Advice wanted - unhappy with rewire

[Kojak]

Call building control at your local council, tell them whats happend and ask how to enforce your consumer rights.

 

[telectrix]

I've wanted to know how putting the RFC cpc's in separate earth terminals, assist in high integrity earthing, if someone could help me out.

ssssimplees it's in case 1 falls out due to incompetent installation.

 

[telectrix]

My reason is common sense most electronic devices use switchmode transformers which filter to earth .The regs state " which can be reasonably be expected to exceed 10ma " .Well it's your choice mate .But considering socket outlets come with two terminals !
It appears you have over reacted to a quite Justified statement .It wasn't meant as an insult to your work sorry if you took it that way . 543.7.2 ( 18 )

no offence taken, but you should research as to why the cpcs should be separated betweed 2 terminals.

 

[Stuey]

I've wanted to know how putting the RFC cpc's in separate earth terminals, assist in high integrity earthing, if someone could help me out.

no offence taken, but you should research as to why the cpcs should be separated betweed 2 terminals.

Again no offence meant .But I have .This has become more of an issue in domestic Installations with the popularity in Led lighting and other newer electronic devices now using filtered PSU's . The main point is safety due to possible earth current transfer from device to device either resulting in capacitor induced shock or even fire . As someone else has stated this can result from a bad connection either by a high resistance connection, mechanical damage or possible capacitor failure within the device itself .

 

[AJshep]

There is no need to seperate earth terminals on a Domestic install. You are right Stuey in what you say but lets not take things to the extreme.
This sounds like regurgitated carp from some college lecturer.
Switching PSUs are a slight problem we are all aware DC equipment has a higher earth leakage but how many does the average house have ?
Do you know how this installation is used by looking at a picture ? This install could be a elderly couple house, not a hackers house with multiple USB sockets and PSUs plugged in.
Led lighting is not usually applicable to either as this on the lighting circuit.

Lets not jump in and insult someones work, leave all this rubbish to the Facebook groups

 

[richy3333]

I hope this isn't one of yours ! Ring main Earths are one cable per terminal not two as in your picture

It’s not a fudging ring main!

 

[John Arnold]

What a terrible installation. Massive holes made for sockets really bad looks like they used an angle grinder to cut those and damaged the skirting board to. Height of consumer unit far too low eye level please. Where is the covering protection over the wiring?telectrix so right mate. That loose wire has no screw markings on it I guess it was not secured?You have my sympathy I hope they come back and correct their faults and give you your certificate( do not hold your breath).

 

[holychihuahua]

I have seen that type of plug burn before. When a plug on a small fan heater gets stood on and brocken any plug to hand is fitted on the heater as a replacement. The trouble is the replacement plug is not the same grade of plastic as the original and melts. That burn damage is on the builder or plasterer not the electrican.

 

[Astris]

Interesting to note the various comments from working electricians ... not a consistent set of comments. I think the polite ones are valid and illustrate that there is room for interpretation. One man's masterpiece is another man's pile of ****!
Are the metal boxes earthed?
Sharing or not sharing earth terminals on a ring cpc is something of a red herring in this context. I think that the reason that high integrity earths are run separately is because computer and other similar equipment (including switched mode PSUs) use filters to meet RFI specifications (to control imported and exported RF noise). They employ filters that connect reactive components (capacitors and inductors) between line conductors and the cpc and this can induce RF currents in the cpc cable linking the equipment to the system ground point. If we really care about controlling RF noise, we should avoid the use of any ring circuits at all and have one system ground point to which all cpcs are connected directly to the ground point in a star network.

 

[telectrix]

the purpose of separating the cpc's into separate terminals is in case 1 becomes loose or snapped, you'll still have earthing (protective and functional) to equipment .

 

[Astris]

the purpose of separating the cpc's into separate terminals is in case 1 becomes loose or snapped, you'll still have earthing (protective and functional) to equipment .

Yes, I understand what you are saying and don't dispute the point. If you think about it, one or two terminals can suffer the same fate.

I was trying to explain why problems can occur with RCD protection on modern equipment (e.g. computers with switched mode PSUs drawing several amps at 230V) - by design, current will flow through the cpc and unbalance the RCD. Not everybody understands that.

 

[telectrix]

agree with some leakage on IT eqwuipment, but each item should typically have a leakage current of 3 - 4 mA. this will only upset a RCD if too many items are on 1 RCD.

 

[AJshep]

Yes, I understand what you are saying and don't dispute the point. If you think about it, one or two terminals can suffer the same fate.

I was trying to explain why problems can occur with RCD protection on modern equipment (e.g. computers with switched mode PSUs drawing several amps at 230V) - by design, current will flow through the cpc and unbalance the RCD. Not everybody understands that.

I think this is maybe what Stuey was getting at when he stated 543.7.2 but this is a separate issue. We generally work through the regs book and earth leakage is mentioned previously in 531.3.2 , we should select the correct type of RCD for the installation as per 531.3.4

You are right in what you say, this is becoming more of an issue.
But on the other hand this is different issue to putting two CPC of a Domestic RFC in the same terminal, especially where most of the switching PSUs will most likely be small types like phone chargers which are mostly double insulated phone chargers.

 

[Pete999]

We are talking about high integrity earthing are we not? I'll wait for an answer before I carry on, if that's OK.

 

[Astris]

We are talking about high integrity earthing are we not? I'll wait for an answer before I carry on, if that's OK.

Probably should continue under a new thread?

 

[Astris]

But on the other hand this is different issue to putting two CPC of a Domestic RFC in the same terminal, especially where most of the switching PSUs will most likely be small types like phone chargers which are mostly double insulated phone chargers.

Yes, I agree.

Would you consider a domestic installation as unlikely to need consideration for high integrity earthing unless there is a specific reason (e.g. medical equipment)?

 

[Pete999]

Yes, I agree.

Would you consider a domestic installation as unlikely to need consideration for high integrity earthing unless there is a specific reason (e.g. medical equipment)?

No not unless the copulative earth leakage current exceeded 10mA Regulation 543.7.1

 

[DPG]

Copulative leakage. Brill

 

[Pete999]

Copulative leakage. Brill

For that read cumulative, predictive text, my foot sorry all for the gaff.

 

[ruston]

Copulative leakage. Brill

I have an answer for that but I have never had a warning so far.