The Scotland England difference

[scotsparky]

I known this may start a debate however its a good question.

I have just had a look at Mr Marks Sparks install in the "Show us your installs " tread and notice a difference. When i served my time in Scotland we had to put a lockring at every coupling,conduit joint. However i noticed mr MarkSparks had none on his conduit. Is this an English thing and if so why??

 

[captainconduit]

in scotland lockrings are on 99% of installs but i think are a waste of time as long as coupling is tight. The job im on now is using conduit boxes with a allen key grub screw to tighten onto the conduit,even couplings with grub screw no threading,so good. But saying this above ceilings and stud walls ok but not surface conduit but got 110v threading machine even better.

 

[Darkwood]

Served my timed as apprentice here in yorkshire 1990 and we were taught to use lockrings as it reduces the risk of loosening from vibration etc especially as its can be used as an earth.

 

[scotsparky]

captain the use of a grubscrew? isnt that the same as the old split pin ? If so i am assuming it cant be uses as an earth and an earth connection has to be at every joint?

 

[zupos40]

Only time I put locknut (milled edge or hexagen) was on runners, otherwise lenght joined by coupler with each lenght with half coupler thread on to them, 3 threads past the dies.

 

[ashrow]

I got told that when the conduit was not the earth for the circuit/various circuits then no lock ring required but i must admit it did guarantee a good and proper connection and still use it today (make me feel better!!!!)
I have only been a spark since 1988 and still cant understand that we used conduit/trunking/swa sheath as a earth, give me a cpc per circuit and i can be sure (sleep well at night) its right.

ASH

 

[captainconduit]

suarface conduit lockrings purely for aesthetic reasons not waste time if pipe is hidden. Scotspark, every joint has a grub scew but cpc cable used for eathing purposes, dont bother with serated washers, also on market is conlock conduit accessories same idea as grub srew but push on n.ot that good though

 

[ecclescake]

Lockrings or locknuts on runners only that's how i got taught.

 

[captainconduit]

no need for runners with push on or conlock coupling

 

[ecclescake]

no need for runners with push on or conlock coupling

I'll sleep better now

 

[scotsparky]

suarface conduit lockrings purely for aesthetic reasons not waste time if pipe is hidden. Scotspark, every joint has a grub scew but cpc cable used for eathing purposes, dont bother with serated washers, also on market is conlock conduit accessories same idea as grub srew but push on n.ot that good though

even though CPC used for earthing how do you garentee the earth path using gub screw in the event of an Fault to the metal conduit.

 

[captainconduit]

you cant, the install is only as good as you've left it, tested thoroughly can sleep at night. Never going to be as good as threading but continuity is still achieved in normal conditions,suppose this product wouldnt be mass manufactured if not effective

 

[scotsparky]

There a lot produced thats not effective its up to the tradesman to decide what to use. Rember its you going up in fron of the judge if its wrong.

 

[captainconduit]

thats true but i dont sign the test sheets lol

 

[ryanryan]

conduit/trunking/swa sheath as a earth, give me a cpc per circuit and i can be sure (sleep well at night) its right.

ASH

All these parrellel paths will only help with your Zs.

 

[benji]

Basically its the company you work for who decides what type of installation/materials that are used ,but if the test results don,t add up you,ll be putting an extra cpc in

yours benji

 

[captainconduit]

yes i work for a company but i order the materials and installation is designed by electrical designers who always air on the side of caution by uprating cpc size. Some people are not up for change and again test results are all within max values.

 

[scotsparky]

have you ever tested the conduit continuity captain?

 

[captainconduit]

Tested containment at various points of install and all results were under 1 ohm so ok . RCBO s installed on ring mains and many parrallel earths so all good. Containment i suppose is primarily for mechanical protection. scotty

 

[Mac]

When i did my apprenticeship in the 80's,i was taught that lockrings/locknuts were only used on runners and all the joints were painted with galvanised paint.

 

[scotsparky]

Tested containment at various points of install and all results were under 1 ohm so ok . RCBO s installed on ring mains and many parrallel earths so all good. Containment i suppose is primarily for mechanical protection. scotty

you suppose?? interesting answer On old PME systems the conduit /trunking was the earth a lot of those installations dont have RCDs so its vital you have a decent earth throught the metalwork, under 1 ohn isnt a very good reading there is it capain? it has to be a lo under near 0.05 ohms.

Dont rely on rcds as a get out for bad installs and desighn they are SUPPLIMENTARY fault protection.

 

[captainconduit]

food for thought scotspark