Passive POE

Stanley71

Getting the hang of it
Aug 26, 2017
144
17
USA
Can a passive POE device/switch be used to power Hikvision cameras? Like the devices from WiFi Texas and a few others. Something about passive vs af standard I don’t unite understand. Good and bad of passive. Thanks
 
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The difference between passive and active PoE is the auto negotiation. Active devices do a handshake between the Power Supplying Equipment (PSE) and the Powered Device (PD) before it turns on the power. Passive is always on. It’s all about the right tool for the job.

The big benefit of active is not having to think about what you plug in. We recommend active PoE PSE in cases where you might plug something non-PoE into a port by accident, like by your office desk, or the PD requires it, like Cisco WAP’s. There are active PoE injectors if that fits your application: All Products

The benefits of passive PoE are simplicity, reliability, and affordability. In a case like PoE cameras, the passive injectors work great, and Darwin awards go to people trying to plug a laptop into the port on the ceiling and unplugging a PoE camera.
 
The benefits of passive PoE are simplicity, reliability, and affordability. In a case like PoE cameras, the passive injectors work great, and Darwin awards go to people trying to plug a laptop into the port on the ceiling and unplugging a PoE camera.
This is simply not true....passive poe is no more reliable or simple than a switch...it messy as well...the only thing they have going for them is that they are a bit cheaper...if you are going to lie and post this nonsense, then at least be honest and disclose that you work for a company that sells this crap. https://www.linkedin.com/in/tylerkandrews
 
Well Tyler you could have been a little more honest with your response. No harm telling people you are the CEO of a company that sells passive products. Try a different approach next time.
 
Can a passive POE device/switch be used to power Hikvision cameras? Like the devices from WiFi Texas and a few others. Something about passive vs af standard I don’t unite understand. Good and bad of passive. Thanks

About the only situation where I have used passive POE is when converting a non-POE camera (has only the DC power jack for power and a separate RJ-45 for network) to passive POE operation: Data on 2 pairs (1&2 and 3&6 ) and DC power on 2 pairs (4&5 positive, 7&8 negative) of the CAT-5e or 6. And as @fenderman pointed out, it can be messy in that (I assume) it's bulky and adds one more mechanical connection and just one more place to cause an intermittent connection.

About the only thing going for it, IMHO, is that it's relatively inexpensive and can get power to a cam that otherwise would need a nearby outlet for a wall wart power supply. Also, one must be careful about length of cable when adapting a 12 VDC camera to passive POE due to voltage drop.

Here's a typical passive POE splitter below, 1 piece for cam end and 1 piece for the end at switch, NVR, etc. This version has the 5.5mm outside x 2.1mm inside connector that fits most 12VDC cameras. Connectors for 5VDC cams are generally smaller (3.5mm outside x 1.35mm inside).

cam-mount-5_sm.jpg

And you'd have to have a way to hide that stuff and keep it out of the elements, like a box:

cam-mount-4_sm.jpg
 
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Also on passive PoE injectors all the over current protection is typically shared by all ports making it possible for a defective device to knock out all your devices.
 
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Well Tyler you could have been a little more honest with your response. No harm telling people you are the CEO of a company that sells passive products. Try a different approach next time.
I didn’t realize I was hiding the fact. My registration info is all from the company, and my picture matches my LinkedIn page. I believe in the value of the products we sell, and I’m happy to share the expertise we have whether it’s our products or someone else’s.
 
This is simply not true....passive poe is no more reliable or simple than a switch...it messy as well...the only thing they have going for them is that they are a bit cheaper...if you are going to lie and post this nonsense, then at least be honest and disclose that you work for a company that sells this crap. https://www.linkedin.com/in/tylerkandrews
Fenderman, if I wanted to hide the fact that I work for the company I wouldn’t have posted using my work email.
I do believe in what we offer. Passive injectors and switches have value and a place. 5 star ratings on Amazon and eBay show that we’re as serious about helping people as offering quality products.
 
Fenderman, if I wanted to hide the fact that I work for the company I wouldn’t have posted using my work email.
I do believe in what we offer. Passive injectors and switches have value and a place. 5 star ratings on Amazon and eBay show that we’re as serious about helping people as offering quality products.
Out of respect to others on the forum, I’ll make sure to disclose my affiliation as I contribute.
 
I didn’t realize I was hiding the fact.
Well you certainly didn't mention it.
My registration info is all from the company
Regular forum members don't see that - your profile does not show it.
and my picture matches my LinkedIn page.
Lol! Somehow I missed that.
if I wanted to hide the fact that I work for the company I wouldn’t have posted using my work email.
Regular forum members don't see what your email address is. Posting is via the forum, not via email.
The difference between passive and active PoE is the auto negotiation. Active devices do a handshake between the Power Supplying Equipment (PSE) and the Powered Device (PD) before it turns on the power. Passive is always on. It’s all about the right tool for the job.
The average user doesn't know or understand the technicalities, so that distinction isn't too relevant.
In my view, passive PoE is just a confusing cheat in the way product descriptions are worded that can catch unaware people out.
 
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There've been a few threads here where cameras have been damaged as a result of issues with passive PoE equipment and a few others where power quality or regulation issues were causing reliability problems for people. 99% sure some of these involved products from wifitexas/poetexas.
 
There've been a few threads here where cameras have been damaged as a result of issues with passive PoE equipment and a few others where power quality or regulation issues were causing reliability problems for people. 99% sure some of these involved products from wifitexas/poetexas.
Thanks for letting me know. I’ll look into those threads. We want to offer good that customers want.
 
Well you certainly didn't mention it.

Regular forum members don't see that - your profile does not show it.

Lol! Somehow I missed that.

Regular forum members don't see what your email address is. Posting is via the forum, not via email.

The average user doesn't know or understand the technicalities, so that distinction isn't too relevant.
In my view, passive PoE is just a confusing cheat in the way product descriptions are worded that can catch unaware people out.
Thanks for pointing out the distinctions. I’ll be more careful. Deception was not the intention.

We do both passive and active PoE because there is certainly a place for both. As you point out, with passive you do have to know what you’re powering and how. On the other hand it’s with the best intentions we tell people not to be oversold. I believe in picking the right tool for the right job. If an unmanaged active PoE switch fits the situation, I’m all for it.

The most important key is education on the technology to know how to pick the best tool.
 
802.3af/at based end devices expect the power sourcing equipment to provide certain protections the 'passive' 48V PoE just doesn't provide. Yes there are a few fuses or PTCs in there but it isn't enough imho.
 
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