Re routing VM cable from old BT system

[paul243]

My VM phone cable goes from the external VM brown box up two stories to an old BT junction box in a bedroom (not to router so old install I presume).The cables then go around the house to several old sockets, including one to my Gigaset base via a plug in socket.  As I am now using 5 DECT phones the old cables are redundant. The incoming BT cable was cut during the VM install. Can I now simply connect one new cable from the external box to my Gigaset base (the cable is in poor condition) and remove all the old cables, or are there any components in the BT junction which are still required.?

Thanks

Paul

[goslow · Accepted solution]

It's not uncommon for VM to have linked in to previous BT wiring in the past. If you are wanting to rationalise your phone wiring, and you are on the old standard connection via telephone wall sockets, then VM should provide you with a single VM master socket from the external omnibox. The master socket does contain some additional components. From the master socket you can connect your own extensions. VM may possibly have reused the BT master socket. A VM or BT master socket should be identifiable by having a small, lower faceplate on the front which is removable.

If you don't have a VM master socket, VM should provide you with one. If you just need the phone wiring modifying to a different arrangement then VM will do that for a standard £25 fee.

They may possibly offer to convert you to a phone connection from the back of the hub (where everyone will end up by 2025). That should work OK with your cordless phones but, if they offer that to you, check out some of the other limitations such as the line not working during power cuts or hub outages before deciding whether to go down that route.

[paul243]

Thanks for prompt reply,

Can I not simply remove the VM cable from the old BT box, bring it to  ground level, take it around the house and connect to the Gigaset DECT base, extending with a weatherproof junction and jelly crimps if needed? Therefore enabling me to remove all old external and internal cabling and boxes/sockets

I'm trying to avoid cables rising up 30 feet to come down again to supply the DECT base. And to remove old boxes.
Is a master socket need for DECT phones, what does it do?

Thanks

[goslow]

The phone provider is responsible for the line to the house and a master socket on the end of the phone line.

The traditional master socket contains several extra components: a ringing capacitor (now largely unnecessary for modern phones), a surge arrestor (to protect against voltage spikes on the line) and a test resistor (to allow remote tests to be run on the line). BT have modified this design over time for changes in broadband connection/type over the phone line. Doubt VM will have done so as no broadband is carried on the phone line. VM's T&Cs preclude customers making any changes to VM's equipment (phone cabling up to and inc. the master phone socket and any coax cabling/wall boxes). You can, however, fit your own phone extensions from the master socket.

The master socket has a removable faceplate at the bottom. The customer can connect extension sockets from the faceplate. The faceplate can be removed which also disconnects the extension sockets from the master socket. The purpose of this is for fault finding in case extension sockets (the responsibility of the customer) are causing a fault on the line.

If you happen to have a collection of jelly crimps, spare external grade phone wire and a master socket etc. hanging around, then I guess you could save yourself some money via a DIY approach. If not, and you have to buy this stuff, then you could be well on your way to spending the £25 for the VM fee to get a master socket fitted where you want it. Also if VM do the installation you won't have to explain any DIY work in the future if that ever became an issue.

Worth noting that, at some point before 2025, everyone will be moving to a phone connection from the back of the hub in which case your phone wiring will become redundant. I think I read a comment on here from one of the forum team that VM’s target is actually the end of 2022. So, if hub placement, as well as phone placement, has any relevance then you might want to factor that in too as part of any wiring changes.

If it was me, I'd pay VM the £25 to put a new single master socket where you want it. You can then remove all the redundant extension wiring at your leisure.

[paul243]

Many thanks, very informative.

[paul243]

Update.

The VM line from the brown external box does go to a master ,2 piece socket a few feet away in a downstairs room. Marked "Cable and Wireless"

A cable then goes to the bedroom socket which looks like a normal socket but which has components on the front plate, so I presume another master? Marked "T"

From here cables go to bedrooms and one to the Gigaset base 25metres around the  house . I only need this one cable to the base, so can I go from the ground floor master to the base , bypassing the first floor socket. I have cable and crimps etc .

Thanks

[goslow]

If you have a C&W master socket with a removable faceplate for extension wiring, then you can legitimately connect an extension socket from that master socket removable faceplate to wherever you want it. The extension will be a 'secondary' socket and will have no components on the back of it, unlike the master. You could probably recycle a secondary socket from the collection of old wiring that you will be removing if it is in good, working condition.

There are loads of online how-to's on wiring telephone extension sockets from a master but this video is comprehensive.

https://www.youtube.com/watch?v=h6TqFcAOIcM&ab_channel=MyMateVINCE

I believe the guy is a former BT installation tech.

[paul243]

Thanks again Goslow, appreciate your help. Great video.

One more query please, can I now discard the old "master" in the bedroom as I have the CW master fed from the VM box?. So take my new cable from that direct to my Gigaset base.

HNY

[goslow]

Yes, you should only have one master socket per line/installation. I imagine when your C&W/VM connection was put into use, they installed the C&W master socket and then simply linked it to whatever else you already had in the house (presumably including the old master socket from the former BT line) to make all of the sockets in the house live on the C&W/VM phone line. (I am assuming you now only have a phone service from VM and no separate BT line anywhere to consider).

If I have understood your descriptions correctly you would end up with

Brown VM omnibox outside>> Already wired to an existing C&W master socket>> New secondary extension cable/socket in the new location wired via the removable faceplate from the C&W master.

The whole point of the removable extension faceplate on the master socket is that if you make a mistake with the extension wiring, and it doesn't work, you can just remove the extension faceplate and that totally disconnects the extension wiring which should leave you just with a working master socket.

Usual extension errors are mixing a wire pair/colour or not pressing down the wire hard/far enough into the IDC connector. The plastic IDC tools provided in kits for this only usually work reliably for a couple of goes.