Cable Forum

Cable Forum (https://www.cableforum.uk/board/index.php)
-   Other Telco Services Discussion (https://www.cableforum.uk/board/forumdisplay.php?f=65)
-   -   Has your phone socket ever caught fire? (https://www.cableforum.uk/board/showthread.php?t=33703883)

RichardCoulter 01-11-2016 01:53

Has your phone socket ever caught fire?
 
A family say that their Sky/Openreach socket caught fire!

Openreach say that this is not possible.

They gave him a temporary mobile internet connection, put in a power surge protector and offered him £120, but say that it must be due to his electric wiring being faulty :confused:

Are dangerous power surges possible or common with telephone lines (with their low voltage)?

Can they actually catch fire?

BBC1 Wales would like anybody who has experienced this to contact them.

The relevant item starts at about 0:13:

http://www.bbc.co.uk/programmes/b080ysbz

rhyds 01-11-2016 09:17

Re: Has your phone socket ever caught fire?
 
I've heard of sockets burning out in lightning strikes, but never as part of a socket/phone wiring fault. There simply isn't the power coming down a line to get it hot enough to burn.

Short some 240v to it however...

heero_yuy 01-11-2016 10:36

Re: Has your phone socket ever caught fire?
 
My mothers phone socket, phone and sky box blew up when there was a local lightning strike on a pole about 200 yds away. The extension lead socket was very charred.

Overhead lines are always vulnerable to strikes or shorts to other cables carrying power especially in high winds, so yes, it could be possible.

Chris 01-11-2016 11:07

Re: Has your phone socket ever caught fire?
 
We got a new iMac out of a lightning strike on our phone line some years ago, pre-wifi when it was hard wired to the modem via Ethernet. iMacs of course have everything on the motherboard, so the insurance company took one look at the repair bill and decided on a new-for-old swap. :D

jb66 01-11-2016 11:44

Re: Has your phone socket ever caught fire?
 
I've seen one during a lightning stike

heero_yuy 01-11-2016 12:20

Re: Has your phone socket ever caught fire?
 
Of course these are exteme examples. In the normal course of events the 48 volt supply on the phone line has very little current available so in itself would have insufficient energy to cause a fire. In fact just taking the phone off the hook drops this to around 24v. It's this action that alerts the exchange to give you a line and the dialing tone.

Paul 01-11-2016 16:12

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by RichardCoulter (Post 35866878)
Are dangerous power surges possible or common with telephone lines (with their low voltage)?

Can they actually catch fire?

The UK Telephone System uses low power (<50mA) at normally 50v (it can be 60v).
You cannot get dangerous power surges from telephone lines (unless they get hit by lightning, or somehow come into contact with a high voltage system, like mains).

RichardCoulter 01-11-2016 16:46

Re: Has your phone socket ever caught fire?
 
Thanks, so it looks like Openreach are correct when they say it's down to faulty wiring in the house ie the telephone wiring has somehow come into contact with the mains wiring :shocked:

jb66 01-11-2016 17:10

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by RichardCoulter (Post 35866995)
Thanks, so it looks like Openreach are correct when they say it's down to faulty wiring in the house ie the telephone wiring has somehow come into contact with the mains wiring :shocked:

If it was through the phoneline it would be melted also

Hugh 01-11-2016 17:58

Re: Has your phone socket ever caught fire?
 
No.

RichardCoulter 01-11-2016 18:56

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by jb66 (Post 35867003)
If it was through the phoneline it would be melted also

That's a point, you'd think that if a power surge occurred on the phone line network that it would never reach a customers home as the wiring would melt long before as it's not designed for high voltages.

---------- Post added at 17:56 ---------- Previous post was at 17:54 ----------

Quote:

Originally Posted by Hugh (Post 35867010)
No.

Why do you say that Hugh?

If there was, say, a lightening strike, wouldn't it melt the Openreach infrastructure before ever getting to the customers home?

I remember that the cable network in the ROI once had problems with something similar though, so (NTL I think) offloaded it.

heero_yuy 01-11-2016 19:17

Re: Has your phone socket ever caught fire?
 
Richard, you have to remember the difference between series mode and common mode. The phone cabling can probably withstand >500v in series mode, that's between conductors, but several thousand volts in common mode, that's from the conductors to other circuits, poles, as in lightning strokes and cable crosses.

Paul 01-11-2016 20:37

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by RichardCoulter (Post 35867026)
Why do you say that Hugh?

If there was, say, a lightening strike, wouldn't it melt the Openreach infrastructure before ever getting to the customers home?

Probably not, its more likely to melt the insulation than the actual copper.

Until quite recently, BT Master sockets had surge protectors in them as well, but they dont use them any more.

Hugh 01-11-2016 20:39

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by RichardCoulter (Post 35867026)
That's a point, you'd think that if a power surge occurred on the phone line network that it would never reach a customers home as the wiring would melt long before as it's not designed for high voltages.

---------- Post added at 17:56 ---------- Previous post was at 17:54 ----------



Why do you say that Hugh?

If there was, say, a lightening strike, wouldn't it melt the Openreach infrastructure before ever getting to the customers home?

I remember that the cable network in the ROI once had problems with something similar though, so (NTL I think) offloaded it.

Your question was
Quote:

Has your phone socket ever caught fire?
No, it hasn't.

pip08456 01-11-2016 20:54

Re: Has your phone socket ever caught fire?
 
Quote:

Originally Posted by RichardCoulter (Post 35866995)
Thanks, so it looks like Openreach are correct when they say it's down to faulty wiring in the house ie the telephone wiring has somehow come into contact with the mains wiring :shocked:

I should imaging Openreach know there were no lightening strikes ATT. There are regulations regarding the routing of electrical curcuits, telephone and ethernet circuits in the home and minimum distances between each to mitigate the chance of a short.


All times are GMT +1. The time now is 23:26.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.