-in POE switch in my NVR I should be careful about assumptions, so I'll say I'd expect that the NVR would use POE mode A, with the blue an brown pairs unused. I've made my own adapters, and also used purchased adapters. The purchased ones look better as the ones I make have a keystone jack hanging on 4 loose wires.
 
Top