strange cat5 wire connection

[frank10]

I know I can connect an ipcam with only 4 cat5 wires, but now I found a cable just used for other purposes and it has 4 wires used (with CC current) BUT not same couples, so I left with 1 couples and 2 wires from different couples free.
Furthermore I should solder them with a new cat5 to lenghten it.

So my questions are: can it be loss of some data
1) using wires not from the same 2 couples?
2) soldering them at both end of the cat5 cable?

 

[MnemonicMonkey]

From what I understand, no. You need 2 pairs. They must be twisted together to avoid noise and data loss.

Sent by my Trunk Monkey™

 

[bguy]

I'm not 100% clear on everything you asked. I don't know what you mean by "CC Current", or "not same couple".

10 and 100 Mbit network cable needs 4 wires, or more accurately, 2 twisted pairs. Cat5 (and Cat5e) has 4 pairs (8 wires). But you only need 2 pairs for 10 and 100 Mbit. The twisted pairs reduce interference, and are used in pairs. If you wire them up mixing the pairs, you will probably have problems.

It sounds like you have some non-network cable that has 4 wires, and you want to use it as network cable. It might work, but it most likely will not work well, if at all.

Use Network cable for networking.
Don't solder the cable to make it longer.
Don't share the cable with other uses.
Wire it up correctly.

 

[frank10]

Use Network cable for networking.
Don't solder the cable to make it longer.
Don't share the cable with other uses.
Wire it up correctly.

hehe, obviously, if I could the problem is I have to use that existing cable (that IS anyway a cat5e cable) because there is no room to place another one...
Let's say I have green and white green couple plus blue and orange wires used with 12V and other low voltage current.
It remains only the
white orange
white blue
brown
white brown
to use @100Mb (for ipcam bandwidth)
So the first problem is I have to deal with white orange and white blue: they aren't the same couple...
The second problem is soldering... yes, if I shouldn't do it I would, but the cable is too short: I must do it at both ends...

Anyway using it only @100Mb and also with a low transfer rate such as <8Mb/s I think it could work. I hope...
Also, there should be not interference as in the other wires there is direct current, not data transfer.

btw:
I wrongly wrote CC (in my language) meaning DC in english...

 

[t84a]

You have to use the colors together. Blue with blue/white, orange with orange/white, green with green/white, and brown with brown/white. You want to use pins 1&2 and 3&6 of the 8 position RJ45. To extend the cable, terminate the end with a RJ45 (male) and buy or make and extension cable with male RJ45s on each end and simply use a CAT5 coupler. This is the best you can do.

 

[bguy]

100 Mbit signal is going to be pickier in wire quality that 10 Mbit. Just keeping a link with a poor cable will be harder on a 100 Mbit link. The length of the run will also matter if you do non-standard things.

You should only use twisted pairs for the network. If you use random wires, you will have problems, even without trying to run power on parallel wires. If all you have left is orange/white, blue/white and the brown pair for the network, you won't have a reliable link. Generally you would use the green and orange pairs, but you can get away with different pairs, as long as they are pairs.

You can probably get away with running DC over the unused wires. But in general it should be avoided. Give it a try and see if it works. But if you don't have 2 twisted pairs for the network, I wouldn't get your hopes up.

 

[frank10]

Ok, thank you all.

To extend the cable, terminate the end with a RJ45 (male) and buy or make and extension cable with male RJ45s on each end and simply use a CAT5 coupler.

Yes, that is another possibility, but I think the soldering should be better, having a more solid contact and also 1 only vs the 2 contacts with the coupler. It should be more db S/N I think.

 

[Kawboy12R]

Run the proper cable. Just do it. Don't solder because you think you can save a few cents over connectors and wire that will actually work.

 

[frank10]

Cents don't matter at all: I talked about db.

 

[t84a]

Good luck.

 

[Kawboy12R]

And I was talking about industry standards that are used so that Ethernet actually works. Loss at a connection point isn't nearly as important as noise and crosstalk rejection, both of which aren't of concern to an electrician with a soldering gun joining untwisted wires that aren't designed for carrying data. The dB loss at a proper connection is insignificant, whereas what you're trying to do and use is at best a roll of the dice dependant on things that people on the other side of your screen have no knowledge or control over, like how close your existing non-network wire runs to AC power wires or noisy motors or fluorescent light ballasts. This is in addition to the crosstalk between your existing wires themselves.

Solder them if you want, but if the network doesn't work reliably with them even jellybeaned together then I doubt soldering will help. Solder away, but nobody "here" can tell if your existing wires will work "there" without actually trying it. Any advice to the contrary besides following proper network practices is guesswork.

I'm not trying to insult you. It's just the truth. You need 2 properly twisted pairs of wire to reliably carry data even when they're routed away from possible major electrical noise sources. Unknown wire routed who knows where with who knows what kind of insulation around non-standard connections whether soldered or not? Who knows? My recommendation for solder would be to insulate the joints well and continue the twists in the wire as long as possible. Industry standard connections already account for that though.

 

[bguy]

Ditto what Kawboy12R and t84a said. Ethernet is picky in the best of cases. I have a Fluke meter that certifies Ethernet, and a 90 meter run just barely passes with everything done correctly with high quality cable. I've seen 10 meter cables that were wired "correctly" not work due to excessive attenuation from a bad termination. Likewise, I've seen cables that were wired as you describe with 1 pair, and 2 wires from different pairs, and they failed.

So give it a try, and good luck. But I doubt it'll work well.

 

[frank10]

Ok, thank you all.
I didn't mean to be nitpicky, it was just some thoughts to dig more.