sirus
Posts: 27
Joined: Thu Jul 14, 2016 1:07 pm

Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 1:10 pm

Hi guys,

I looking buy some Active PoEs to power up my Pi and HDD. My HDD requires 2 Usb connections via a USB-Y cable to work and current the pi doesnt have enough power to get the disc spinning, despite setting max_current_usb=1.

I am probably going to use one PoE to power the Pi and another to power 1 of the HDD usbs whilst having the other connected to the pi.

Just curious really if anyone has played with PoEs or messed around shareing power sources for a HDD?

fruitoftheloom
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 1:41 pm

sirus wrote:Hi guys,

I looking buy some Active PoEs to power up my Pi and HDD. My HDD requires 2 Usb connections via a USB-Y cable to work and current the pi doesnt have enough power to get the disc spinning, despite setting max_current_usb=1.

I am probably going to use one PoE to power the Pi and another to power 1 of the HDD usbs whilst having the other connected to the pi.

Just curious really if anyone has played with PoEs or messed around shareing power sources for a HDD?
As you have a RPi 2B do you have a good quality 5V2A PSU or better ??

http://uk.rs-online.com/web/p/plug-in-p ... ly/9098135

http://uk.rs-online.com/web/p/plug-in-p ... ly/9098126


Though if you want to spend £30++ on 2 x PoE Kits see:

viewtopic.php?f=46&t=154158


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sirus
Posts: 27
Joined: Thu Jul 14, 2016 1:07 pm

Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 1:51 pm

Yep my PI2 has the official 5V2A adapter. Still the disc is not spinning unless I am missing some config.

This is one of the PoEs im thinking of getting:

https://www.amazon.co.uk/DSLRKIT-Active ... Active+POE

6by9
Raspberry Pi Engineer & Forum Moderator
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 1:57 pm

https://www.amazon.co.uk/Raspberry-micr ... 0108TD78Y/ certainly work with just a Pi3.
I don't know how much extra stuff it will handle though, and I think an earlier version didn't have the extra blob on the power cable ending in the uUSB plug.

Switch to an SSD mounted in a USB housing instead of a HDD? It'd have lower power requirements and be quieter.
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fruitoftheloom
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 2:09 pm

sirus wrote:Yep my PI2 has the official 5V2A adapter. Still the disc is not spinning unless I am missing some config.

This is one of the PoEs im thinking of getting:

https://www.amazon.co.uk/DSLRKIT-Active ... Active+POE
You will need an Injector / PSU as well !


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sirus
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 2:21 pm

Wouldn't powering it through the modem be enough?

6by9
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 2:32 pm

In both cases they support IEEE 802.3af, so support in the switch means no extra cabling or accessories needed at the switch end.
(I'm assuming that is what sirus means by the modem).

We have several of the RocksolIT adapters running Pi's off a Netgear PoE switch with no extra hardware.
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fruitoftheloom
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 3:04 pm

6by9 wrote:In both cases they support IEEE 802.3af, so support in the switch means no extra cabling or accessories needed at the switch end.
(I'm assuming that is what sirus means by the modem).

We have several of the RocksolIT adapters running Pi's off a Netgear PoE switch with no extra hardware.
Yes the Netgear or similar PoE Switch acts an injector.........

http://www.internetvoipphone.co.uk/chea ... witch.html


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sirus
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 4:05 pm

So would a TalkTalk modem/router be sufficent enough to act as an injector?

I've attached a pic explaining what I'm hoping to achieve without the hdd.
Attachments
pi.png
pi.png (9.82 KiB) Viewed 1314 times

fruitoftheloom
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 4:11 pm

Why would you think that would work, despite what previously posted ????


https://en.wikipedia.org/wiki/Power_over_Ethernet
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fruitoftheloom
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 4:30 pm

The cost of PoE is as expensive as a USB3 USB HDD

http://www.argos.co.uk/static/Product/p ... 614447.htm


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drgeoff
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Re: Using Active PoEs to power pi and hdd

Thu Jul 28, 2016 5:43 pm

I've see quite a few home modem/routers (possibly more than 99% of forum members have seen) and none of them had PoE supply/injector capability. A Talktalk one will not be an exception.

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