Faulty Ethernet cable?

[wheeshty]

Hi,

I’ve just got my new broadband router set up in a half finished new build (it’s dry at least) and I’m trying to run two Wi-Fi ‘extenders’, 1 to my office and 1 to my caravan. 

The office set up is running fine - a 40m run of  cat5e cable from the Ethernet port in the router to the wan port on my old 4g router so the office has Wi-Fi. 

The problem is the caravan - I fitted RJ45 ends to a 100m length of cat 5e cable, tested it with a 9V remote and master tester set, and it seemed fine, all 8 lights shone green. I plugged it into the same wan port of a 4g router in the caravan and there is no signal whatsoever - my device can connect to the 4g router but there is absolutely no bandwidth/transfer of data. 

The cable is not shielded though runs in it’s own underground duct, but in the same trench as a SWA cable in a different duct so over the length of the run the 2 cables are probably pretty close but never touching - however I would expect some data/bandwidth/technical term? to get down the cable rather than nothing at all. 

I have tried switching routers and Ethernet ports but to no avail.

Any ideas how I should proceed to solve the issue and get internet to the caravan router?

Thank you. 

[WSH]

If you are just using the old routers as wireless access points, it's lan port to lan port not wan port.  Also 100m for cat 5e is pushing it.  The 100m spec figure is under lab test conditions with a perfect install & with top quality cable.  Techies usually don't push beyond 85m

[WSH]

I take it the IP addresses are all in the same network?  Probably easiest to disable the DHCPs in the two satellite routers.

[wheeshty]

Thank you for your replies. 

The WAN port is also a LAN port so that should be ok. 

Not sure how to disable DHCP. The same model of router works ok in the office, 40m away, but neither of the 2 satellite routers work at the longer distance. 

Perhaps I’ll try a shielded CAT6 cable over the 100m and see if that’s any better. 

[WSH]

It's unlikely to make any difference as I doubt that's the problem*.  The dual LAN/WAN ports don't usually switch automatically, so make sure it's in LAN mode.  If all three routers have DHCP turned on they'll probably be stuck arguing about who has what address.  You need the one DHCP in a network.  (It is technically possible to have more than one but let's not get complicated).

*Just to clarify.  It doesn't suddenly stop at 100m, it just that the performance goes to ....

[TimCurtis]

When setting up the problem router to test out the cat5e cable just bring it to the main router and connect it via a known working cable. If it then works it's a cable fault.

[pddco]

Could you not simply connect the caravan end of the cable to a PC just to check the cable? Or even an Ethernet switch with some activity / link lights. And does the tester you’ve used identify crossed / incorrect wiring? I’m assuming it must do but very odd that you’re getting no data at all. Just a thought. 

Oh just as an aside. The system has for some reason labelled me an expert. No idea why. I know stuff, and perhaps a bit more than the average. But expert? Perhaps it’s based on the number of replies. Take care out there. 

[wheeshty]

Thank you all. 

PC connected directly to end of caravan cable gets no data and caravan router works in office, so it looks like it’s the cable - even though my cable tester blinks green for all 8 wires within that cable. 

I’ll try new rj45 connectors and if no joy I’ll pull through another slightly better cable and try again. 

Ill report back next week. 

Thanks. 

[WSH]

The trouble with those Wire Map testers (as they are known) is that they tell you if there is a connection but nothing about the quality of the connection.  (You need a Certification tester for that.  A very expensive bit of kit).

It could be a lot of things.  I've seen a case before where an enthusiastic apprentice squeezed the crimp tool too hard.  Cable looked and tested fine but the pins had been pushed in a bit too far to make a good connection in the socket.

On a more serious note, I didn't recognise "SWA cable" when you originally mentioned it and I've since looked it up.  Two points: While twisted pair cable is pretty good at rejecting interference at 230V it's not perfect & a 100m is a hell of long parallel run.  More importantly, I'm not a sparky but I'm pretty sure the safety regs would prevent running network cable and mains down the same duct.  That arrangement may not be safe.

[wheeshty]

hi, I’ll try again with the rj45 and a gentler touch. 

the power cable and cat5e cable are in separate ducts but running in the same trench so they will not be in contact but may run fairly close to each other for some/all of the way.