Powering IR illuminators with camera DC connector: How many watts?

CanCuba

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After seeing this post:


I'm really curious about running an 8 or 12 watt IR illuminator directly off the DC connector on the cameras. Seems much more efficient than another method I was considering.

Tested the voltage on the DC connector on a POE camera today and got 11.5v Less than ideal but it may work.

Big question is: How many watts can we pull off said connector? Is it camera dependent? I run all Dahua hardware.
 
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If you mean the DC connector that is attached to the camera, itself, you're reading voltage leaking through the diode that is there to prevent drawing power from that connector. The PoE converter in the camera is designed to support the camera only and no external devices.

If you want to do that, and keep in mind that if you're talking a PT camera, the switch port will definitely need to be PoE+ to handle the additional loading. A PoE+ splitter and "Y" cable can make that possible. I've done that myself, but have discontinued using splitters and just pull a CMR rated 16/2 cable along with the network cables. Much more robust.

Here's a few links for you -

Y Cable

PoE Splitter

PoE Splitter/Extender
 

CanCuba

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If you mean the DC connector that is attached to the camera, itself, you're reading voltage leaking through the diode that is there to prevent drawing power from that connector. The PoE converter in the camera is designed to support the camera only and no external devices.

If you want to do that, and keep in mind that if you're talking a PT camera, the switch port will definitely need to be PoE+ to handle the additional loading. A PoE+ splitter and "Y" cable can make that possible. I've done that myself, but have discontinued using splitters and just pull a CMR rated 16/2 cable along with the network cables. Much more robust.

Here's a few links for you -

Y Cable

PoE Splitter

PoE Splitter/Extender
This is exactly what I was originally planning. I'm in the process of installing splitters/extenders to save running new cables. I have to run all my cabling outside in conduit (all brick/cement construction) about 20 feet off the ground.

The post I linked in my OP piqued my interest. But he's also running Hikvision so maybe they allow a draw off of the DC connector while using POE.
I've found these:


Living in a hot climate, this keeps the actual electronics inside by the NVR and outside is just a simple Y adaptor. I'm worried about something outside in a box running hot and failing.

Thanks for clearing that up for me.
 
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I've seen a few guys that have opened up a camera and bypassed things to get 12VDC out on that connector. In good conscience I can't recommend doing that because of the risk of overloading, and ultimately blowing the PoE board in the camera. Better to use a splitter and "Y" cable.
 

tigerwillow1

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I've seen a few guys that have opened up a camera and bypassed things to get 12VDC out on that connector. In good conscience I can't recommend doing that because of the risk of overloading, and ultimately blowing the PoE board in the camera. Better to use a splitter and "Y" cable.
As one of those running about a dozen bypassed cameras, I'll answer a couple of the OP's questions:

How many watts can we pull off said connector? 4 watts, with the camera's own IR illumination shut off.

Is it camera dependent? Hard to answer that without having tested every camera model. What I can say is that I'm running camera-powered external IR illuminators with 7 different Dahua models, and the voltage from the POE circuitry starts tapering off when the added load goes much above 4 watts.

As sebastiontombs mentioned, that 11.5 volts you're seeing is what's leaking through a diode in the reverse direction, as read by a high impedance meter. Put any meaningful load on it and it drops to zero. I run a few 8-watt external illuminators, and use a POE splitter with them. I remember seeing a few months back that some newer cameras have an intentional 12 volt output, but it's very low power, probably to power a microphone I assume.
 
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