POE for illuminator

B

Beaglehome

n3wb
May 11, 2018
3
0
I'm new to this so please be gentle!

I am looking to install illuminators with some of the installed cameras and would like to power them via POE.

The NVR is a Hikvision DS-7616NI-12/16P and the datasheet doesn't specifically mention POE+ but quotes a maximum total 200W from the POE across all cameras and supports standard IEEE 802.3 af/at

The cameras concerned are 30-50 ft cable run and are POE. They are rated at 7w max and draw about 5w. The illuminator I have is rated at 18 watts.

This would give a total power of 23-25w per camera/illuminator combination.

After adding the illuminators to total power draw on the NVR would be only ~100 w - well short of the total rating

Questions...
1. Is it feasible to use POE to power this combination of cameral and illuminator?
2. If so, and advice?
 
Technically speaking, PoE splitters are usually rated at two amps which means 24 watts. Experience has shown that two amp rating to be just a "tad" optimistic. I would suggest pulling a CMR rated 18/2 cable, 16/2 for longer runs, to supply power for an IR illuminator. No question that will work and work well.
 
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sebastiantombs said:
Technically speaking, PoE splitters are usually rated at two amps which means 24 watts. Experience has shown that two amp rating to be just a "tad" optimistic. I would suggest pulling a CMR rated 18/2 cable, 16/2 for longer runs, to supply power for an IR illuminator. No question that will work and work well.
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Not sure I understand what you are suggesting here. The CAT5/6 cable is 30-50 ft. The 12 volt cable from the splitter would be only 3-5 ft so I would expect the voltage drop from the splitter would be minimal. I guess, I would restate the question. ..

Given that I am not overloading the total power of the NVR, would there be a problem for the camera or NVR with 23-25 watts drawn at a single splitter setup like the photo 105437 shows?
 
Contadino said:
I'm interested in this also. Could I use BlueIris to detect motion and then turn on a visible light floodlight that is on a separate POE wire? Could a NVR do this?
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A NVR's alarm output could possibly do that; of course, you'd need an external relay to interface properly and handle the voltage & wattage requirements of the flood.

Blue iris can send an HTTP command upon motion detect and close a Shelly1 Wi-Fi relay to turn the lamp on as well. Although the Shelly1's relay output is a "dry" contact and is rated to switch up to 15A @ 120VAC, I personally would have it operate an external relay or contactor to switch the line voltage lamp.

I wrote this article to describe how BI can receive input and provide output using the Shelly1; the section on "OUTPUT" could be modified to have BI detect motion and close a relay ==>> Simple Blue Iris I/O using Shelly1 Wi-Fi Devices

Either way, know that a lamp switching on in the night can blind a cam for few seconds until the cam can adjust, it may possibly miss some valuable action during that period. Many here leave select visible LED floods on all night and some cams will respond with full color depending on their image sensor's ability.
 
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As I said, PoE splitters are rated for 2 amps or 24 watts, nominal. Unfortunately that rating is usually on the optimistic side and under full load conditions, camera and IR running and approaching 24 watts or exceeding even 20 watts, may overload the splitter. Given that the splitters are not, shall we say made, to the highest quality standards there may be some un-intended results.

When I said length being longer it was in reference to using a dedicated 18/2 or 16/2 cable to supply 12 volts for the IR illuminator. PoE will work out to 100 meters. The length of the cable from a PoE splitter to the devices should have no significant impact at all.
 
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Beaglehome said:
Thanks. That's exactly what I intend to do. My main concern is that the power demand of the illuminator and camera is too large for an individual POE supply from the NVR
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I'm running a Ubiquiti PoE switch and it handles all of my locations... Two of which have a 20-watt IR and Dahua 5442 camera.
 
sebastiantombs said:
As I said, PoE splitters are rated for 2 amps or 24 watts, nominal. Unfortunately that rating is usually on the optimistic side and under full load conditions, camera and IR running and approaching 24 watts or exceeding even 20 watts, may overload the splitter. Given that the splitters are not, shall we say made, to the highest quality standards there may be some un-intended results.

When I said length being longer it was in reference to using a dedicated 18/2 or 16/2 cable to supply 12 volts for the IR illuminator. PoE will work out to 100 meters. The length of the cable from a PoE splitter to the devices should have no significant impact at all.
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I've tried running one at 2amps...it got really hot. I wouldn't trust it to not burn my house down.

I bought a handful of them from Aliexpress and some of the more expensive ones from Amazon. The ones from Amazon were built better. They had a transformer in them and the others... Im not sure what circuitry they use to step the voltage down.
 
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I would guess they use a buck converter rather than a transformer, which would need an inverter, transformer rectifier and filter. Way too many component and way to lossy. They will get hot under load though.
 
sebastiantombs said:
I would guess they use a buck converter rather than a transformer, which would need an inverter, transformer rectifier and filter. Way too many component and way to lossy. They will get hot under load though.
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Hmm I'll have to make a separate thread with some pictures of my findings. The Amazon ones were more efficient by a couple watts or so according to the load on my switch. It also ran cooler. I'm assuming that's where the extra power was going, heat...

I'll probably get a 15v power supply to drive the big IR lamp I was trying to drive over POE. By the time it gets to the light it will be down to around 12v.
 
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