Question Flat Cat8 Cable - - - do I need a specific RJ45 ?

[Orias]

Hey folks,

Quick question that I can't seem to find any clear answer to using Google.

My little home office room receives a pretty slow connection from the router, about 15-20% of the 1000mb/s connection that I have.

In order to try to remedy this, I bought a flat Cat8 cable, and threaded it through a few gaps/walls through to my office. In order to avoid having to cut out large holes, I cut off the RJ45 connector on one end, intending to fit a new one once the cable had been threaded. Before I did this, I tested the cable, and it was fine, I got the full 1000mb/s through it. The problem I have now, is that no matter what I try, I can't seem to get the thing to connect once I add a new RJ45 connector. There is a pretty high chance that I've messed it up, as the Cat8 wires are very small and fiddly. I have some passthrough connectors arriving soon, which should be easier to see and check that the wire order is correct. However, one thing I wanted to check is whether a standard RJ45 connector is suitable for Cat8? I can't see any difference, and the connectors/wire colours all look the same as Cat5/6/7 etc. It's just the wires that seem a bit more delicate, so I'm not sure if that needs a specific connector to ensure they "connect".

I hope that makes sense?
Cheers, Ori

 

[bill001g]

Yes you need a actual ethernet cable.

It is highly unlikely you purchased any "cat8" on amazon or ebay or where ever. They are extremely expensive cables used only in high end data centers. The are used when you need to go more than 40mbit.

Next any kind of flat cable does not meet requirements to be a ethernet cable. It just happens to be a wire that has rj45 ends that might sometimes work. In addition it also requires non standard rj45 ends that are almost impossible to buy.

You only need cat5e cable for 1gbit you would use cat6a if you needed faster. All this cable requires that the wires be pure copper (no cca) and have wire size 22-24. Flat cable has wires that as you found out are much much too small.

I have never actually found ends for that flat cable. I have found end that will take flat cable used in PBX phone systems but the wire size it accepts is still the standard 22-24. Even then it will be hard to trust who you buy the ends from because the cable you have were not built to any standard so it maybe incompatible with end from other vendor even if you would find some that take the correct wire size. This is partially why there is a standard for ethernet cable so all the cabling and equipment works together.

Unfortunately amazon allow this fake cable to be sold, they even sell it themselves. They crack down on counterfeit purses but allow so much other fake stuff on their site. It is too bad the industry groups that do cable certifications are groups of engineers rather than a company that would sue for counterfeit product being sold.

 

[Orias]

Thanks very much for that. I didn't think it was "real" CAT8, as when I was looking for connectors, it was just bringing up these very heavy-duty (and expensive) things!

I know the cable works (or worked) fine, as I tested it before I cut the end off, and I got the full speed I was expecting. So I figured "okay, no problem, cut one end off, feed the cable through the walls, and attach a new RJ45 to the end once that's done". Unfortunately, my efforts so far haven't worked. As I said, it's fiddly as hell, so there's every chance that the wires aren't ending up in the order that I want them. Hence why I have some pass-through RJ45 connectors arriving soon, so I can see where the wires are properly.

Here are a few pictures of the end that I cut off. From what I can see, it looks like most other cables I've used in the past. And there's a few videos online showing people attaching the RJ45 connector to similar looking cables, with similar small wires. So, with that in mind, I figured it should work easily enough... but no joy yet

 

[bill001g]

Your problem is printed on the cable. Unless you found some ends rated for 30awg wire it will not work. 30 awg wires is less than 1/2 the diameter of the standard cable. The small copper connectors inside the rj45 jack cut though the insulation to make contact with the wire inside.

They are designed very precisely and will not cut deeper than the diameter of 24 gauge wire to avoid cutting the copper wire itself but fully cut the insulation. In the case of most 30awg wire the diameter of the wire and the insulation together likely is still smaller than 24 gauge wire. So when you use standard ends on this thin wire they will not cut though the insulation and make contact with the copper wire.

Like I said I have never found the ends. You also need ones that will crimp flat cable. The ones that do round do not go tight enough to prevent the cable from being pulled out of the rj45 end if you accidentally tug on it a bit.

 

[Orias]

Ahh, ah heck, well that all makes a lot of sense! So it really all boils down to me getting this flat cable, to save making bigger holes in my apartment, rather than some standard, round AWG 24 CAT6 or 7 stuff.
It's not my apartment, so I wanted it to be easier to fix the little holes I make when I leave, but I could probably get some standard round cable through there with minimal extra damage now I guess.

Thanks again for the help, should have come here first, but I guess I would never have known

Cheers

 

[DSzymborski]

It's not like they're that big. Still super easy to spackle over.

 

[Orias]

Haha, true, although I've also punched some holes through some wooden doorframes, which are harder to hide!

One last question, I see some CAT7 stuff that says it's AWG 33, would that still work with CAT6 AWG 24 connectors, or would I need different ones for that (I have a bag of CAT6 RJ45 connectors, so easier if I can use those)?

 

[Orias]

Well, don't ask me how! But I got it working! The passthrough RJ45 connectors arrived, so I just figured I would give it a go with the 30AWG flat wire anyway. And after 1 failed attempt (wired it up back-to-front), the 2nd attempt seems to be working!
Did a quick speed test, and on WiFi I was getting 250-300mbps, I'm now getting 970mb/s (up and down). So I guess the connections did make contact when I crimped them! Pretty happy that I don't need to try to rewire everything around the house again now, so I'm not going to touch anything else, and I'll just call it "job done" for now 😀

 

[bill001g]

Just be careful to not move it around much it could disconnect unexpectedly.

The so called cat7 cable you list is also fake cable. Any cable with wire size less than awg 24 (ie a bigger number) automatically disqualified it for being a ethernet cable. Also even cat7 cables with valid wire are not worth buying. The cat7 standard was never fully finalized and provides no benefit over cat6a cable which is rated to 10gbit at 100 meters.

This all comes down to the silly consumer who thinks bigger numbers are always better when for home ethernet very few people need anything other than cat5e.