Fly Leads For Swa On A Metal Clad Db

[Industspark]

Once again after some knowledge from some wise old men.
As per photo, I have been issued from a contractor a C2 for 'The MICC/SWA or earth bar cables earth system is incorrectly connected.'
I have 26 metal clad consumer units with this C2 where the earth tag has been fitted with nut & bolt. However, because there's not fly lead going to the earth bar as the top of DB can be removed using tools,they've not specified a regulation but say it's incorrectly fitted.
Others include the earth stud not being connected, which I believe is there for bonding not to connect main earth to.

My question is, If its a metal clad DB are fly leads required( what reg) if the lid is designed with removable top surface with use of a tool.( nut & bolted)?
Many of the installations were constructed to BS 7671 15th & 16th edition.

 

[Leesparkykent]

Is the armour being used as the CPC?

 

[westward10]

You could try Reg 543.2.7.
Regulations 8 and 10 of EAWR also make reference to ensure connections are capable of carrying fault current and how to make these connections.

 

[DPG]

Could you clarify - are the glands fitted to a removable gland plate? Daz

 

[westward10]

Is the armour being used as the CPC?

Does this matter, if the armour has the potential to carry fault current then the connection should be of the same integrity whether it is used as a cpc or not.

 

[Leesparkykent]

Does this matter, if the armour has the potential to carry fault current then the connection should be of the same integrity whether it is used as a cpc or not.

Yes obviously it matters if its used as the protective conductor........If DB is compliant/type tested to BS61439 then it could well be compliant and not warrant a code 2.

 

[westward10]

Not debating the Code 2. It is not relevant whether it is the cpc or not, the armour has the potential to carry fault current.

 

[Leesparkykent]

Not debating the Code 2. It is not relevant whether it is the cpc or not, the armour has the potential to carry fault current.

I never said it didn't either...........

 

[westward10]

I never said it didn't either...........

Okay point taken, either way the integrity of the connection must be maintained and the best way to do it is to fit a cpc to the earth washer.

 

[Leesparkykent]

Okay point taken, either way the integrity of the connection must be maintained and the best way to do it is to fit a cpc to the earth washer.

not doubting that.

 

[Industspark]

I understand has to be sufficiently earth, my point is that all parts of the installation that can become live under fault current have to be earthed. This means that the Db itself being metalclad has been designed for this, so these older systems have been glanded onto the Db with earth tags bolted,just no flyleads onto the earth bar itself.
Yes the lid is removable with use of a tool.
I'm quite happy to go round and flylead 26 industrial DB's which will need to be isolated causing loss of production. however, I don't want to be doing so if while the earth continuity is satisfactory.

 

[LankyWill]

We had the same issue the other week, came up as remedial's on a eicr, i said its a metal clad db that has an earth path due to the construction of the Board(metal) but my QS was being an arse. To save time fit piranha nuts with fly lead already prepped. He said unless the paints been scrapped off i had to fly lead.

 

[Industspark]

We had the same issue the other week, came up as remedial's on a eicr, i said its a metal clad db that has an earth path due to the construction of the Board(metal) but my QS was being an arse. To save time fit piranha nuts with fly lead already prepped. He said unless the paints been scrapped off i had to fly lead.

If a lot of them weren't 15-20 years old I'd understand. yet they've been tested and never been a issue. These guys have even marked up no evidence of RCD testing or ACB testing even though there's 5 years of reports.
I'd go ahead and just crack on but the cost from loss of production alone will be tens of thousands of pounds.

 

[sam400]

Reg 543.2.2 i) is applicable here, but it's open to interpretation.
Personally I think it's bad practice to rely on the self tappers holding the gland plate on for continuity, I would like to see a bond from the earth bar to the plate.

We wouldn't worry about earth tags and fly leads if we were terminating a metal conduit?

 

[Industspark]

Reg 543.2.2 i) is applicable here, but it's open to interpretation.
Personally I think it's bad practice to rely on the self tappers holding the gland plate on for continuity, I would like to see a bond from the earth bar to the plate.

We wouldn't worry about earth tags and fly leads if we were terminating a metal conduit?

They are x4 machine screw's not tappers, and not conduit but have been glandes with fly leads into metal clad sockets. This is why I wanted a regulation explaining why fly leads are required.
If they said C3 for improvement recommended but C2 for so many DB's giving a unsatisfactory report on each is creating un-necessary work.

 

[Industspark]

I'd say 543.2.6 allows the consumer unit metal clad surface to be used. Painted surface isn't a issue as earth tag (banjo) has been nut & bolted.

 

[Lucien Nunes]

Banjo bolt will only make good connection if paint has been stripped, otherwise it will be no better than the gland nut. Is there a gasket under the gland plate?
The regs aren't so prescriptive as to say a fly lead is or isn't required, it's a matter of whether the particular piece of work in front of you makes a sound connection. The devil is in the detail and we can't see that from here. I never rely on steel fixing screws alone, I would always fit a nickel-plated brass bolt lock-nutted through the banjo etc or use a Piranha but that is my personal preference. Clean BZP steel screws tightly fastened through a gland plate in a low-corrosion enviroment can make a decent connection.

 

[Deleted member 26818]

Has the earth continuity on these cables been checked?
The requirement is just to earth, not to use a particular method.
If ther is earth continuity and the Zs is low enough to allow the OCPD to operate, I cannot see a problem.
However best practice would to my mind be to have used a fly lead, just the same as with metal back boxes.
To my mind, unless there is no, or poor earth continuity, there is no call for a code C2.

 

[Industspark]

The continuity has been checked and very low.And yes it may be best practice to fit flyleads but most these DB's were fitted over decade ago some 20 years.
Banjo has been fitted, drilled and bolted.
My issue is I have to go to site manager and he's not going to accept its just against regulation, he will require a actual regulation number and why its a C2 after 20 years of being ok.
He's an engineering manager and quite a intelligent chap. To shut down a 24 hour site to do the repairs when should be a C3 at most I'd like to either send report back saying it's within regulation or to go in knowing It's the right thing to do.

 

[Industspark]