Cat 5 ethernet cable question

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mdav056

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#220165 28-Jul-2017 18:14

I'm trying to increase the probability of getting this right first time...

I have a Cat5e run in my house that was put in by a sparky 3 years ago (not findable now), and because I am getting fibre, and the centre of my network may well change, I may have to cut and shorten this one cable and put a new plug on it.

My question is: what's the probability that he wired this up according to the A versus B configuration? Is one of these preferred in NZ?

gml

DarthKermit

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#1833044 28-Jul-2017 18:18

Can you find either end of the cable and determine if it's A or B?

mdav056

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#1833046 28-Jul-2017 18:20

I'm trying not to do that, as it means moving SO's overloaded desk to get to it!

gml

toejam316

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#1833047 28-Jul-2017 18:20

DarthKermit:

Can you find either end of the cable and determine if it's A or B?

Easiest solution, for sure, is to look at the end you're going to cut off and find the pin out, then duplicate it.

I've seen installations where they've made their own standard, instead of A or B. It's not common, but it's not surprising.

geocom

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#1833052 28-Jul-2017 18:51

Do you have a network tester? It would be the easiest way just try A first if it is wrong then try b

Otherwise you could crimp an LED into pins 1&2 of an RJ45 plug put a battery on the other end if the led glows when the battery is on White Green, Green then it is A if it glows when on White Orange, Orange then it is B. Remember an LED is a diode so the battery needs to be the correct way around also try it first with a coin cell battery if that does not work then up it to 2 new AA's. Although the extra current could kill the LED you could be safe and put a resistor on the led. Although this would be the same as getting a network tester.

Geoff E

mdav056

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#1833058 28-Jul-2017 18:59

Thanks, @geocom. Yes, I have a network tester, but wasn't sure that it would show a problem if it was A one end and B the other. I may have to suck it and see, then. Be fine so long as it isn't D E F or G, etc, as mentioned by @toejam316. If neither A nor B work, I'll move the bloody desk, I suppose...

Thanks, all

gml

loceff13

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#1833067 28-Jul-2017 19:38

mdav056:

Thanks, @geocom. Yes, I have a network tester, but wasn't sure that it would show a problem if it was A one end and B the other. I may have to suck it and see, then. Be fine so long as it isn't D E F or G, etc, as mentioned by @toejam316. If neither A nor B work, I'll move the bloody desk, I suppose...

Thanks, all

Assuming you mean network tester being one of these it would be simple to tell if it's not wired A-A etc as they won't line up..

mdav056

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#1833069 28-Jul-2017 19:43

loceff13:

mdav056:

Thanks, @geocom. Yes, I have a network tester, but wasn't sure that it would show a problem if it was A one end and B the other. I may have to suck it and see, then. Be fine so long as it isn't D E F or G, etc, as mentioned by @toejam316. If neither A nor B work, I'll move the bloody desk, I suppose...

Thanks, all

Assuming you mean network tester being one of these it would be simple to tell if it's not wired A-A etc as they won't line up..

Yup, similar. Thanks.

gml