Static on coaxial cable

Payton

Hi, I have a connection from the junction box under the eaves of the house through UPC going into the attic where I have a 4 way splitter dropping cables down to the bedrooms, as Im running new cable to my daughters bedroom and was about to put the connection on for the back of the TV when I got a small static shock :eek: The picture is perfect on all the TV's and there are no powered booster in the attic just a 4 way splitter. Where would the static be from?

lucernarian

I don't quite understand how it works but the shielding of the cable and the metal chassis of boxes (DVD player, STB etc) can act as a "floating neutral". So the outer case of these non-earthed boxes carries a transient voltage of half the mains. But as it's so transient, there's practically no current when this voltage is grounded. So while you might feel it, the current is so tiny that it's quite safe.

While that's the most likely explanation, I think a call out from UPC would be necessary to ensure that no unfortunate contact with mains cables has happened. You can get a small shock from mains in one set of footwear for example and then be struck dead with touching the same wire while wearing different shoes. I don't think it's worth taking such a risk with cables coming in from outside your house.

Payton

Thanks, but the cable is running from the junction box under the eaves to a splitter and then to the tv's and not in contact with any mains cable or did player/stb I do have a socket in the attic and I might run an earth wire from the splitter to socket and see if that works. Calling UPC out would only incur a charge per connection per month....

lucernarian

on the verge wrote: »

Thanks, but the cable is running from the junction box under the eaves to a splitter and then to the tv's and not in contact with any mains cable or did player/stb I do have a socket in the attic and I might run an earth wire from the splitter to socket and see if that works. Calling UPC out would only incur a charge per connection per month....

You're not getting me, the UPC cable could well be in contact with ESB cables outside. I know with my house, the UPC cable and ESB cable run alongside each other outside my house and for a further 50 metres too. Also, you're not supposed to earth objects not connected in some way to the mains with an earth wire that's used for the mains electricity in the house. I don't know the reasons why but it's something that an electrician would have to advise you on. Regarding shocks from the UPC cable, there are things they can do to stop any residual electricity coming in from outside which is the main safety concern here. I suggest you contact UPC if you are still concerned about the shocks from plugs coming from the splitter or wherever.

zg3409

I have gotten slight shock's from UPC forever. It's just static, nothing to worry about. If it was live you would have got a jolt rather than a tingle or crack.

Long cables pick up static, that's what happens.