y oh y

[cliffed]

taking over a job from a old sparkie,really nice jobby,trunkin & conduit,biggest warehouse.Wots your feelin on this,cos just had a mighty row wiv him.3 lighting circuits cabled in 2.5mm,quite a long run,switching low bay lighting in 3 rows,via 2 2way switches & 1 intermeddiate.At the switch position there shud of been 3 earths to match the 3 circuits,but no,the earths stop at the lighting points,& 1 earth is then taken from a circuit 2 the switch,this happens at all switch positions,so wot do u think.Major problem now is gettin the relevant earths 2 each switch,cos 25mm conduit full 2 the brim,my gaffer thinks it may b ok,but he wud.

 

[malcolmsanford]

To be honest Si it seems to be an overall dumbing down of the industry. The same way lecturers seem to think that using the armour of a SWA is no longer acceptable as a CPC, and the very mention of the word MICC brings them out in a cold sweat.

I guess the industry as evolved, there is less time to do things, and so I guess things like properly designed installations and installations designed to their environment is a thing of the past.

It is so much easier to teach/train someone for SWA use a 3/5 core and the extra core as the CPC, metal containment draw in a separate conductor for the CPC and MICC well easier to use XYZ cable than MICC.

It just means that training is easier for lecturers and colleges, and the industry instead of getting fully trained electricians are getting a generation of guys who "have been trained" as such.

Perhaps I'am a dinosaur, after all why go to the problem of working out if a SWA armour or piece of conduit can be utilized as a CPC, when it's so much easier to use a 3rd core or pull in a separate conductor. I just know in my mind, being taught how to do this I think made me a better sparks, as it gave me more options to work with, and gave me a greater insight into why things were done, it made me think for myself, something I think the modern lecturers are trying to eliminate from our industry

 

[SPARTYKUS]

And besides, it's perfectly acceptable to use the armour or continuous conduit as the cpc (should it step up to the sizing).

Still in the regs.

 

[Engineer54]

Interesting...

I thought that was old hat now and could no longer be relied upon, hence why people are now using separate wires for the CPC...

At least, that's what my lecturers told me.

Then yet again we have a lecturer that hasn't got a clue!! And i guess why we get so many newbies here that don't understand the difference between main earthing, bonding, and circuit CPC's etc....

 

[Mr.Si]

To be honest Si it seems to be an overall dumbing down of the industry. The same way lecturers seem to think that using the armour of a SWA is no longer acceptable as a CPC, and the very mention of the word MICC brings them out in a cold sweat.

I guess the industry as evolved, there is less time to do things, and so I guess things like properly designed installations and installations designed to their environment is a thing of the past.

It is so much easier to teach/train someone for SWA use a 3/5 core and the extra core as the CPC, metal containment draw in a separate conductor for the CPC and MICC well easier to use XYZ cable than MICC.

It just means that training is easier for lecturers and colleges, and the industry instead of getting fully trained electricians are getting a generation of guys who "have been trained" as such.

Perhaps I'am a dinosaur, after all why go to the problem of working out if a SWA armour or piece of conduit can be utilized as a CPC, when it's so much easier to use a 3rd core or pull in a separate conductor. I just know in my mind, being taught how to do this I think made me a better sparks, as it gave me more options to work with, and gave me a greater insight into why things were done, it made me think for myself, something I think the modern lecturers are trying to eliminate from our industry

You know what, I'd sooner accept the thoughts and practises of you guys on here than those of my lecturers! (I only rate one as being useful) I see no problem with a continuous metal conduit or other containment being used as the CPC.

I wish I had had more time on MICC. We only got part of one day to "Learn" how to make it off, so if I was ever to take a job wiring up a petrol station for example, I'd be useless! (still looking for someone to take me under their wing in the big wide world so I can get my NVQ3 / 2356). Then, hopefully, the learning can happen!

 

[Engineer54]

ok but there are 3 circuits at the switch position,all at 16 amps,would you still be ok about 1 earth at switch,instead of 3,it is galv conduit & trunking,its wired in singles.Sorry about my english,im half welsh u no.

As pointed out before, there is NO NEED for any separate CPC's to be run-in metallic conduit/trunking installations, the containment IS the CPC!! So in essence both you and the old timer are wrong!! Although there is no harm done running a separate CPC, it SHOULDN'T be necessary and certainly not necessary to pull-in a CPC for each circuit as your suggesting....

 

[oldtimer]

Malcolm I agree with what you are saying I am from the 14th edition and you have read this before "Electrically and Mechanically sound" now what that means is you can and did use the swa or the conduit as an earth and I even asked a technical question on another forum where schemies answer and the logic was how can I change a DB in a flat where the light circuits in a conduit that is Electrically and Mechanically sound but I cannot get access to add a cpc in the flat upstairs and the reply was yes as long as you get the correct Zs then ok where 6 months before it was sorry you need to run a cpc.

And as for our trade being devalued well I have said it before we allowed the schemies to run roit and issue registrations to everyone and their dog and as for qualifications well as long as they ticked the boxes and could pay their subs then it was ok mind you the differance between an old hoar and a schemie is that the old hoar IS fussy who jumps into bed with her.

Yes we older guys stick to our guns and sometimes it can cost us as 5 week Willie is happy to do it for less than the guy stacking beans in my local Tesco and yes it can get frustrating hence why we can blow some steam off on this forum. So do i dispair of our trade well yes we now being undermined by a minority that is hell bent on looking after itself instead of maintaining standards and for you young guys out there who are doing cheap jobs that work out to £7 an hour remember the guy who is stacking beans in Tesco is on the same money and gets paid holiday sick leave a bonus plus he gets to buy cheap shares so ask yourself this who,s the daft one here then

 

[malcolmsanford]

Then yet again we have a lecturer that hasn't got a clue!! And i guess why we get so many newbies here that don't understand the difference between main earthing, bonding, and circuit CPC's etc....

That Col is spot on, the reason we are getting sparks into the trade that have no idea what the difference between bonding and earthing, is due IMO to this gap in their training concerning this.

When I was asked to test the continuity of trunking/conduit or to work out if an armour was sufficient as a protective conductor, long before CPC was in vogue, it taught me WHY we did things and what it meant, now we are just training guys to "do it this way"................

 

[cliffed]

ok wot if the containment changed to plastic conduit,wud u still run 1 earth for 3 circuits,

 

[malcolmsanford]

Has it been changed to PVC?

If the integrity of the conduit as been breeched, then you need to address that, and that could be done by either running a CPC for each circuit, or a bridge to reform the integrity.

As a bridge would IMO be too much faffing about then yes you should run a separate CPC for each circuit, as per regulation 412.2.3.2

 

[Knobhead]

Why would you change to PVC?

 

[Guitarist]

Why would you change to PVC?

I think cliffed is just trying to get his head around the sizing issue (correct me if I'm wrong cliffed), ie the need for 3 seperate small cpc or 1 big cpc to replace the conduit/trunking.
If I have misunderstood then please forgive me.

 

[GLENNSPARK]

To be honest Si it seems to be an overall dumbing down of the industry. The same way lecturers seem to think that using the armour of a SWA is no longer acceptable as a CPC, and the very mention of the word MICC brings them out in a cold sweat.

I guess the industry as evolved, there is less time to do things, and so I guess things like properly designed installations and installations designed to their environment is a thing of the past.

It is so much easier to teach/train someone for SWA use a 3/5 core and the extra core as the CPC, metal containment draw in a separate conductor for the CPC and MICC well easier to use XYZ cable than MICC.

It just means that training is easier for lecturers and colleges, and the industry instead of getting fully trained electricians are getting a generation of guys who "have been trained" as such.

Perhaps I'am a dinosaur, after all why go to the problem of working out if a SWA armour or piece of conduit can be utilized as a CPC, when it's so much easier to use a 3rd core or pull in a separate conductor. I just know in my mind, being taught how to do this I think made me a better sparks, as it gave me more options to work with, and gave me a greater insight into why things were done, it made me think for myself, something I think the modern lecturers are trying to eliminate from our industry

maybe the powers that be see those that can think on their feet as dangerous malc.....so better to stamp out such notions quick...before it takes hold......

 

[GLENNSPARK]

I think cliffed is just trying to get his head around the sizing issue (correct me if I'm wrong cliffed), ie the need for 3 seperate small cpc or 1 big cpc to replace the conduit/trunking.
If I have misunderstood then please forgive me.

well its a minimum of 2.5mm CPC anyway ...as its metal conduit....

 

[cliffed]

I think cliffed is just trying to get his head around the sizing issue (correct me if I'm wrong cliffed), ie the need for 3 seperate small cpc or 1 big cpc to replace the conduit/trunking.
If I have misunderstood then please forgive me.

basically their r 3 circuits of lighting,switched via 2 way & intermeddiate switching,the issue relates 2 the switch positions only,instead of continuing the earths 2 each switch,there is only 1 earth at each switch position,wud this b ok thanks.

 

[Brightspark2]

basically their r 3 circuits of lighting,switched via 2 way & intermeddiate switching,the issue relates 2 the switch positions only,instead of continuing the earths 2 each switch,there is only 1 earth at each switch position,wud this b ok thanks.

Yes!...