reg 132.16 - how flexible is it? :)

[brman]

Ok, before I start I should say that I normally assume that 132.16 means that bonding and earthing should be ok before ANY additions or alterations take place. However I just wanted to explore what the reg actually means.

So....
"no addition or alteration.... shall be made... unless it has been ascertained that the rating and the conditionn of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate"

As I read this that means you are only concerned whether the earthing and bonding is ok for the addition, not the whole system.
So, lets take an example: Adding a socket spur to a ring at an existing socket where the Zs is say 0.8. Lets also say the Zs at the origin is 0.2.

Using those figures I get a PEFC for the installation of 1.15kA (ie. 230/0.2) and a PEFC at the modification of 287A (230/0.8).
So, assuming a 100A BS88-2 main fuse with a 1.15kA PEFC I get t = 0.4s ish and the adiabatic gives me main earthing conductor CSA = 6.3mm2 to protect the whole system.

However if I am only concerned about the addition then my PEFC is 287A through a 32A type B MCB giving me a CSA= 0.8mm2!!

So, leaving aside arguments about common sense and making sure the whole system is safe, if the customer refuses a earthing upgrade am I allowed to make this alteration and sign it off if say there is a 4mm2 earthing conductor present? Obviously with a note that there is a C2 fault on the cert!

This goes against what I thought was allowed so I am very interested to hear other views and why.....

 

[spark 68]

The part where it says 'shall be adequate for the protective measure applied' is the other important part, ie. for where ADS is used

 

[brman]

The part where it says 'shall be adequate for the protective measure applied' is the other important part, ie. for where ADS is used

I agree ADS must be achieved but surely that would still be covered with an reduced CSA main earthing conductor as long as the Zs was ok. (which it is in my example)

 

[spark 68]

I mentioned ADS as it was previously called EEBADS, and as the reg says 'shall be adequate for the protective measure applied' , I took this to mean every circuit or addition that relies on this protective measure, taken in conjunction with the opening paragraph it seems pretty clear, ie. Shall

 

[Top Cat]

Ok, before I start I should say that I normally assume that 132.16 means that bonding and earthing should be ok before ANY additions or alterations take place. However I just wanted to explore what the reg actually means.

So....
"no addition or alteration.... shall be made... unless it has been ascertained that the rating and the conditionn of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate"

As I read this that means you are only concerned whether the earthing and bonding is ok for the addition, not the whole system.
So, lets take an example: Adding a socket spur to a ring at an existing socket where the Zs is say 0.8. Lets also say the Zs at the origin is 0.2.

Using those figures I get a PEFC for the installation of 1.15kA (ie. 230/0.2) and a PEFC at the modification of 287A (230/0.8).
So, assuming a 100A BS88-2 main fuse with a 1.15kA PEFC I get t = 0.4s ish and the adiabatic gives me main earthing conductor CSA = 6.3mm2 to protect the whole system.

However if I am only concerned about the addition then my PEFC is 287A through a 32A type B MCB giving me a CSA= 0.8mm2!!

So, leaving aside arguments about common sense and making sure the whole system is safe, if the customer refuses a earthing upgrade am I allowed to make this alteration and sign it off if say there is a 4mm2 earthing conductor present? Obviously with a note that there is a C2 fault on the cert!

This goes against what I thought was allowed so I am very interested to hear other views and why.....

What a great question, going to have to think about that!

 

[StuSpiers]

if the customer refuses a earthing upgrade

dangerous condition notice and walk.

no bonding - no bounce.

That is what I would do others may say different.

 

[brman]

I mentioned ADS as it was previously called EEBADS, and as the reg says 'shall be adequate for the protective measure applied' , I took this to mean every circuit or addition that relies on this protective measure, taken in conjunction with the opening paragraph it seems pretty clear, ie. Shall

But an undersized main earth would be adequate for the protective measure applied for the safety of the addition or alteration.... just not for the whole system.

 

[spark 68]

It is an interesting question.

However I refer to this part: "no addition or alteration.... shall be made... unless it has been ascertained that the rating and the conditionn of any existing equipment..."

 

[brman]

dangerous condition notice and walk.

no bonding - no bounce.

That is what I would do others may say different. [/COLOR]

Ok, that I didn't expect purely because I only give dangerous condition notices for C1 faults. Dodgy earthing or bonding is a C2 I believe. But ignoring that I can see why you would walk as that was my view before I started thinking about it too hard :lol:

 

[StuSpiers]

Yhea I guess your right about c2

But some customers do need a proverbial slap round the face - and the dangerous condition does that.

Technically incorrect but if it gets a safer install for them and more importantly covers your ---.......

When you start bending fairly clear regulations to fit customers whims that's when to take a step back.

Of course it's only my opinion.

 

[Guitarist]

I think that regardless of what they think, if a customer starts arguing with your professional opinion regarding a matter of safety (earthing), then definitely walk. I bet they wouldn't argue with the salesman, when ordering a car, about whether to have a seatbelt fitted just because they don't think it is necessary.

 

[brman]

It is an interesting question.

However I refer to this part: "no addition or alteration.... shall be made... unless it has been ascertained that the rating and the conditionn of any existing equipment..."

yes, a very good point. But then I would argue that that is intended to ensure that existing protective devices and and cables on the affected circuit would be adequate for the addition. ie. cable size ok for the load, PD trip in required time etc. But only for the alteration.
So as long as the cable or PD is ok for the new socket I don't have to worry about whether someone has put a shower on the circuit and overloaded it elsewhere.
Taking that arguement I would say I only need to be sure the earthing is good enough for what I have added, not the whole installation. Plus it says earthing and bonding arrangement for the addition or alteration, if it means the whole system then why does it say that?

- - - Updated - - -

Yhea I guess your right about c2

But some customers do need a proverbial slap round the face - and the dangerous condition does that.

Technically incorrect but if it gets a safer install for them and more importantly covers your ---.......

When you start bending fairly clear regulations to fit customers whims that's when to take a step back.

Of course it's only my opinion.

I won't argue with that! :lol:

 

[spark 68]

I thought this was one of the clearer regs to be honest, as you cannot just pick out a part of the reg that suits you, or more correctly the tight arse customer, you have to take the reg as a whole.

Whether we like it or not, Main Bonding is part of the ADS system.

I usually just include the bonding as part of my quote if it is required, I tell the customer this has got to be done regardless, and if they don't agree then I don't do the work.

 

[brman]

I think that regardless of what they think, if a customer starts arguing with your professional opinion regarding a matter of safety (earthing), then definitely walk. I bet they wouldn't argue with the salesman, when ordering a car, about whether to have a seatbelt fitted just because they don't think it is necessary.

fair enough.

 

[brman]

I thought this was one of the clearer regs to be honest, as you cannot just pick out a part of the reg that suits you, or more correctly the tight arse customer, you have to take the reg as a whole.

Whether we like it or not, Main Bonding is part of the ADS system.

I usually just include the bonding as part of my quote if it is required, I tell the customer this has got to be done regardless, and if they don't agree then I don't do the work.

Am I just picking out part of the reg? I was actually trying to get to what what meant by it overall. earthing is required for ADS I agree but the argument is over whether it needs to be acceptable for the whole system or just the addition/alteration. I am reading it as just the addition/alteration.