Can the brown and green wire of the Alarm Out from the Dahua camera be used for a 12V power supply for microphone?

[zexoni70]

Hello,
as for the side of the house where my IPC-HFW3841T-ZAS camera is installed, which does not have a built-in microphone, and I do not have a power outlet and I can not stretch an additional LAN or power cable, I would ask an unusual question:

Can I use it the brown and green wire from the Alarm Out from the Dahua IPC-HFW3841T-ZAS camera be used for a 12V power supply for the Dahua HAP201 microphone?

Attached are pictures from the connection and specifications, so tell us your opinion...

 

[fenderman]

Hello,
as for the side of the house where my IPC-HFW3841T-ZAS camera is installed, which does not have a built-in microphone, and I do not have a power outlet and I can not stretch an additional LAN or power cable, I would ask an unusual question:

Can I use it the brown and green wire from the Alarm Out from the Dahua IPC-HFW3841T-ZAS camera be used for a 12V power supply for the Dahua HAP201 microphone?

Attached are pictures from the connection and specifications, so tell us your opinion...


View attachment 129880View attachment 129881View attachment 129882View attachment 129883View attachment 129884

No. But the ethernet cable coming to your camera has 2 unused pairs.

 

[zexoni70]

No. But the ethernet cable coming to your camera has 2 unused pairs.

How do I find out what the colors are and what those two unused wires are, and does that mean I have to insulate those two wires and not put them on both sides in RJ-45 connectors when I crimp them again?

 

[zexoni70]

How do I find out what the colors are and what those two unused wires are, and does that mean I have to insulate those two wires and not put them on both sides in RJ-45 connectors when I crimp them again?

ie. how exactly to find out which two wires are not used in LAN cables because my cameras are powered from a gigabit Switch ...?

 

[aadje93]

No. But the ethernet cable coming to your camera has 2 unused pairs.

Dear Fenderman, the switch decides what pairs to use for power depending on the appliance used, it could be mode A or B for POE, so all 8 could be randomly used with a camera.

Most 100mbps connections will use mode A, this is power over the 2 data pairs used for 100mbps, so you have a none-poe 100mbs line spare (as 100mbps uses only 2 of the 4 pairs, you could split 1 cable into to seperate 100mbps lines, works great for IOT stuff which work on solar but like hard-wired connection, there are even "UTP splitter" boxes that do this for you instead of making a hacked cable yourself with dual connectors)

but Mode B is the other option, then the unused pairs will be power source, so the data cables dont run the POE, and then all 4 pairs are needed for the appliance.

Finally we have 4PP mode, there all 4 pairs will transfer power, this is the POE++ stuff, which a ipcam wont need, but mostly high end wifi accespoints use or wireless bridges on the >5GHZ network (ptp wireles, ubiquitie/mikrotik stuff for example)

But personally with POE i wouldn't "hack" the cable to do a double job, there is a risk of short circuit in the switch, pulling the whole camera system down, or breaking the camera/cables due to to much power draw (Camera negotiates POE, but the external appliance will start drawing more power)

 

[fenderman]

@aadje93
I am familiar with mode a and b as you can see in this post back in 2017. My point was that it is doable if he for whatever reason he cannot run more cable.

What POE mode (A or B) does Dahua PoE NVR use?

Does anyone know what POE mode Dahua uses ? is it alternative A or B? I'm having a problem where 1 of the cameras that's hardwired to the exterior, it doesn't work when it connects to the Dahua POE NVR. But when I use a TP-Link PoE injector, it works. When I bring the camera into the house...

ipcamtalk.com

There is no risk of the mic drawing too much power. Of course the best solution is to run a new cable.

 

[N-i-k-s-o-n]

You can use a PoE splitter to split the incoming PoE line into Ethernet and 12V to power the camera and microphone.

 

[zexoni70]

You can use a PoE splitter to split the incoming PoE line into Ethernet and 12V to power the camera and microphone.

How, when the voltage from 48V from the Switch to the camera is already passing through the LAN cable ...?

 

[N-i-k-s-o-n]

PoE splitter is just for this purpose. It includes standard PoE, and at the output you get Ethernet and 12V 1A.
Here is an example from Amazon:

https://www.amazon.com/ethernet-Splitter-Compliant-Surveillance-ipolex/dp/B078LYW6D7?th=1

A PoE splitter is just for this purpose. It includes standard PoE, and at the output you get Ethernet and 12V 1A.
Here is an example from Amazon:

You will also need a power splitter type 1 input - 2 outputs (to power the camera and microphone)

 

[Broachoski]

PoE splitter is just for this purpose. It includes standard PoE, and at the output you get Ethernet and 12V 1A.
Here is an example from Amazon:

https://www.amazon.com/ethernet-Splitter-Compliant-Surveillance-ipolex/dp/B078LYW6D7?th=1

A PoE splitter is just for this purpose. It includes standard PoE, and at the output you get Ethernet and 12V 1A.
Here is an example from Amazon:

You will also need a power splitter type 1 input - 2 outputs (to power the camera and microphone)

The type 1 input - 2 outputs splitter that N-i-k-s-o-n mentioned needing is shown at the bottom of this photo of a Microseven IP mic.

It is needed because the PoE splitter removes the 48v from the cable and converts to 12v via the 2.1mm jack so you will need to feed 12v to the camera jack as well as the mic.

 

[tigerwillow1]

There are splitters that pass the power through on the ethernet line to the camera. They simplify the wiring but cost more. Maybe they're worth it, maybe not. Here's one example:
Tycon PoE-MSPLT-4812P Mini Splitter 802.3AF -AT or passive 48 PoE Input, 12VDC 15W Output

 

[zexoni70]

Thanks to everyone for the suggestions!

As I live in Serbia and as much as I searched on google, I don't have to buy most of those things in my country!
However, I will then think about the cheapest and most cost-effective option to install another UTP LAN cable and just use two POE passive splitters that I have from before, and buy another 12V DC for the microphone ...

Thanks and regards!