Power point in external glasshouse

[cliffed]

Client wants 2g socket in greenhouse, obviously IP rated,will be supplied from Rcd, the greenhouse consists of metal frame work on the ground.
Does this require MPBC

 

[cliffed]

Nice discussion agree & disagree on so many issues…typifies the interpretation of each of us on actually how to be compliant.
This all for a 2g power point, from an existing external radial circuit 2.5mm.

 

[cliffed]

But both 544.1.1 and 54.8 have the caveat "except where PME conditions apply"

That is the crux of the matter.

I take it to mean if the conductors are part of the PME system (i.e. the combined part) then table 54.8 and 10mm^2 or 6mm^2 etc do not apply, and no figures are specified within the wiring regs.

In all other cases - where the conductors have been separated (after the service head) then the conditions in table 54.8 and 544.1.1 are applicable.

If it did just simply mean "except for PME" then that would be the wording.

Why write the clause as particular to PME conditions, if they didn't mean where it is part of the PME (TN-C ) aspect.

Taking "except where PME conditions apply" to mean you can't use that table or regulation when dealing with part of the PME system fits the words, and the fact that the bonding size isn't specified.

Taking "except where PME conditions apply" to mean that the bonding size in the regulation and table isn't applicable to an installation supplied by a PME system begs the questions 1) what cable size should be used as 54.8 is "except where PME conditions apply" so what size for PME; and 2) why the "odd" wording, why not just say 'except for installations supplied from PME"?

Except..
where the cross sectional area required not less than half…..
Except..
where highway furniture…..
Where PME conditions the MPBC in accordance with the PEN Table 54.8
Where an installation has more than…..MPBC Sselected to the largest PEN of the supply
Must say a 2 year old could write this better & most probably understand it better too.

 

[mainline]

Except..
where the cross sectional area required not less than half…..
Except..
where highway furniture…..
Where PME conditions the MPBC in accordance with the PEN Table 54.8
Where an installation has more than…..MPBC Sselected to the largest PEN of the supply
Must say a 2 year old could write this better & most probably understand it better too.

It looks to me like nothing has changed apart from the wording.

How far away is the greenhouse ?

Explain to the customer how much easier it would be to use an extension lead

 

[cliffed]

It looks to me like nothing has changed apart from the wording.

How far away is the greenhouse ?

Explain to the customer how much easier it would be to use an extension lead

Beauty… extension leads with a IP …SPD…Rcd…AFDD & free bogof bonding clamp

 

[mainline]

Beauty… extension leads with a IP …SPD…Rcd…AFDD & free bogof bonding clamp

Probably some Chinese kit already on the shelf at Aldi

 

[Julie.]

Yes, my apologies, I had read that both aspects were except PME, but it in fact is the same as previously, 54.8 applies to PME, and the first part of 544.1.1 to non-PME; it is only that portion which has changed to allow smaller bonding size for additional buildings.

My fault entirely.

 

[cliffed]

Yes, my apologies, I had read that both aspects were except PME, but it in fact is the same as previously, 54.8 applies to PME, and the first part of 544.1.1 to non-PME; it is only that portion which has changed to allow smaller bonding size for additional buildings.

My fault entirely.

Great confusion eliminated

 

[westward10]

Took a fair bit of deliberation on my part before I finally said I don't see it that way Julie, I then hid behind the sofa

 

[Julie.]

Took a fair bit of deliberation on my part before I finally said I don't see it that way Julie, I then hid behind the sofa

If I am wrong, I am wrong, no issues with that.

I looked right through the changes when I got the new version, but obviously didn't digest it all properly.

 

[UNG]

After 84 posts can he fit the socket yet

 

[mainline]

After 84 posts can he fit the socket yet

Customer cancelled, they said he spent too much time on his phone

 

[cliffed]

After 84 posts can he fit the socket yet

Think I’ll give it a miss

 

[LastManOnline]

Does this require MPBC

No.

Why? MPBC assumes the extraneous part can.....

1) introduce a potential (yes)
2) introduce heat damaging currents. (No)
3) can be simultaneousely touched with other extr. metal (No)



Does it require supplementary bonding? Yes

Why? A class 1 appliance may be plugged in to the powerpoint

 

[cliffed]

No.

Why? MPBC assumes the extraneous part can.....

1) introduce a potential (yes)
2) introduce heat damaging currents. (No)
3) can be simultaneousely touched with other extr. metal (No)



Does it require supplementary bonding? Yes

Why? A class 1 appliance may be plugged in to the powerpoint

It an extraneous & needs bonding with the appropriate sized conductor

 

[cliffed]

No.

Why? MPBC assumes the extraneous part can.....

1) introduce a potential (yes)
2) introduce heat damaging currents. (No)
3) can be simultaneousely touched with other extr. metal (No)



Does it require supplementary bonding? Yes

Why? A class 1 appliance may be plugged in to the powerpoint

It an extraneous & needs bonding with the appropriate sized conductor