Fault on RCD Trip

[steptoe]

So then whats the situation here that relates to RCD tripping?And what can be done?

IMHO, and it is often wrong,

I think the answer is to TT Mr faultmans house

I think that is the easy answer

 

[Sidewinder]

As Steps said earlier we are not going to get to the bottom of this on here.

I suspect that it is a DNO issue with a broken or damaged CNE conductor from the info so far.

Any other comments?

One issue I'm not sure about is whether the OP & the neignbour are on the same phase, this could help to explain the situation either way.

 

[sparkytim]

It sounds likely they are on same phase as its 2 doors away i.e. 4 Houses in row 2 of them HAVE to be.

So if one shows HIGH Ze in comparison with other three (DNO cable fault)then do you suggest this could cause the problem?

 

[Sidewinder]

Could be, but on site tests would have to be done, and a long wander lead may be useful!

 

[sparkytim]

What other tests would you suggest?

 

[Sidewinder]

Need to see the two installs and get an understanding of the sockets being used, are they actually PME installs and so more before commenting on what is actually required.

You would need to assess which phase the 2 properties are on.

The protective devices in use, the location of any PME rods in the area, they are quite easy to find once you know how, I have been luck in having a lesson off one of my local DNO guys.

And and and...

 

[Theorysparky]

Need to see the two installs and get an understanding of the sockets being used, are they actually PME installs and so more before commenting on what is actually required.You would need to assess which phase the 2 properties are on.

The protective devices in use, the location of any PME rods in the area, they are quite easy to find once you know how, I have been luck in having a lesson off one of my local DNO guys.

And and and...

and......

 

[sparkytim]

Just trying to see how we might help OP to prove to DNO THEY NEED to sort it and rule out any other possibility.

 

[Sidewinder]

TT their supply as an experiment may be a simple test?

 

[a1]

this is getting ridiculous, its almost as bad at work sometimes when I get frustrated then I start talking fast and dropping into my local lingo and on occasion someone has to translate for me then too.!!! headbang

PMSL. That reminds me -I was talking to our 'Sandra' on the phone Yesterday.

There was a lot of pauses on his behalf. He didn't have a clue what I was on about. I do believe ElectekAir had the same problem, the other week too.

If anyone else meets me, They will have to have subtitles. :^O

 

[a1]

Do you think that MrLawnmower Man will allow his System to be TT'd? Would he pay up to do it?

Well done Gents. It's great to see another nice and friendly debate turn into something very useful.

Mr Winder - I will look at your two explanatory posts in detail Tomorrow. My eyes are dropping off at present.

 

[sparkytim]

Looks like its Bed time then

:good night:

 

[Sidewinder]

Me too in a minute or so!

:good night:

Paul

 

[Theorysparky]

:good night: :z

 

[steptoe]

IMHO, and it is often wrong,I think the answer is to TT Mr faultmans house

I think that is the easy answer

]TT their supply as an experiment may be a simple test?

would that be another heads up to one of my suggestions?

 

[ADS]

I totally disagree with what is being suggested here and would love to argue my point - but I've been told I'm not allowed to!

Dear ADS,

You have received an infraction at Electrician Forum.

Reason: Arguing on forum (Pretty Regularly)

-------

If you don't get on with certain Members please refrain from arguing with them. Please ingore that person.

And the same applies the other way around.

Please remember that further infractions will lead to a Ban from the forum.

Best Regards,

Admin.

-------

This infraction is worth 15 point(s) and may result in restricted access until it expires. Serious infractions will never expire.

Unlike some posters, I have kept my points simple and on-topic, and have not made personal or degrading comments to anyone, yet I have been threatened with being banned.

If that's what you want - a forum where people just believe any old tripe that's trotted out to them, with everyone scared to say 'boo' for fear of upsetting a select few, then good luck to you!

I take it I'm entitled to this opinion?

 

[kme]

You`re entitled to any opinion mate, same as everyone else.

TBH, I`m not getting into forum politics - I`m just a sparx

What I will say was that I thought you were a little confrontational with the warlier post -

Perhaps it isn`t the opinion that was objected to; more the attitude with which it was delivered?

Personally, I like your input on things, as I like many other peoples input. But you can come over a little aggressive with the posts at times, mate.

Please note: I may be completely wrong; this is just my opinion. Don`t take offence, FCOL.

KME

 

[SPECIAL LOCATION]

And where exactly is this backfed current going when heading up his incomming neutral and through his RCD - bearing in mind basic circuit theory

Basic current theory....?

This is what were were taught in college....

maybe they don't teach it anymore?

but for the benefit of others who haven't grasped 3-phase generation..

Or who are still at college and only just getting their heads around this stuff..

Heres the short Spec Loc layman's guide....

Ignore earths for a bit...

just consider the circuit current flowing in correctly connected systems..

Part(a) The 3-phase how its generated bit....

1a/

Electricwery is generated as '3-PHASE' connected with a common neutral star point.

2a/

A 3-PHASE supply can be used to supply 3-phase loads in Star or Delta wiring configurations.

3a/

Star connected loads use a fourth neutral conductor back to the star point.

4a/

Delta connected loads have NO neutral.....

(so this magic electricity is just going up and down the 3 individual phase conductors.. in a very pretty sinusoidal pattern offset by about 120 degrees!)

5a/

Assuming you can understand the concept of Star & Delta loads you will be able to grasp that current can flow between phases with NO neutral connections.

Part(B) The single phase load tapped off a 3-phase supply.

1b/

A 3-Phase supply can be used to supply single phase loads using one of the phases down to the common neutral star point.

2b/

Our domestic homes are individual "unbalanced" loads across one of the phases.

3b/

You could take a simple illustration considering three properties each as being on a separate phase but back to a common neutral (star point)

4b/

If two properties supplied from different phases have a path down their neutrals connected to each other but it is broken somewhere going back to the supply star point.. (maybe via a multiple earth point nearer to adjoining property than the supplier earth points) Those two properties can effectively become two sides of a Delta wiring arrangement..

5b/

Properties configured as delta wiring are bad news cuz of the potential of a 400v difference across the supply cables coming into the property..

6b/

I had a property last year where a neutral break in the street blew up their Washing machine, Security Alarm, and something else.. but I cant remember what it was...

Obviously a single phase open circuit don't produce enough voltage to blow up the washing machine..

But.... "PME/TNC-S/PME/TNC-S/PME/TNC-S" * .. can produce these sort of problems.

(delete as you feel appropriate and which is you preferred name of choice but don't bother saying they are not the same!)

5b/

The earth arrangement can provide virtual (or high res) paths between properties to extenuate the above symptoms in supply fault conditions.

SO...

Bottom line is current CAN go back up a 'neutral' leg of a supply cable..

If that 'neutral' leg is now part of a join between two loads on different phases with 'No' or a 'Very high Resistance' path back to the supply Star point.

I believe this is the sort of "Basics" that steptoe alludes to and gets frustrated about when people cannot grasp basic electrical supply...

and when they seem to imply that domestic properties are just a completely individual Single phase load from a single phase generated supply with separate Line Neutral And Earth conductors coming all the way from the power station to your home!! with NO interrelation to any adjoining properties!

:|

Does any of that make sense?

or am I talking out me pants again?

:|

 

[Watchdog]

I totally disagree with what is being suggested here and would love to argue my point - but I've been told I'm not allowed to!Unlike some posters, I have kept my points simple and on-topic, and have not made personal or degrading comments to anyone, yet I have been threatened with being banned.

If that's what you want - a forum where people just believe any old tripe that's trotted out to them, with everyone scared to say 'boo' for fear of upsetting a select few, then good luck to you!

I take it I'm entitled to this opinion?

There is a huge difference between discussing and arguing.

A much better method than direct confrontation is coming up with an argument so watertight that there is no doubt over who has the better argument.

If we all agreed on everything it wouldn't be much of a discussion forum.

Everyone is entitled to their opinion, but sometimes it is better in life to keep it to yourself.

We have said before - we will not tolerate personal remarks.

 

[ADS]

Once again, Specs, totally agree with your description of things - you have no argument from me on any of you points in the previous post

My argument was that no current will flow through the OPs RCD from the supply side neutral (thereby causing an imballance and tripping) as it's not got anywhere further to go.

Current flowing up a shared supply neutral is an acceptable idea, because (in TN-C-S), that neutral is connected to the MET - giving parallel paths to earth via the consumers bonding- in other words completing a circuit back to the transformer.

But this isn't the case on the customer side of the RCD, so it's not gonna flow through the RCD to cause an imballance - unless, as I said earlier, there was a neutral/earth fault on the final circuit, giving a path to earth again.

Surely this makes sense??

And KME,

Perhaps it isn`t the opinion that was objected to; more the attitude with which it was delivered? Personally, I like your input on things, as I like many other peoples input. But you can come over a little aggressive with the posts at times, mate.

KME

The reason is that a lot of the time my points are ignored or belittled, with no actual reply to what I have said - I'm just ****ged off because I don't agree with certain people.

This is when the frustration comes out

Watchdog,

A much better method than direct confrontation is coming up with an argument so watertight that there is no doubt over who has the better argument.

I have done this in previous posts on other topics - I've gone out of my way to back up my statements with fact and evidence - that's when comments get personal towards me, when they have no true argument back.