Feed two PoE cameras with one network cable

bp2008

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Yeah I considered it, but I'd need a bigger box outside too, and the ambient temperature for those boxes would exceed both extremes every year, particularly on the low end all winter long. Plus the cameras being fed by that end of the house don't have a remote power cycle mechanism in case they go unresponsive.
 

gmaster1

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Yeah I edited the post too slowly -- I replied to that bit about temperatures. The bigger box though is an issue. Unless you had the switch on the inside of the garage/house and only ran both Ethernet lines outside into that white box.
 

bp2008

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Ah, yes.

Thing is, I used the last of my cable spool a long time ago. So I could spend probably $70+ on a new spool, or $50+ on a new weatherproof enclosure and a poe-powered switch to go in it.

Also have to drill a new hole in the floor of my back closet if I run another cable.
 

tigerwillow1

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I've been running 2 links on one cable for a few months and haven't noticed any problems or issues. I didn't use any commercial splitters, instead building 3-headed cables myself. I've tried RJ45 males, and keystone punch-down females at the end with all 8 wires. Both work. I try to keep the number of connectors down as much as it's feasible.
 

bp2008

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You mean you are sharing wires with multiple devices? I find it hard to believe that would work at all. I'm just redirecting 4 of the wires to one jack and the other 4 wires to another jack.
 

bp2008

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Hmm, something about 3-headed cables suggested you were using one cable for 3 devices :) But now I understand, you were just building the adapters with one female and two male RJ45.
 

bp2008

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I believe the reason I didn't notice a problem to start with is that I was only pulling one stream from each camera. Eventually I started pulling a second stream for a backup BI box that continuously records. Then I started pulling a third stream for 24/7 live display on a dedicated monitor. As bandwidth usage went up, reliability went down.
 

cuz

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If I understand correctly you have to use the cable sharing technique if you want to be able to plug both cameras into the dedicated POE ports on the back of the NVR, is that right? I didn’t think the NVR would recognize more than one camera per port on that side.
The 1x4 splitter/sharer mentioned in earlier posts is a switch that would need to be connected to the NVR through its other network port which would put the cameras from that switch on your home network.

Can anyone confirm that?
 

fenderman

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If I understand correctly you have to use the cable sharing technique if you want to be able to plug both cameras into the dedicated POE ports on the back of the NVR, is that right? I didn’t think the NVR would recognize more than one camera per port on that side.
The 1x4 splitter/sharer mentioned in earlier posts is a switch that would need to be connected to the NVR through its other network port which would put the cameras from that switch on your home network.

Can anyone confirm that?
You would have to split both sides...dont do it...run 2 cables.
 

cuz

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fenderman

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cuz

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That is a mess.check for dropped packets. Much better off using a Poe powered switch for a few bux more
If I used the switch, then I wouldn’t be connecting the cameras to the dedicated Poe ports on the NVR. I prefer to have them isolated that way.

I didn’t think a few dropped packets was a big deal for streaming surveillance video. In any case, I expect it to be a temporary thing anyway.
 

fenderman

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If I used the switch, then I wouldn’t be connecting the cameras to the dedicated Poe ports on the NVR. I prefer to have them isolated that way.

I didn’t think a few dropped packets was a big deal for streaming surveillance video. In any case, I expect it to be a temporary thing anyway.
What is the point of having the cameras "isolated" if the NVR which is just as vulnerable is not? There are much better ways to isolate everything. Dropped packets is a huge deal for video surveillance. You have it backwards, its not a big deal for other things like buffered internet streaming.
 

cuz

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What is the point of having the cameras "isolated" if the NVR which is just as vulnerable is not? There are much better ways to isolate everything. Dropped packets is a huge deal for video surveillance. You have it backwards, its not a big deal for other things like buffered internet streaming.
Thanks, it wouldn’t be the first time I’ve gotten the facts backwards. Appreciate the recalibration.
 

PoppyAnn

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I have been looking at running 2 network cameras via one cat 8 cable but as the cameras are 48 volt poe which use the 4 wires to send the power down how many wires do the cameras require to send video down the cameras are 4K cameras I thought the cameras used 4 wires for video and 4 wires for power which would only allow 1 camera down one cable am I incorrect?
 

DsineR

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I have been looking at running 2 network cameras via one cat 8 cable but as the cameras are 48 volt poe which use the 4 wires to send the power down how many wires do the cameras require to send video down the cameras are 4K cameras I thought the cameras used 4 wires for video and 4 wires for power which would only allow 1 camera down one cable am I incorrect?
Here's a good capture showing POE Mode A & B pinouts, as related to PDs & PSEs.
If you are cabled direct from a POE switch (Endspan) to your camera, you are using Mode A pinout. This sends POE power over the same pins (1,2,3,6) that carry data, leaving pins (4,5,7,8) unused.
poe.png
 

bp2008

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I have been looking at running 2 network cameras via one cat 8 cable but as the cameras are 48 volt poe which use the 4 wires to send the power down how many wires do the cameras require to send video down the cameras are 4K cameras I thought the cameras used 4 wires for video and 4 wires for power which would only allow 1 camera down one cable am I incorrect?
I apparently never updated this thread earlier, but I ended up installing a larger junction box with one of these inside as gmaster had recommended, and it worked fine for several years until I sold that house and moved away last year. I used a PoE+ switch as a power source, and had this feeding 3 cameras with just one cable going outdoors.

If I was to start over today, I would just get one of these which is outdoor rated without the need for a separate enclosure, and has higher power capacity too. I'd try to power it with an 802.3bt-compliant switch or injector like this one.
 
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