Electrifying

[Feltwell]

There was I yesterday, convincing the neighbours that I really do need certifying, wandering around outside in a torrential downpour with an umbrella looking up at the roof and checking the guttering and downpipes are all functioning OK, when I noticed the ground was sparking - distinct sparks, and little puffs of smoke, coming from one spot.

So today, knowing that the mains cable that comes into the house is not there, I gingerly dug up said spot and found what I believe is the culprit. The previous people here had Sky TV and telephone, what I've found is the underground cable to serve that, which has been severed.

Having deferred to the Great God of Google, I've found on a few AV forums people complaining of sparks when they hook the cables up to their expensive kit inside the house, it seems these cables do carry about 90 volts, although very little current. So, satisfied that it's safe although still not terribly keen to start fondling the end of the cable, my thoughts turn to how best to cap it off to stop the slightly disconcerting pyrotechnic display when it rains.

Any ideas? I could stick a bit of heatshrink tubing over the end and sticking out a bit, shrink it, fold the excess back over the cable end then put another bit of heatshrink on to seal that.

I did think of a resin joint kit as on the link below, but it seems a bit OTT (and I'm too mean to spend the £11 ! )

http://www.ebay.co.uk/itm/Resin-Und...al_Components_Supplies_ET&hash=item232aac7492

 

[Lime]

I think the comments in AV forums are more to do with a TV having static on its aerial lead rather than the sky cable carrying any voltage.
The Sky cable is just acting as an earth.
With some TVs, particularly those with a CRT, it is/was common for the aerial connection on the TV to have a high voltage present.
In theory the connection should be "floating" i.e. not earthed but with some TVs the internal aerial wiring picks up voltage from the circuits within the TV.

I'd contact Sky.
You are right to be careful.
I wouldn't touch it. (and I'm an old hand with electrics)


This reminds me of when I was walking the perimeter of the National Trust field my wife rented for her horse several years ago.
I came across an old cable and broken connector box lying half-buried on the ground.
It looked to me like a electricity board supply cable for a meter and since the terminals were exposed (and horses have metal shoes) I thought I'd best check that it was disconnected.
Fortunately I carry a multimeter in my Land Rover so I tested it.
It was live!

I telephoned the National Trust and they had the cable disconnected by the electricity board in the street.
Apparently it used to supply a piggery in the field (knocked down a long time ago) and the cable had laid there ever since.
I shudder to think what would have happened if a shod horse had stood on it, bearing in mind the cable would have had the minimum of an 800 amp fuse supplying it.

 

[Flyfisher]

I'd contact Sky.
You are right to be careful.
I wouldn't touch it. (and I'm an old hand with electrics)

I agree. I can understand there being a voltage present but if the cable is capable of generating puffs of smoke as well then that suggests to me a reasonable amount of power as well.

I'd say you've done your bit in tracing the problem but it's really the responsibility of the service provider to make it permanently safe.

 

[Zebra]

Yes, and equines (and other large quadrupeds) can be more susceptible to electric shock than you humans, due to being larger conductors, earthed at the other end.

Feltwell, your solution sounds fine. Anything else is probably over the top. I'd also contact Sky, as Lime says.

 

[Owain]

It's possible for people to get small sparks when plugging/unplugging equipment with different potentials on the wires. You can get a spark off a 9v battery.

However I do not think that the 90v on a Sky cable would be causing puffs of smoke out of the ground.

I think it's much more likely that there's a damaged live mains cable under there and if it's not the 240/415 volt one feeding your house it could be a local distributor at 3kV or 6kV

Please contact your DNO emergency line as a matter of urgency and do not attempt to repair this yourself.

(A photo would be good though)

 

[Feltwell]

I'm trying to contact Sky now, think I'm confusing them as I haven't got an account with them! Call centres, don't you just love them..........

 

[Feltwell]

It's OK Owain, I'm sure it's not mains.

The cable supplying my house enters a good way away from the spot concerned, I've seen it when I've been crawling around under the lounge floor in the cavity, putting insulation in.

It's highly unlikely to be any other mains cable, as the house was built well before mains power came to the town - and to be at that spot means the cable would be passing under the house.

The cut cable I've uncovered is no thicker than a co-ax cable and has what looks like a telephone cable jointed to it, running alongside it. You can see where it went into the house - the Sky engineer having drilled through from inside and damaged the brickwork externally... :evil:

The sparks are minor and are only really visible in low light. The puff of smoke is a little more worrying, but then I've seen motorbike wiring connected to nothing more than a small 6 volt battery smoke!

Sky's "online chat" person couldn't help and referred me to a phone number for a "Field Escalation " team, which takes me to one of those lovely multi-menu systems which eventually told me I've got at least a half hour wait to get connected to a human. I think I'll try during the week, early one morning! For now I'll stick some heatshrink over it, whilst wearing rubber gloves!

 

[Owain]

If it's figure-of-8 cable with coax one side and wires the other it could be Virgin cable connection or a cable to a CCTV camera?

If CCTV then could have 24Vac at several amps on it, that's enough to cause a hefty current to flow if it's shorted.

 

[Feltwell]

Could be Virgin - I thought the previous people had Sky, but it may have been Virgin, they certainly pester us enough to join them, we get bumpf addressed to "The Occupier" at least once a month. Hmmm - the fact we're on their database like that makes it more likely that it was Virgin actually, thanks for that. Definitely not CCTV.

I've capped it off with heat-shrink, all safe for now and I've a new hair style to boot.

 

[worms]

Am I the only one to wonder if it would be possible to connect something up to it and get free electricity courtesy of Sky?

 

[LadyArowana]

Am I the only one to wonder if it would be possible to connect something up to it and get free electricity courtesy of Sky?

I was wondering about free TV programmes :lol: Not that I can complain, I don't have a TV in London, but can get things on the i.Player as my BTWiFi is good enough for video. Good enough in very specific places in the apartment, one of which happily is to have the laptop on the bed, very snuggly.

 

[chuckey]

Years ago I saw white smoke or steam coming out of a Post office telephone pole mounted box beyond the end of my garden (so greater then 120 feet away), I phoned the engineers on 150 and basically got nowhere. I don't think they ever turned out to fix the problem. The thing that confuses me is that the exchange provides 50 volts at a maximum current of about .012 A, so the maximum power available would be .3 of a watt, you would not get much of a fire with level of power!
Frank

 

[Zebra]

it may have been Virgin, they certainly pester us enough to join them, we get bumpf addressed to "The Occupier" at least once a month.

That means nothing, I feel sure - I get that stuff too, and I don't have a telly, the house was empty for two years before I bought it, and an old lady lived here before then who I'm sure didn't have cable TV!

 

[LadyArowana]

I get immense quantities of junk mail from Virgin and Sky and BT Broadband. There hasn't been a TV here for nearly 25 years and there has never ever been any of the cable services. I also get nasty threatening things from the TV licensing people, which I ignore.