5VDC 120mA to USB for multisensor over PoE?

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Disrespective

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#196807 13-Jun-2016 15:07

I have a few home automation sensors which can run on batteries, or permanently powered by 5VDC though USB. I also have a switch which supports PoE af and at, and a few spare ports.

Rather than go and run 240V to each sensor, and then wire that up to some USB power keystones (which I have a bunch of anyway fwiw) I wondered if I could just use up my cat6 roll by running it to each sensor location and use PoE to power them permanently.

Has anyone come across a method to use PoE to get 5VDC at the end of a max. 40m cat6 ethernet run and then terminate it with a female USB? Might this be easier to make something myself?

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#1571079 13-Jun-2016 15:12

I have used a couple of these along with one of these. Not the cheapest option by far, but they work very nicely out-of-the-box. And I don't have a POE switch so these suited me. I am pushing 12VDC down the wires and I guess the longest run is probably close to 30m (hard to tell exactly as the CAT6 is in the walls). Never had any issues. I think you are better off sending higher voltage (i.e. > 5VDC) down the wire and down converting at the sensor since the high voltage allows for longer distances in case there are losses. I am not a V expert however..

pbgben

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#1571084 13-Jun-2016 15:21

You could try running passive POE, be careful not to plug it into things that aren't passive supporting(Magic smoke)

Or, you can get a POE compliant splitter and then use a buck converter to get the 5v. (<$10 on AliExpress)

$5USD 1GB RAM, 10GB SSD VPS in SYD

geocom

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#1571089 13-Jun-2016 15:29

You could use something like this http://www.tp-link.com/en/products/details/cat-4794_TL-POE10R.html with a female USB to barrel plug or just solder one together.

You could use Passive POE however it would require a higher voltage to be applied and if it has no voltage regulation on board it could be bad.

Geoff E

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#1571107 13-Jun-2016 16:08

There are PoE regulators sold on aliexpress etc made to drop into an arduino shield etc, I dont know what would happen if you just hooked one up to one pair into each terminal, in theory it should still negotiate and present the correct load resistance to the switch to have it turn on, but I know that one of my switches gets upset and drops the power if there is no link established some time after the power turns on.

Richard rich.ms

sbiddle

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#1571110 13-Jun-2016 16:12

geocom:

You could use something like this http://www.tp-link.com/en/products/details/cat-4794_TL-POE10R.html with a female USB to barrel plug or just solder one together.

You could use Passive POE however it would require a higher voltage to be applied and if it has no voltage regulation on board it could be bad.

I would use a PoE to 5V adapter like the one above. There are a few companies that do similar adapters. I've never seen a premade 2.5mm to USB cable though - but I'm sure the OP has got the skills to make one if they're tinkering with this stuff.

chimera

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#1571130 13-Jun-2016 16:18

Search Amazon for WT-AF-5v10w

Dell

Shop now for Dell laptops and other devices (affiliate link).

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#1571149 13-Jun-2016 16:42

sbiddle:

geocom:

You could use something like this http://www.tp-link.com/en/products/details/cat-4794_TL-POE10R.html with a female USB to barrel plug or just solder one together.

You could use Passive POE however it would require a higher voltage to be applied and if it has no voltage regulation on board it could be bad.

I would use a PoE to 5V adapter like the one above. There are a few companies that do similar adapters. I've never seen a premade 2.5mm to USB cable though - but I'm sure the OP has got the skills to make one if they're tinkering with this stuff.

These are pretty common but output 12v.

http://www.aliexpress.com/item/48V-input-38-38mm-ip-camera-poe-module-ip-camera-module-board/32650013083.html

Made to go inside an IP cam to add POE, you could then drop a 12v to 5v converter board on that, which are all over aliexpress for about a dollar.

I bought some of these to go into the raspberry pi to take a cable from a tplink POE adapter that outputted 5v. Works fine. Ecxept the round part fouls one of the cases I have.

http://www.aliexpress.com/item/10pcs-DC-5-5mm-x-2-1mm-5-5-2-1mm-DC-Female-to-Micro-USB/32558585832.html

Richard rich.ms

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#1571151 13-Jun-2016 16:43

chimera:

Search Amazon for WT-AF-5v10w

Thanks. The USB version of this looks like it's pretty much exactly what I want, and not going to add a HUGE amount to an already growing cost...

chimera

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#1571159 13-Jun-2016 16:58

Disrespective:

chimera:

Search Amazon for WT-AF-5v10w

Thanks. The USB version of this looks like it's pretty much exactly what I want, and not going to add a HUGE amount to an already growing cost...

Yep, specifically this

Its a small price to pay for simplicity really.

If you're in Auckland, order an extra one and I'll come grab it off you and flick you some cash

pbgben

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#1571165 13-Jun-2016 17:07

chimera:

Disrespective:

chimera:

Search Amazon for WT-AF-5v10w

Thanks. The USB version of this looks like it's pretty much exactly what I want, and not going to add a HUGE amount to an already growing cost...

Yep, specifically this

Its a small price to pay for simplicity really.

If you're in Auckland, order an extra one and I'll come grab it off you and flick you some cash

Here's the direct from china link.

$5USD 1GB RAM, 10GB SSD VPS in SYD

chimera

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#1571173 13-Jun-2016 17:25

pbgben:

chimera:

Disrespective:

chimera:

Search Amazon for WT-AF-5v10w

Thanks. The USB version of this looks like it's pretty much exactly what I want, and not going to add a HUGE amount to an already growing cost...

Yep, specifically this

Its a small price to pay for simplicity really.

If you're in Auckland, order an extra one and I'll come grab it off you and flick you some cash

Here's the direct from china link.