Hikvision POE powered cameras

haaad

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Hi all,

I am running my HiVi cameras (DS-2CD2185FWD-IS) off POE (ds-7608ni-k2/8p)

Camera has also 12V DC connector for alternative power delivery.

When powered from POE, camera provides 12V on the DC connector.

Does anyone know how much power I can get from camera dc connector?

I cannot trace any datasheet with information on max amps (rather miliamps)

Best regards
HD
 

ludshed

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Not really designed that way. If you put a multimeter to it and are seeing 12v I doubt you’d be able to put any load on it.
 

haaad

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As far as I see it is designed exactly that way. Apparently the voltage is there.
POE pcb provides 12V to camera pcb and 12v can be injected directly yo camera if there is no poe switch available.

POE pcb will have some overhead power I am pretty sure of it. Those are designed to be as universal as possible for selected POE power class. They surley are not redesignig PSU from scratch everytime. And camera module will not necessarily use all of power.
The question is if it is miliamps tens of miliamps (a hundered???).

From camera end point of view, where you have audio in audio out alarm in alarm out... It would be comfortable to provide spare power. In the end POE is about the comfort of data and power on ONE cable.

Anyway. I am setting up a bit of research/testing rig on my old HV poe camera. I should be able to check if I can steal a bit of power to run something on the side.
 

wittaj

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No, it is not designed that way and you will probably blow out the camera board. Maybe not immediately, maybe a few days from now or next week or next month. Just not worth as there are other ways.

The camera is designed to accept power from either the ethernet cable or the 12v cable, but not provide power from one to the other.

Now if you take a reading on the 12v, you will see some voltage (most see like 11.5v or so), but what you're reading is 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.

We have seen a few guys that have opened up a camera and bypassed things to get 12VDC out on that connector, but I would not suggest doing that and risk overloading and ultimately blowing the PoE board in the camera and then you are stuck with a bad camera.

Better to use a splitter and "Y" cable.


 
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TonyR

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+1^^^ THIS!

Inside the cam the incoming POE voltage is fed to a regulator that outputs 12VDC and 5VDC, etc. for the cam's internals. The 12VDC input from the cam's pigtail coaxial connector is tied to the 12VDC output of that regulator but is usually done so with a steering diode that also prevents damage to it and the cam's internal circuitry by an accidental reverse polarity connection to that coaxial connector; IOW, the diode's anode faces the coaxial connector so that it will be forward-biased when the 12VDC is properly connected and allow current to flow INTO the cam, not out. The center of the coaxial connector is positive, the collar is negative.

As stated by @wittaj one could open up the cam and modify it (there's likely another diode on the output of the POE regulator) to get output on that 12VDC connector but IMO I would go the route as suggested with a POE-to-12VDC splitter and a Y-cable.

Your cam, your choice. :cool:
 
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haaad

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As I said - I will test this.
If I blow something... I will repair it. This is not my first rodeo.

It was simple question on how much power I can get...
Instead I had 2 smart... talking about the design like they designed this themself.
Also instead to spot bigger picture and potential - there is only denial of the idea.
Answer could be: you cannot get more than micoamps... (you apparently know the design).
It could be: you would have to short the diode....just make sure POE board provides enough and use the rest.

A bit of simple analisis DS-2CD2185FWD-IS:
Camera: PoE(802.3af, 36 V to 57 V,class 3), 9 W
PD: PoE 802.3af class 3 provides up to 13W

I actually will be testing this on DS-2CD1021-I (my oldie trustie):
Camera PoE: 802.3af, Class 3, 36 V to 57 V, 0.2 A to 0.15 A, max. 6.5 W

One useful post popped in with some technical info while I am writing this TonyR - cheers.
This will be customised design so no need for external dc connector, polarity will not be an issue.

Anyway I appreciate the input.

Best regards
HD
 

TonyR

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As I said - I will test this.
If I blow something... I will repair it. This is not my first rodeo.

It was simple question on how much power I can get...
Instead I had 2 smart... talking about the design like they designed this themself.
Also instead to spot bigger picture and potential - there is only denial of the idea.
Answer could be: you cannot get more than micoamps... (you apparently know the design).
It could be: you would have to short the diode....just make sure POE board provides enough and use the rest.
You joined this forum yesterday and this is your second post, the first one being a 'hello' as a new member, therefore we have no feel for your expertise.

You asked a question and you got an almost immediate, qualifed AND courteous answer.

Sure, it may not have exactly answered your question but it did provide info for a safer, recommended alternative considering the lack of knowing what you could and could not do from a technical standpoint. No one suggested you did not know what you were doing.

You can either accept the suggestion or ignore it...there's no need to act like you were insulted and/or be a general smartass. I read nothing in the reply from @wittaj that merited such a response.

If you come into the forum with a chip on your shoulder I can guarantee that someone will take it upon themself to knock it off.
 

wittaj

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WOW

You asked a question and we politely responded why it won't work based on people trying that exact thing and explaining why you are seeing a voltage - that is not considered a smart @$$ comment - that is considered providing you a real world experience comment. Most would not say my response was a smart@$$ comment...not even easily offended snowflakes LOL

Plus I gave you two work arounds - either take it apart and bypass the diode and risk overloading or a safer option to use an adapter/splitter...HTF is that considered a smart@$$ reply.

A smart@$$ reply would be something like "that won't work stupid".

I think most would agree that explaining why it won't work and the reasoning behind it along with providing two options to accomplish the end goal would be considered an informative reply.

Further, one of the replies was from an installer that has installed millions of dollars worth of cameras. Do you think if this worked that way he wouldn't use it that way in his installs?

Heck we would all use it that way for external mics and IR we added, but guess what, it doesn't work....or at least not for long. And then we lost the ability to power it by POE or 12V.

If you were going to be testing this anyway for kicks and grins, then why even come here to ask if it would work. Try it out for yourself and get the same results those before you have.

Who is the smart @$$...look in the mirror...

Why is it those from the UK seem to be the ones with chips on their shoulders and worse than USA snowflakes LOL.

If you are so smart then why come to a forum to ask questions?

Good luck here on this forum with your attitude...

It is people like you why the ignore feature exists lol
 
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haaad

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I will not be discussing logical fallacies of your posts here.
 

haaad

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Here come the cheerleders with pom poms...
give me - c
give me - o
give me - m
give me - e
give me - d
give me - o
give me - w
give me - n
give me - g
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give me - s
 

Ri22o

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Here come the cheerleders with pom poms...
give me - c
give me - o
give me - m
give me - e
give me - d
give me - o
give me - w
give me - n
give me - g
give me - i
give me - r
give me - s
Is this an anagram?
 

CamFan

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You joined this forum yesterday and this is your second post, the first one being a 'hello' as a new member, therefore we have no feel for your expertise.

You asked a question and you got an almost immediate, qualifed AND courteous answer.

Sure, it may not have exactly answered your question but it did provide info for a safer, recommended alternative considering the lack of knowing what you could and could not do from a technical standpoint. No one suggested you did not know what you were doing.

You can either accept the suggestion or ignore it...there's no need to act like you were insulted and/or be a general smartass. I read nothing in the reply from @wittaj that merited such a response.

If you come into the forum with a chip on your shoulder I can guarantee that someone will take it upon themself to knock it off.
As I said - I will test this.
If I blow something... I will repair it. This is not my first rodeo.

It was simple question on how much power I can get...
Instead I had 2 smart... talking about the design like they designed this themself.
Also instead to spot bigger picture and potential - there is only denial of the idea.
Answer could be: you cannot get more than micoamps... (you apparently know the design).
It could be: you would have to short the diode....just make sure POE board provides enough and use the rest.

A bit of simple analisis DS-2CD2185FWD-IS:
Camera: PoE(802.3af, 36 V to 57 V,class 3), 9 W
PD: PoE 802.3af class 3 provides up to 13W

I actually will be testing this on DS-2CD1021-I (my oldie trustie):
Camera PoE: 802.3af, Class 3, 36 V to 57 V, 0.2 A to 0.15 A, max. 6.5 W

One useful post popped in with some technical info while I am writing this TonyR - cheers.
This will be customised design so no need for external dc connector, polarity will not be an issue.

Anyway I appreciate the input.

Best regards
HD
Haaad,

I have seen the IEEE802 spec. Min power draw by any PD is 10mA. At 37V at PD, that is .37W. So, you missed that key datapoint.

Let's assume it is built to be fully 802.3af compliant. Then the 2CD2185FWD PoE circuit must draw a minimum of .37W and cannot draw any more than 12.95W to be 802.3af compliant.

How much can you draw without affecting the camera is between 0.0W and ?

Spoiler - the exact answer unknown to most people on the planet, except Hikvision engineers or their managers. They don't share that stuff.

Were you hoping to find a Hikvision engineer here?

In any case, I hope this is not for human or property safety purposes, as you will be absorbing all the liability here if something goes bad and your device fails. If it is, then you might want to think about deleting all of this conversation and your user account. Don't want any pesky attorneys (or solicitors as it looks like you are in UK) where you are) looking into why a device failed and happen upon this thread.

If not, you can take empirical measurements and have fun. But do consider circuits change over time (continuous value engineering), so last year's model 2CD2185FWD may deliver where next year's model doesn't.
 

Flintstone61

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It's not even a thing....who needs to run some other shit off the cord? There are zillion ways to get power out there...How about just split the Cat5 pairs and boom, you can get voltage to play with there.
 
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