what tests are you doing on consumer unit change.

[jumpin jax]

For domestic i think a real time saver is to get a R2 lead, this also allows quick cpc testing at every point. Just make sure there are no painters or plasterers on site or the lead won't last too long!

 

[Engineer54]

Well, RCD's are installed nowadays so no need to do insulation resistance test, cos yer RCD won't set if there's a problem. Then a couple of Zs tests here and there to make sure you've got an earth.

The rest of the testing is carried out at home. :behead:

You should always be conducting tests ''Prior'' to any CU change!!

Errr, ... there are normally no RCD's in the CU ''Before'' changing the CU, ....But there is AFTER!! ...IR testing is essential, Pre a CU change. You may not be able to get either RCD to hold in after your CU change if the insulation levels are too low!!!

Even after a CU change, and even if the RCDs are holding in, IR testing should be carried out as a matter of course, it's a record against which any future EICR can be compared. Which in essence, is one of the fundamental reasons of EICR's in the first place, ...monitoring any deterioration of the installation!!....

 

[Sparky Ninja]

This is the ESC advise
10.2. In addition, as a minimum, the following testsshould be carried out to the existing circuits
connected to the replacement consumer unit.
• A continuity test of the protective conductor of
each circuit, to the point or accessory electrically
furthest from the consumer unit and to each
accessible exposed-conductive-part.
• A continuity test of all ring final circuit
conductors.


Note
R1+R2 values are not mentioned
Here is a link if you want to refer to their bumph
http://www.esc.org.uk/fileadmin/user_upload/documents/industry/best_practice/BPG6_09.pdf

Naturally R1&R2 or R2 would be required for the first test mentioned.

 

[roukel01]

You should always be conducting tests ''Prior'' to any CU change!!

Errr, ... there are normally no RCD's in the CU ''Before'' changing the CU, ....But there is AFTER!! ...IR testing is essential, Pre a CU change. You may not be able to get either RCD to hold in after your CU change if the insulation levels are too low!!!

Even after a CU change, and even if the RCDs are holding in, IR testing should be carried out as a matter of course, it's a record against which any future EICR can be compared. Which in essence, is one of the fundamental reasons of EICR's in the first place, ...monitoring any deterioration of the installation!!....

Sorry, I thought that by putting the little picture on the end, you would realise it was ment as a joke.

 

[Engineer54]

Sorry, I thought that by putting the little picture on the end, you would realise it was ment as a joke.

Sorry, .....Probably just me not noticing..lol!! Been busy reviewing drawings and writing them up tonight!!
So only popping on here in between and coffee/smoke breaks...lol!!

Time for bed now i think, my eye's are tired...:yawn: lol!!!

 

[Des 56]

Naturally R1&R2 or R2 would be required for the first test mentioned.

Naturally and agreed,its one or the other required


The listed test procedure was in response to the first post

quote
i normally do the R1+R2 tests as well but takes extra time and is it really nessesary

The test procedure was pasted and the required Zs test was highlighted
I included a note that R1+R2 values were not mentioned with regard that question
Des

 

[Deleted member 9648]

You should always be conducting tests ''Prior'' to any CU change!!

Errr, ... there are normally no RCD's in the CU ''Before'' changing the CU, ....But there is AFTER!! ...IR testing is essential, Pre a CU change. You may not be able to get either RCD to hold in after your CU change if the insulation levels are too low!!!

Even after a CU change, and even if the RCDs are holding in, IR testing should be carried out as a matter of course, it's a record against which any future EICR can be compared. Which in essence, is one of the fundamental reasons of EICR's in the first place, ...monitoring any deterioration of the installation!!....

The 'real world' problem with tests prior to a CU change is more often than not you are asked to quote for the job. So you go round and carry out a full set of tests which takes time...and then dont get the job....sod that.
When we quote for a CU change a visual inspection is usually sufficient to get a feel for the likelyhood of any issues,and our quote clearly states that any problems encountered during the CU change may incur extra cost. Testing and inspection is then carried out at the time of the change. I am an experienced fault finder and cant recall any issue which added more than a couple of hours to a job. I've done hundreds of cu changes and there have never been any customer problems with this approach.
This might not be a text book approach,but there are no ideal solutions here....a text book approach is liable to result in me carrying out a pir for nothing....and I aint doing that.
Those who cant trace faults may prefer not to adopt this way of doing things.

 

[ezzzekiel]

i agree with him above :iagree:

 

[roukel01]

Same here, its how I've always done it.

 

[Engineer54]

The 'real world' problem with tests prior to a CU change is more often than not you are asked to quote for the job. So you go round and carry out a full set of tests which takes time...and then dont get the job....sod that.
When we quote for a CU change a visual inspection is usually sufficient to get a feel for the likelyhood of any issues,and our quote clearly states that any problems encountered during the CU change may incur extra cost. Testing and inspection is then carried out at the time of the change. I am an experienced fault finder and cant recall any issue which added more than a couple of hours to a job. I've done hundreds of cu changes and there have never been any customer problems with this approach.
This might not be a text book approach,but there are no ideal solutions here....a text book approach is liable to result in me carrying out a pir for nothing....and I aint doing that.
Those who cant trace faults may prefer not to adopt this way of doing things.

I think you hit the nail on the head with your last sentence!! lol!! Far too many new electricians out there these days, that are not skilled at fault finding!! Having said that, how long does it take to do a few IR tests, and a quick check for the borrowed neutral syndrome?? I think i'd do these brief tests, just so i'd know where i stand, and what i was in for after the new CU has been installed!!

 

[daz1963]

Thanks to all who responded.

 

[Tuttle]

Personally I don't do a Zs measurement on radial circuits if I can help it. I use Ze+(R1+R2). Particularly on lighting circuits I don't like removing roses etc to get to the earth when the cct is live.

That's what I used to do, in fact that's what I was taught to do, but the chap from ELECSA was not impressed. He said that I had to open up the ceiling rose, do a live Zs measurement and record that on the EIC, not just calculate from the Ze and R1+R2 measurements. Don't know if that was his own personal opinion or the opinion of ELECSA though. I think that he was concerned about the possiblity of the CPC being disconnected from the CU while performing the R1+R2 test and then not getting reconnected properly.

 

[brman]

I was also taught Ze+(R1+R2) is the preferred method as reduces live working and so conforms to EWR 1989. On the other hand I was chatting to my tutor when doing my 2395 practical last night and he agreed that a Zs on the cct was a good idea to ensure you have put everything back together properly. However he was quite happy I didn't do it during my practical as it isn't required by guide note 3.

I have to admit that, after reading this thread and thinking about it a bit more, I will probably do a Zs on radials in the future as long as I can find a safely accessible ceiling rose or whatever. I am not going to lose sleep if I don't though!

btw. Who was the elecsa chap? I have David Turpin turning up tomorrow to do my assessment.

 

[rich.250]

EIC!
As its a new install effecting every cct from that DB.

 

[Tuttle]

Who was the elecsa chap? I have David Turpin turning up tomorrow to do my assessment.

I can't remember his name, but I'm pretty sure it wasn't David Turpin