**CU Changes And YOU**

[oldtimer]

Just to sober everyone up here in Glasgow today a Sherif found a "handyman" at fault for the death of a 21 month old toddler after the child put a "disconnected" oven supply cable in his mouth so heres the deal as far as I am concerned this forum is not a pi&&ing contest its for electricians to help each other out and yes there is some old heads like me are big on safety so when advice is given the person asking it needs to realise the they are tapping into a wealth of knowledge yes I know that sometimes advice can sound condisending but remember this is not a game people can and do die with house electrics and over the years every apprentice I have had I have said "do you trust me when I tell you its isolated ?" and when I get the "O yes" reply I tell them wrong answer I add you are your own safety man so the answer I want to hear is "well fine but I will still be checking it" and far from being insulted when they question me I am pleased hence why I am still alive today

So do not take it the wrong way if you are questioned about how you are doing something because its not a personal attack but more of a concerned individual wanting to make sure things are done correctly remember we get posts on this forum daily from people who may want to cut corners or have a pretty neat idea how to do something and sometimes they will say "But why not" and thats fine but at the end of the day we are not reinventing the wheel

 

[Ohmyword]

Just to sober everyone up here in Glasgow today a Sherif found a "handyman" at fault for the death of a 21 month old toddler after the child put a "disconnected" oven supply cable in his mouth so heres the deal as far as I am concerned this forum is not a pi&&ing contest its for electricians to help each other out and yes there is some old heads like me are big on safety so when advice is given the person asking it needs to realise the they are tapping into a wealth of knowledge yes I know that sometimes advice can sound condisending but remember this is not a game people can and do die with house electrics and over the years every apprentice I have had I have said "do you trust me when I tell you its isolated ?" and when I get the "O yes" reply I tell them wrong answer I add you are your own safety man so the answer I want to hear is "well fine but I will still be checking it" and far from being insulted when they question me I am pleased hence why I am still alive today

So do not take it the wrong way if you are questioned about how you are doing something because its not a personal attack but more of a concerned individual wanting to make sure things are done correctly remember we get posts on this forum daily from people who may want to cut corners or have a pretty neat idea how to do something and sometimes they will say "But why not" and thats fine but at the end of the day we are not reinventing the wheel

A man after my own heart!
I tend to follow the quote of "wrong answer" with a clip round the earole just to make it certain that the message has sunk in ;-)
They can't (and mustn't) rely on ANYBODY in our trade. They MUST learn to take responsibility for their own safety in this game.

 

[impecc]

Sorry if this has been answered before. If changing a CU with 100A double pole isolator, are you saying that is not composory to compel the DNO to change the tail to 25mm2 and supply earth to 16mm2?

 

[truckster]

Sorry if this has been answered before. If changing a CU with 100A double pole isolator, are you saying that is not composory to compel the DNO to change the tail to 25mm2 and supply earth to 16mm2?

The size of the isolator is not the determining factor but the size of the fuse in the cut-out. Nominally these are 100A whilst in reality they are more likely to be 80A or even 60A. The 25mm tails debate has been stirred by the OSG stating tails should match the nominal rating. The DNO's are usually happy with 16mm as they know they will only supply an 80A fuse.If you are concerned about it you need to get a definite answer from the DNO in question.

The tails and earthing conductor are the customers/your responsibility, the DNO's won't change them.

 

[pete433]

Hi

The correct procedure should be as follows:

1 - Periodic inspection & test
2 - Remedials works repaired
3 - Fuse board can then be changed as the house will be to regs
4 - Final testing and electrical installation certificate issued.

 

[malcolmsanford]

Hi

The correct procedure should be as follows:

1 - Periodic inspection & test
2 - Remedials works repaired
3 - Fuse board can then be changed as the house will be to regs
4 - Final testing and electrical installation certificate issued.

Welcome to the forum but though a good practice not every client will pay for a PIR, and certainly on a CU change only what remedials would you expect?

What if the house installation does not have a lighting CPC, This would contravene regulation 412.2.3.2, so would you not continue with the CU change.

 

[pete433]

When a conumer unit is replaced the electrical contractor is responsible for all circuits that are distributed from it, if a lighting circuit has no CPC with class I fittings then the consumer unit should not be replaced as you are leaving the installation in a dangerous condition, unless you are willing to replace all fittings to class II and note on the fuseboard and certificate there is no earth you should not go ahead. If a periodic is undertaken first, all issues will be found, this is a transparent way of working for you and the customer.

Remember that this is standard practice, also remember that you cannot issue an electrical installation certificate with faults applied to it.

 

[nikmet]

pete, what sort of average price are you ending up at after carrying out a cu change, pir and repairs to 'standard practice' and how many hours on average do you spend without taking any faults into account?

 

[pete433]

The regulations are there to be adhered to, I have found over the years that if you give customers the right information and inform them of the correct format for a consumer unit change probably over 90% will apreciate the information and we will gain the contract. Some installs after the PIR can be a few hours work others a few days for remedial, are main concern is that the property is to regulations and that the installation certificate will hold up to regulations. The days of just slapping a consumer unit in are long gone and rightfully so. All of the relevant bodies will back-up the pir,remedial,ccu change, test procedure.

 

[nikmet]

The regulations are there to be adhered to, I have found over the years that if you give customers the right information and inform them of the correct format for a consumer unit change probably over 90% will apreciate the information and we will gain the contract. Some installs after the PIR can be a few hours work others a few days for remedial, are main concern is that the property is to regulations and that the installation certificate will hold up to regulations. The days of just slapping a consumer unit in are long gone and rightfully so. All of the relevant bodies will back-up the pir,remedial,ccu change, test procedure.

I agree 100% with what you are saying, i was just genuinely interested as to how many hours for, pir, cu change, final testing, completing certificates, I am constantly hearing of sparks doing cu change in 4hours complete, (2 a day) and I think this is impossible to do it correctly in 4 hours?

 

[pete433]

The Pir will vary but we would look at around a day to complete the inspection with the paperwork (easycert). After PIR we will explain the issues found and produce an estimate for repair.

The consumer unit change will take around a day this includes overall install and testing.

I agree I heard of a sparks who undertook four inspection and tests in a day including completion of paperwork, he must of run around and missed a lot!!!!

 

[malcolmsanford]

You still have not really answered my question concerning 412.2.3.2. Yes you are correct that no class I type of equipment should be use, but the reg clearly states that a CPC must be at every point of the circuit that supplies one or more Class II items of equipment.

Your opening statement that by doing your PIR and remedials, which will leave the installation conforming to the regs is perhaps not quite correct, unless for every non CPC lighting circuit you encounter you advise the client that it must be re-wired to conform to the current regulations, which IMO is a money making scheme, as the regulation are not retrospective.

I would be most miffed if you changed my CU change and then extraed me for fitting over sleeving on switch lines, over sleeving on bare CPCs, as you picked that up on your PIR and as it now fails the current Regs it should be redressed.

A PIR is not done to ensure that the existing installation is to the current regs, it is done to ascertain the conditgion and continuing use of the installation.

 

[pete433]

As per your last comment about the PIR the penny has hopefully dropped, you test the installation to ascertain the condition of the property, you then are required to bring the property up to BS7671 before a consumer unit is installed, then on completion an eletrical installation certificate is issued. There are a few caviates as explained in the ECA with regards to CPC and lighting, we as a company will not replace a fuse board if any circuits are missing an earth. Also it is good practice to check all connections and denotation of switch wires can be undertaken whilst doing this, good luck.

If you as a company choose to install a CU without an earth to lights the below reg in extreme circumstances can be used

Regulation 412.1.3, where, under the strict conditions imposed by that regulation, Class II or equivalent insulation is used as the sole means of protection against indirect contact for a whole installation or circuit.

 

[malcolmsanford]

So you do not as a whole change a CU unless the lighting circuit is upgraded to have a CPC?

Your work as to conform to BS 7671-2008 and your work is a CU change, not the existing installation. How do you know even after an a thorough PIR that there is not an un-accessible junction box under the floor or even buried in a wall? Are you going to start to dismantle everything to ensure before you change that CU the installation is now compliant in every detail.

So if an entire house on your CU change did not have sleeving you are quite prepared FOC to undo every connection to every appliance that required sleeving?

Your CU change is just that a CU change unless every customer you deal with is totally prepared to pay for perhaps 2-3 days labour cost, for bringing the existing installation upto the current standards, then your remit is to ensure that the alteration to the installation will not adversly effect it, I would be interested to see you post the relevant Regs that insist that an existing installation as to be upgraded to the existing BS standard before any alteration or addition can be done.

 

[Chr!s]

Pete 433

Please try link :http://www.esc.org.uk/industry/industry-guidance/best-practice-guides/

Read Guide 1 and 6 these may help.

Regards Chris