Insulation Testing Problems

[bigbaddave]

Been to a job last week, Rcd tripping when its raining. Global IR 0.042. Tested 250v (L&N) cpc to save taken out all the lamps. TV's on walls were isolated via fused spur.

Problem located on External light therefore retested (L/N - CPC).. No test beetween (L&n was done)

I have now been told that the TV on the wall is not working as they are getting white flash and they have come to the conclusion that is me testing that has caused it.. Now if 500v (L-n) had been applied then yes fair enough..

Im struggling to see how this is the cause but they are seeking a response..

 

[Guest55]

well if you isolated the tv spurs when testing then you cant have damaged them ?

 

[KAS1]

Your testing would not effect the TV, as the spur is a double pole switch the TV would of been isolated assuming you had switched it off.

 

[bigbaddave]

Thats exactly my though.. The only assumption that was made was the spur actually worked the TV.

On the other note though.. Surley L&N - cpc by passed the load therefore another reason to why this should not be the cause

 

[Toonlad]

Was the tv actually on when you isolated, heard of cases people blagging new tvs this way. Used to happen frequently with a small firm i used to work for.

 

[rattlehead85]

Unfortunately people with electronic equipment that is known to be problematic to them will always blame the poor sparky once he steps foot inside the door. Advice is to get a disclaimer signed first covering you before you carry out any work. The client may well have already been flickin'' through their electrical catalogue choosing a new top of the shop tele which they will be approaching you to contribute towards.

 

[Guest55]

it doesnt matter what testing you did.
its up to the homeowner to prove you did the damage if he wants to claim.
and even a simple defect report from a tv repairman will cost them £50-60.
call their bluff and do nowt.

 

[Brightspark2]

Your testing would not effect the TV, as the spur is a double pole switch the TV would of been isolated assuming you had switched it off.

Not all are double pole...

 

[Clive P]

Hi,

Do they have a TV Amplifier on that circuit that may be causing the problem at the TV, rather than a TV fault?

Regards.

 

[bigbaddave]

Hi,

Do they have a TV Amplifier on that circuit that may be causing the problem at the TV, rather than a TV fault?

Regards.

Everything does work not just the TV, Sat Dvd Etc .

Even if it wasnt DP then surley L&n - cpc couldn't fry the Tv. Could it?

 

[bigbaddave]

Was the tv actually on when you isolated, heard of cases people blagging new tvs this way. Used to happen frequently with a small firm i used to work for.

Pass on this one im affraid..

 

[Paul.M]

Please correct me if I'm wrong but:- Testing a circuit at 250V DC regardless of the fsu on/off, single or double pole would not damage the tv if testing l+N to CPC.

Dave they are trying it on mate, stand your ground on this one and dont put your hand in your pocket to pay for a new tv for them.

 

[KAS1]

Why would this be a single pole fused spur, it's being used as a fused switch / isolator to a TV from a ring main, that would not make any sense to use a switched single pole fused spur flex outlet ?????

Not all are double pole...

 

[bigbaddave]

Why would this be a single pole fused spur, it's being used as a fused switch / isolator to a TV from a ring main, that would not make any sense to use a switched single pole fused spur flex outlet ?????

There is shed loads of installs i have been to that dont make any sence.. Like the shower someone had decided to spur off the ringmain..

 

[Brightspark2]

Why would this be a single pole fused spur, it's being used as a fused switch / isolator to a TV from a ring main, that would not make any sense to use a switched single pole fused spur flex outlet ?????

Like big Dave says a lot of things dont make sense...

Depends on who did the job...

 

[MDJ]

Everything does work not just the TV, Sat Dvd Etc .

Even if it wasnt DP then surley L&n - cpc couldn't fry the Tv. Could it?

If it is a modern Flat screen TV then there should be a surge protection device in the back and it will be internally fused??

 

[Paul.M]

Not all switched fused spur units are DP. An SP unit can be used on a tv like above and a DP unit must be used for boilers etc. Lets not assume its a DP on this telly but it still would not make a difference at 250V DC.

 

[moose]

I know its common practice to use a lesser voltage, but you should be using 500v, if you turn back time use 1000v just for the luck the TV breaks hehe....