DIY PoE

Jaa you can actually run 2 network lines in a network cable.
1,2,3, and 6 in the cable is used you can use the other wires for some thing else .
I have used the other pairs for Poe on IP cams instead of running other power cables.
BTW dont use one of those cable testers with the lights if you use the other pairs for some thing else the lights dont work because there is no return .
 
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sigh...

Please, PLEASE don't do this...

And no - your network will NEVER be able to operate at anything over 100mbps either...
 
HavocXphere said:
Care to elaborate why not?
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The moment you deviate from an standard, it becomes troublesome for someone else. Imagine you decide to run 1 100mbps and 2 analogue phone extensions through your CAT5 cable at the office. 3 years later, you leave...

Now a new guy comes in, replaces a switch / patch panel / whatever, and low and behold - 110V gets zapped through his Switch and/or NIC in the PC, and equipment is blown.... (and this can happen to someone at your home as well, as CAT5 is generally low voltage and doesn't carry enough to shock anyone - no one really cares to be careful with the connectors / exposed copper on the connectors.... Untill ofcourse, you deviate from an standard, and put high voltage on it).

Nevermind the actual hazzard of serious equipment failure, or electrical shock, there is also significant issues in terms of interference and EMI inside the cable which will have an impact on the performance of the network (this can affect other cables in the same 'bundle' as well if STP isn't used. Then there's ofcourse also the complete lack of future upgrading, and potential fire hazzards of wires melting due to heat due to the high voltage over the cables not designed to carry it. Lastly, it's ofcourse, absolute FUN to troubleshoot performance issues with crap like this as well...

It's plain and simple bad practise.

Spend the R25 and buy an propper passive POE injector if you require POE, or R125 odd (which includes an power supply), and do things 1) safely, and 2) correctly. Even better, 3) buy propper 802.3af enabled equipment with an 802.3af capable switch...
 
savage said:
The moment you deviate from an standard, it becomes troublesome for someone else.
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Sure - its not exactly standard compliant. But I think most people caught on to that fact after the mention of "DIY" and "electrical tape".

savage said:
110V gets zapped through his Switch and/or NIC in the PC [...] Untill ofcourse, you deviate from an standard, and put high voltage on it).
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Routers generally run off 12V...so I'm not quite sure where your 110V fits in, let alone "high voltage".:confused:

savage said:
heat due to the high voltage over the cables not designed to carry it
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afaik its the amperage producing the heat, not the voltage.

By my calculations it should be well within reasonable limits, but you're welcome to prove otherwise.
 
savage said:
It's plain and simple bad practise.
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I couldn't agree more, but that being said, nowhere does it say it's a good idea or according to any sort of good (never mind best) practice. Just that it is possible. I agree, this is by no means anything that should be done on any sort of production network.
 
savage said:
Now a new guy comes in, replaces a switch / patch panel / whatever, and low and behold - 110V gets zapped through his Switch and/or NIC in the PC, and equipment is blown.... (and this can happen to someone at your home as well, as CAT5 is generally low voltage and doesn't carry enough to shock anyone - no one really cares to be careful with the connectors / exposed copper on the connectors.... Untill ofcourse, you deviate from an standard, and put high voltage on it).
Click to expand...

Logic fail. This scenario will arise whether you use a standard PoE injector or a DIY version.

We've been using custom PoE devices where required for ages without any issues, albeit not as ghetto as described in OP's link.

If you are really concerned about future events, rather just label your cables correctly.
 
HavocXphere said:
Well kinda...not true PoE. Looks like a neat trick anyway.

Judging by the HN comments this might not be compatible with gigabit lans though.

http://tech2.in.com/how-to/wifi-routers/how-to-make-a-power-over-ethernet-poe-adapter/223062

NB I have not tested this - use at own risk.
Click to expand...

Why do this when you can just purchase these :

http://www.scoopdistribution.co.za/product_info.php?products_id=1270

http://www.scoopdistribution.co.za/product_info.php?products_id=755

Injector on one side and splitter at the remote device side, much simpler neater and safer!
 
HavocXphere said:
Well kinda...not true PoE. Looks like a neat trick anyway.

Judging by the HN comments this might not be compatible with gigabit lans though.

http://tech2.in.com/how-to/wifi-routers/how-to-make-a-power-over-ethernet-poe-adapter/223062

NB I have not tested this - use at own risk.
Click to expand...

I have done this so many times but please note that it works with 100Mbs ethernet only. When you have gig ports it uses the brown and blue pairs for data and power.

EDIT*** for home use ONLY!!!! Never in production environment. I swear if i find this in a client infrastructure. I will find you and kill you :D

30636971.jpg
 
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I see this in IP access control, IP CCTV and other related IP installs quite some times. I do not believe in these short routes, basically what savage said and I never improvise in business, rather plan everything appropriately. Rather get a PoE switch in the installation and run all the cables separately. DIY is all good though, should it be temporary.
 
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