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  Reply # 190704 20-Jan-2009 08:58
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Criggie:
nate: ...we sourced some PoE adapters (such as this) from China. Basically plug in Ethernet on one side, and it has a jack on the other, and a small power adapter.

Be careful as I'm sure the limit of data (before it starts to degrade) over Cat5 is 100m.




Those are injectors - some obey POE standards, some don't. The problem is a cablemodem is 240V not 12V.


The cable modems are 12V DC ~1A and run off a plug pack.

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  Reply # 190734 20-Jan-2009 10:23
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Structured cabling standards AS/NZ3080 require 100m total length as Richard stated, and is worked around a 90m solid, 2x 5m stranded patch cord setup, however this is a standard that specifies a safe working headroom but must be adhered to for AS/NZ3080 compliance, this need not apply in your situation. The cicuit length is limited by the point where the NIC reciever starts to error which from my experience is way north of 200m, Richard says he's tested 300m and it works, and I am not surprised. In a tempory setup some yrs ago I ran several 140-170m concatenated runs with switchs between, from my testing there was no packet loss end to end, and over around 8hops still returned ping times <1mS, so there is a lot more headroom there if you are prepared to take the risk, although for commercial applications where complicance certificates are needed 100m is still required as once you step significantly over 100m you step into nomans land.

As Steve says the Motorola surfboard modems run on 12V with a max draw of 1A, and its my guess based on most of these products that the 12V immediately meets a 3.3V and 5V switching regulators which will probably be fine running with an input supply between 20V or more and down to around 8V input, so a long lossy POE cable run probably wont be a big issue, otherwise run 24V supply at the headend with a 12V switch mode regulator at the modem.

Cyril

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  Reply # 190740 20-Jan-2009 10:44
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cyril7: ...a long lossy POE cable run probably wont be a big issue, otherwise run 24V supply at the headend with a 12V switch mode regulator at the modem.

I have done this kind of thing with a 48VDC supply at the Head End and an Innovative Energies 48VDC to 12VDC converter at the Modem End.

It reduced the current through the Ethernet cable from 1 Amp peak down to 300mA or so and by parallelling up the unused pairs in the Ethernet cable, it kept the losses down too.  This system has been running over 100 metres of cable for over 5 years now with no problems except for a couple of lightning strikes.

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  Reply # 190753 20-Jan-2009 11:52
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Thats what those POE kits do, a 48v PSU goes in at one end and the other end has a regulator to either 5 or 12v depending on which you buy.

They are all midspan however so you need all 4 pairs present in the cable. I have yet to see any endspan compatible power injectors or takeoffs - but untill I need to run gigabit to a phone or wireless accesspoint then the spare pairs are spare so will do just fine.




Richard rich.ms



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  Reply # 190771 20-Jan-2009 12:56
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sbiddle:
Criggie: The problem is a cablemodem is 240V not 12V.


The cable modems are 12V DC ~1A and run off a plug pack.


ARGH! sorry! I was thinking of the old GE surfboard ones which do have 240V. The newer black motorola have a plug pack and POE should work wonderfully.

Now all I have to do is convince TCL to terminate their shizzle as far up the drive as possible, and find a suitably sized waterproof box, then run cat5 from the house.

Thanks heaps everyone.

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  Reply # 190773 20-Jan-2009 13:06
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Cabnetisation in Hoon Hay began late 2008 and is scheduled for completion and to be turned on July 2009
I lived in Hoon Hay up until the end of 2008. The speed setting you advise arepretty identical to mine. They should be fixed up quite a bit once the cabinets go live.
You can check on when the cabinets are scheduled for completion here

http://www.telecom.co.nz/broadband/speed/adsl2

I think those documents over on the chorus website are a little bit out of date (innaccurate)



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  Reply # 190967 21-Jan-2009 08:17
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farcus: Cabnetisation in Hoon Hay began late 2008 and is scheduled for completion and to be turned on July 2009
I lived in Hoon Hay up until the end of 2008. The speed setting you advise arepretty identical to mine. They should be fixed up quite a bit once the cabinets go live.
You can check on when the cabinets are scheduled for completion here

http://www.telecom.co.nz/broadband/speed/adsl2

I think those documents over on the chorus website are a little bit out of date (innaccurate)


According to the website you gave, its already adsl2 capable.

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  Reply # 191052 21-Jan-2009 14:03
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Iguess it depends where you live in Hoon Hay then.
I lived on Hoon hay Rd toward Maryhill ave and got a connection of around 5 mb
Due to be connected to a cabinet July 2009

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