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[tuftedduck]

I have just read this thread over at CA forum  http://forums.computeractive.co.uk/showthread.php?p=1251854#post1251854 and was interested in the post by Tekman591 who states :-

Quote " during many weeks dealing with the companies i have learnt a few tricks like check using volt meter across both input wires at the back of the master socket should read 48.8 volts AC, if reading different then theres a problem with phone line if is ok then start checking wiring from main socket . " Unquote

Is that an accurate statement ?

[roseway]

No, it's not correct. The normal voltage across the incoming wires is 50 volts DC (not AC), and when the phone is ringing it's 75 volts AC.

[tuftedduck]

Thank you.

[waltergmw]

Gentlefolk,

On a Virgin line using a digital volt meter I've measured about 85 Volts on-hook, but out of interest I'll check again this evening. when I get home.

Kind reagrds,
Walter

[silversurfer44]

I know it's a bit of a kick when someone rings in and you have your fingers across the wires.!

[waltergmw]

Apologies all,

I had forgotten to test my Virgin Media line which I've now done.

Using a digital volt meter the on-hook DC voltage ranges from 79 to 85 Volts and when off-hook it is constant at 19.9 Volts.

Kind regards,
Walter

[razpag]

No, it's not correct. The normal voltage across the incoming wires is 50 volts DC (not AC), and when the phone is ringing it's 75 volts AC.

It can actually be as much as 120Vac when ringing (On an Openreach circuit). Absolutely love it when testing a circuit at the top of a pole in the pouring rain !!!!!!!!!! Not !!!!!!!!!

[silversurfer44]

Have you got curly hair razpag ? 

[waltergmw]

@ razpag,

I know you're dealing with difficult knitting but try following the hot line power workers rules carved in stone:-

Only work on a single phase or neutral at one time and make sure you don't bridge the supply to the distribution sides through your body !

Kind regards,
Walter

[razpag]

LOL Walter .... thanks for the thought pal, but as a time-served spark I'm pretty much aware of current flow.

The problem is that when touching just the 'live' wire, the ringing current tracks through your body to earth. A thousand times more when you are soaking wet and ones body resistance is quite low. Unlike 'Power line hot workers', we cant wear 11Kva insulated gloves and stand on a rubber mat in rubber wellies when stood at the top of a telegraph pole. Wish we bloody could though !!

Silversurfer .....  not curly, but greying by the minute pal.

[waltergmw]

@ razpak,

I used to swear at the time, but there was a good reason for humping around heavy wooden ladders, if not using climbing spikes (on dead circuits).
High voltage gloves were so thick you couldn't even pick up a cup of tea !
The best solution was to use ordinary leather gloves so you weren't burnt, put the jumper into the bottom of the line tap and jam it on to the live line as fast as you could !

The fun part was cutting through a 3 Kv coaxial outer, even with the power off there were spectacular earth currents.
Or perhaps spiking through the return core of a large and unknown DC twin cable leaving the live intact ! After that, we decided to double spike at right angles.

That's enough of "war stories" !

Kind regards,
Walter

[razpag]

Wow .... mad stuff Walter. The worst that can happen to us is in everyday life, is as I've mentioned earlier in this thread. Basically a bit of a wake-up call.

Having said that, there are occasions (few and far between) where Mr DIY has managed to apply mains voltage to our network by connecting 240v to a telephone socket. Or running a piece of twin and earth under a carpet and getting it (and our cable) trapped on the gripper rods, thus again applying 240v to our network.

Nothing like what you had to work with Walter.

[BritBrat]

Someone where I used to work was stealing some redundant cable (3" Dia) and cutting it with a hacksaw.

Turned out it was not redundant and it was the last thing he attempted to steal.

[silversurfer44]

I bet that came as a shock to him. 

[razpag]

Someone where I used to work was stealing some redundant cable (3" Dia) and cutting it with a hacksaw.

Turned out it was not redundant and it was the last thing he attempted to steal.

he he he ...  ............ you'd think the fools would invest in a 'Voltage Neon-Indicator'.