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redsleeve

Power over ethernet questions

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So I am trying to power 2 cameras with poe. DS-2cd2232 and ds-2cd2532. Question is do I really need 802.3af switch (48v power) or will something else do?

 

Currently I'm looking into: http://www.planet.com.tw/en/product/product.php?id=1822#spec (4 port 802.3af poe)

http://www.tp-link.com/en/products/details/?model=TL-SF1008P#spec (also 4 port 802.3af poe)

and http://routerboard.com/RB750UP (4 port NOT 802.3af)

I would like routerboard because of usb port, but if 802.3af is a must, I can live without it

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You have several things going on here that I just don't understand at all.

 

The first one is you are comparing switches to routers which serve totally different purposes. Why do you need a router, don't you already have one on your network? Not a good idea to plug a router into a router.

 

Next, why would you think 8-30VDC will power a camera that requires 48VDC or are they selling you a model that has 48VDC, so I'm missing something here. What is the purpose of the Routerboard, it can't be for cameras is it?

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You have several things going on here that I just don't understand at all.

 

The first one is you are comparing switches to routers which serve totally different purposes. Why do you need a router, don't you already have one on your network? Not a good idea to plug a router into a router.

 

Next, why would you think 8-30VDC will power a camera that requires 48VDC or are they selling you a model that has 48VDC, so I'm missing something here. What is the purpose of the Routerboard, it can't be for cameras is it?

 

I am aware of switch versus router, also there is routerboard switch with poe (but not 802.3af also ). The reason I am favouring rb750up is as I mentioned usb port. I can plug 3g usb stick in it and get 3G access to ip cameras at location. It is gonna be remote location and there is no "ground" internet access yet, so 3G is one of internet options. Other is 5ghz wifi link (5 mile distance from me to this "offline" remote location).

Additionally, you can always use router as switch, but cannot use switch as router

 

8-30V is confusing to me too. They sell routerboard with 24V 2.5A power adapter, and claim it outputs 0.5A on each port max, so that would translate to 12W @ 24V. But on the other hand, according to 802.3af, max power should be 350mA @ 48V aka 15.4W per port. Two switches I mentioned use 48V 1.25A power adapter IIRC. I thought it only needed to output at least 10W on port and it could magically power anything But if 48V is a must as standard says for PoE cameras, then its clear as a day I can forget about powering anything with this routerboard. What can it power then? Other routerboards and stuff that is not 802.3af compatible??

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You have several things going on here that I just don't understand at all.

 

The first one is you are comparing switches to routers which serve totally different purposes. Why do you need a router, don't you already have one on your network? Not a good idea to plug a router into a router.

 

Next, why would you think 8-30VDC will power a camera that requires 48VDC or are they selling you a model that has 48VDC, so I'm missing something here. What is the purpose of the Routerboard, it can't be for cameras is it?

 

I am aware of switch versus router, also there is routerboard switch with poe (but not 802.3af also ). The reason I am favouring rb750up is as I mentioned usb port. I can plug 3g usb stick in it and get 3G access to ip cameras at location. It is gonna be remote location and there is no "ground" internet access yet, so 3G is one of internet options. Other is 5ghz wifi link (5 mile distance from me to this "offline" remote location).

Additionally, you can always use router as switch, but cannot use switch as router

 

8-30V is confusing to me too. They sell routerboard with 24V 2.5A power adapter, and claim it outputs 0.5A on each port max, so that would translate to 12W @ 24V. But on the other hand, according to 802.3af, max power should be 350mA @ 48V aka 15.4W per port. Two switches I mentioned use 48V 1.25A power adapter IIRC. I thought it only needed to output at least 10W on port and it could magically power anything But if 48V is a must as standard says for PoE cameras, then its clear as a day I can forget about powering anything with this routerboard. What can it power then? Other routerboards and stuff that is not 802.3af compatible??

 

2 cameras dont need much but ive got a feeling youre right and that routerboard can't power very much. It would be intesting to know. I would email routerboard directly and ask the question.

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There are 2 ways to run over a network cable without a POE switch:

 

- Use passive POE injectors and a 12Vdc PS. These put any voltage into the cable and pull it out the other end, where you'd plug the camera's 12Vdc power connector in. You'll have more power loss over long runs due to the higher current at 12Vdc vs 48Vdc.

 

- Use 803.2af POE injectors. These plug into the wall at one end and send 803.2af POE power through the cable to the other end.

 

Single unit - $18 - need one for each cam:

http://www.amazon.com/TP-LINK-TL-PoE150S-Gigabit-Injector-compliant/dp/B001PS9E5I/ref=sr_1_1?ie=UTF8&qid=1397765557&sr=8-1

 

Here's an 8 unit passive adapter that comes with a 48V 60W PS and provides power directly to the device:

http://www.amazon.com/WS-POE-8-48v60w-passive-Ethernet-Injector-cameras/dp/B0086SQDMM/ref=sr_1_2?ie=UTF8&qid=1397765820&sr=8-2

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Routerboard typically uses 24 volt injection for their non-standard version of POE. Their hardware is excellent, but the POE weirdness never made any sense to me.

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What I don't understand is what is the purpose of the PoE on that router? Do they sell phone systems or something that use those odd voltages? The only odd duck that I heard of before is Ubiquiti that uses 24V in their PoE products.

 

So I agree then, get router for 3G from them but get a model without PoE as you don't want to damage the cameras. We use a Cradlepoint router, mbr1200 that has USB 3g/4g capability at remote locations and use a Verizon Wireless USB stick. Then use PoE injectors or a PoE switch if you have more than 1 or 2 cameras attached to the router and that will work. We use a PoE injector because the location where I use this just has one camera.

 

If you are in the U.S., careful with 4G as there may be extra fees to connect remotely where 3G doesn't have those limitations. For example, VZW charges a one time $500 to allow this. Not sure what other carriers charge.

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Mikrotik has similar products as Ubiquiti (wireless bridging gear and routers/switches). A number of those wireless equipment manufacturers started making their products well before any PoE standards were in place. The passive low voltage injection for that equipment allows for lower cost products, as well as easier usage with battery powered equipment.

 

They are only worried about inter-compatibility between their products, and do not intend them to be used with 802.3af standard cameras or other equipment. Some people have used the larger Ubuiquiti switches that provide an option for a 48 volt output to power cameras, but they are not intended for that purpose.

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What I don't understand is what is the purpose of the PoE on that router?

 

To power Routerboard's wireless APs. They have a whole line of wireless gear like UBNT that is extremely powerful (feature wise) but not for a beginner user.

 

-KNo1B7K-YY

 

Routerboard/Mikrotik has some very powerful low cost routers which are very popular with WISPs.

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Michael, How do you like those compared to the Nano's?

 

If you are talking about Mikrotik SXT vs Ubnt nano, I have been told SXT is ok up to 5km because it has strange beam pattern?!

So I have always been looking at ubnt nanobridge. Now there is new equipment - nanobeam. If I ever do wifi link, its gonna be with nanobeam m5 300

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Michael, How do you like those compared to the Nano's?

 

If you are talking about Mikrotik SXT vs Ubnt nano, I have been told SXT is ok up to 5km because it has strange beam pattern?!

So I have always been looking at ubnt nanobridge. Now there is new equipment - nanobeam. If I ever do wifi link, its gonna be with nanobeam m5 300

 

Nanobeam M5 300 will be total overkill unless your doing a long range PTP link. NBE-M5-16, NBE-M5-19 will be used the most.

 

The longest link we worked on was 37miles using rockets and RD-5G-34 dishes

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I work with the M5 Nano almost daily.

Mostly shots of 300 meters or less. They have been pretty reliable. Occasionally one will mysteriously default itself. A firmware upgrade will remedy the problem.

I wish they were IP66 rated though. I'm not crazy about the little trap door out in the elements.

 

The biggest load I have put on a link was 2 Avigilon 5mp H264 cameras and 2 Avigilon 2mp H264 cameras.

That was pushing it and I had to cut the frame rate back a good bit to not pixelate.

I have also put an Axis Q6042 PTZ on one pole with a Nano station, shoot it to another pole with another Q6042, a pair of Nano stations, and a switch. And shot that back to a building. Works great and has been 100% up for a year and a half.

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The Mikrotik radios have a lot more options for advanced networking/routing internally, but they are much less user friendly for a basic user to configure. I used quite a few of them in the past, and got pretty familiar with them. I still use some in specialty applications, but have changed to Ubiquiti for almost everything else.

 

I purchase Nanostations by the case now, and have been very happy with them. Using shielded cable with them is an important detail, though.

 

Depending on the configuration and distance, you can get near wire-speed throughput from them. Testing using JPERF with a pair of Nanostation M5's yielded multi-threaded TCP stream throughput of 90+Mbps with 40MHz wide channels, 75+ on 30MHz channels, and 35+ on 20MHz wide channels.

 

There are some mounts/shields from a company called RF Armor which help quite a bit for better mounting, and interference shielding, especially if you are using multiple radios near each other.

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Michael, How do you like those compared to the Nano's?

 

If you are talking about Mikrotik SXT vs Ubnt nano, I have been told SXT is ok up to 5km because it has strange beam pattern?!

So I have always been looking at ubnt nanobridge. Now there is new equipment - nanobeam. If I ever do wifi link, its gonna be with nanobeam m5 300

 

Nanobeam M5 300 will be total overkill unless your doing a long range PTP link. NBE-M5-16, NBE-M5-19 will be used the most.

 

The longest link we worked on was 37miles using rockets and RD-5G-34 dishes

 

Nanobeam m5-300 is only 22db AFAIK. My PTP link will be 9km/5.5mile. Only sad thing is that nanobeam m5-300 has 10/100 ethernet, and only m5-400 has gigabit. I have read on ubiquiti forums people using nanobeams and nanobridges for links under 500metres Now that is overkill because they had to lower output to get to -55 signal )

Price here is almost the same for nanostation loco m5 and nanobeam, so thats why I am looking at nanobeam in the first place.

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I work with the M5 Nano almost daily.

Mostly shots of 300 meters or less. They have been pretty reliable. Occasionally one will mysteriously default itself. A firmware upgrade will remedy the problem.

I wish they were IP66 rated though. I'm not crazy about the little trap door out in the elements.

 

The biggest load I have put on a link was 2 Avigilon 5mp H264 cameras and 2 Avigilon 2mp H264 cameras.

That was pushing it and I had to cut the frame rate back a good bit to not pixelate.

I have also put an Axis Q6042 PTZ on one pole with a Nano station, shoot it to another pole with another Q6042, a pair of Nano stations, and a switch. And shot that back to a building. Works great and has been 100% up for a year and a half.

 

most cameras we have on one PTMP link is 6 Avigilon 5MP bullets at 7FPS. Rocket M5 with 2 NanoBridge M and Toughswitches

 

As everyone else stated shielded cable is a must and RF Armor is very helpful

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