Mains 240v cable to 12v microphone

[Mikefromlondon]

Microphones only ever draw miliamps, as they only need a few miliamps to run a pre-amp, so it would hardly impose any loading on POE, using a 3pin 12v regulator drawing just a few mili amps is not even going to be noticeable to POE

 

[Lectrician]

The camera spec will be 12 V dc on separate terminals, or POE. The POE 802.3af is actually about 48 volts and the 12 volt microphone cannot be connected directly to the POE supply.

Completely agree. It says it is 802.3af compliant (so PoE 48v), OR 12v DC if powered via its DC inlet, not the PoE.

 

[OwainDIYer]

1. Use a converter like this to bring the voltage down and wire the microphone straight into this
2. Use a passive microphone which doesn't need dedicated power (likely option)

Next is to see if I want to hook a speaker up too

2. That converter has exposed mains terminals and must be fitted into an enclosure

3. You can only use a passive microphone which doesn't need power if the camera supports it. I couldn't see any mention in the manual of that camera about mic/speaker connections.

 

[Mikefromlondon]

OP, your own suggested solution i.e. using mains to power up the Mic via a tiny 3VA to 6VA Transformer style power supply, that provides a 12v DC output. Your mains has already been wired to your porch for the porch lights etc, and the camera lighting, the Mic can be powered using a small separately housed 12v DC 250mA power supply adaptor, that you will need to tuck in somewhere safely, and wire its mains input to your incoming 230v somewhere in the porch, this can be the ceiling rose, or some suitable junction box well protected, the adaptor itself must be protected by a small fuse such as 100mA time delay (anti-surge) fuse to protect wiring against any possibility of adaptor going faulty, most adaptors are internally protected with a small fuse on board, keep it simple and you need not worry about interfering with your POE network power as it may cause other problems to video signals and so on, just look for a small 12v dc power supply and wire it to incoming mains, use a terminal strip that you can house both the adaptor and the strip in a small ABS box. That is the route I would take.

 

[aab203]

3. You can only use a passive microphone which doesn't need power if the camera supports it. I couldn't see any mention in the manual of that camera about mic/speaker connections.

3. It supports it as far as I am aware (have also looked on other forums). It supports LineIn and MicIn.
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Is another option to T off the mains cable; One part goes to the PIR/lighting and the other is just wired to a normal socket, which I can plug in a 12v adapter like this. This socket would be housed within the floorboards and the 12v cable (from the adapter) would be fed through the external wall into the porch ceiling void?

 

[ban-all-sheds]

This socket would be housed within the floorboards

Screwed joints should be accessible.

 

[aab203]

It would be as the floorboard access is near the front of the room (i.e. closest to the external wall where the porch roof is attached to) and its just got carpet on top - easy enough to pull back if required