Cat 5 wiring (2025 Update)

Understood. I'm actually doing several things with the cat 5. One of them is a whole house audio system which uses their female wall jacks, necessitating me to crimp on connectors to plug into their wall jacks. Also, this cable is running through plastic conduit, which will not allow me to use premade cables due to the size of the connector. I am also doing wall jacks thru the house, which do use punch down jacks. I realize my main snafu was stripping the conductors, instead I now leave the insulation and crimp through it. Many thanks to all that contributed.......

That is why I asked if 2 pair cat 5 cable exists?

Can you use 2 pair cable for 100Mhz ethernet?

snipped-for-privacy@dog.com wrote: ...

For what possible reason such a blanket statement?

No.

There goes the theroy that there are no stupid questions!

Sure, you can get 2 pair or 50 pair. Two pair is not commonly used because the install would save a couple pennies and it isn't standard practice. And you would be shooting yourself in the foot if you wanted to say use GigE which uses 4 pairs.

and the other wires (in the 4-pair cable) help hold the pairs you need in place, so it isn't so hard to get the connectors on right.

But that is of little use in standard practice since both ends are punched down, one end on the patch panel and the other on the jack.

It is called overkill. The phone company has been using 2 pair for......well a long time. :)

The telephone guy shushed me for suggesting he use the other pair to add another phone line in an office. They don't even use the extra wires to fix a broken one. It pays better not to ask such questions.

In fact, it would be a mistake to strip them.

how about answering the question, whether or not you think it's stupid?

BTW, my understanding is that plenum cable doesn't ignite as easily, but has worse fumes once it does ignite, so it's not a trivial issue.

Here's some info:

The Daring Dufas wrote: ...

None of which has any bearing on the question of just what it is about CAT-5 cable that is so prone to needing a plenum fire rating for a residence where nothing else is going to be, anyway. I presume the high data rate is likely to generate sufficient friction within the conductors as to cause salty to be worried self-ignition?

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:) spew coffee

I install a lot of the stuff. The city here requires that it be used in commercial buildings whenever the drop ceiling is used as a return air (plenum). I see no reason to use it in a home unless you're using the HVAC ductwork as a wiring chase. Plenum cable is a lot more expensive than non-plenum. For some strange reason Domino's Pizza Corporation specifies Cat5 plenum for the installation of their new Pulse POS systems. I have yet to see a Domino's that used the ceiling as a return air. I think Salty Canine is just plain grouchy, I'm like that sometimes and the older I get, the less tolerant of aberrant behavior I am. DAMN KIDS! GET OFF MY LAWN!

TDD

The Daring Dufas wrote: ...

Those both make sense are are Code or local variation/requirements.

The question remains about the point raised earlier that makes no sense at all.

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In a fire, non-plenum rated wiring gives off very toxic fumes. Very toxic. The reason it is especially important in a plenum is that any air handling systems will blow those fumes into other areas that may be occupied, eventhough uninvolved in the actual fire. In a house, it is far more likely that smoke will be in all areas in a very short time, even without assistance from the air handling system.

Poison gases may dramatically reduce your chances for getting everyone out alive.

Are you referring to blanket statements? If an ignorant person wants to use very expensive plenum cable when he/she/it doesn't have to, send them to me. I'll sell them all they can afford. Someone like that reminds me of a fool who will shell out unnecessary money to buy premium gasoline for his/her/its minivan.

TDD

Where was a plenum any portion of the thread and mentioned in the recommendation I questioned as part of the suggestion to use it no matter what? That's what I was after was why the blanket suggestion.

If you mean to restrict the recommendation to locations where it make sense, that makes sense (doh!). Otherwise, it simply is a waste of money as there's little if any benefit going to be gained in a fire any way given the relative amounts of material in other contents that are also toxic.