Caravan park Earthing

[Bradley6969]

Is TNS permitted on caravan site? I always thought you could use as TNS as supply cable then TT each pitch, spark I’m working with says you can use TNS all way through if ZS is acceptable
Thanks

 

[Nigel]

No not really.
You said ESQCR does NOT allow PME conditions to a static caravan! It does allow it for buildings on parks, not the vans themselves”
BS7671 does not define a static caravan as being a caravan.
It only defines touring caravans as being caravans.
Also, BS7430 which is the earthing COP used by the DNO, considers static caravans as being permanent buildings.

That being said, it doesn’t preclude the DNO from refusing a PME connection to a static caravan, on safety grounds, due to the metal skin.

Of course, all this has nothing to do with the OP’s question regarding whether TN-S can be used throughout a caravan site.
The simple answer being yes.
The proviso being that it should be determined first, whether PME conditions apply.
If PME conditions do apply and the site caters to touring caravans, the hook ups would have to be TT.

How can PME conditions apply to a TN-S? The clue is in the name.

 

[richy3333]

They don’t and Spin didn’t say they did?

 

[DPG]

It got confusing because the thread was initially only asking about a TNS supply, but then it got diverted down the PME road.

 

[Deleted member 26818]

Let me try to put this in simple terms.
PME conditions apply, when the supply neutral is earthed at multiple points.
The supply to an installation can be TN-S or TN-C-S, doesn’t matter.
The neutral and earth do not have to be combined for PME.

 

[Ian1981]

A good debate going, keep it respectful
Some interesting points of discussion, having had not much to do with caravan parks so never bother looking at the relevant parts in part 7 much.

 

[bigspark17]

708.441.4
Page 265!

 

[Deleted member 26818]

708.441.4
Page 265!

See my post #27.
Then my post #20.

 

[bigspark17]

See my post #27.
Then my post #20.

Im on my monile so dont know what posts are what, but you said pme is allowed to a static caravan!! 708.441.4 clearly states it isnt allowed! ESQCR is law not guidance!

 

[bigspark17]

See my post #27.
Then my post #20.

Do you work on caravan parks?

 

[Deleted member 26818]

Im on my monile so dont know what posts are what, but you said pme is allowed to a static caravan!! 708.441.4 clearly states it isnt allowed! ESQCR is law not guidance!

Problem here, is what constitutes a caravan.
There are touring caravans which can be towed by vehicles on the public highway, and there are static caravans which although they may have wheels and a tow hitch, cannot be towed by vehicles on the public highway.
Another name for static caravans would be mobile home.

When BS7671 makes reference to caravans, it is referring to touring caravans.
Here’s the definition:
Caravan. A trailer leisure accommodation vehicle, used for touring, designed to meet the requirements for the construction and use of road vehicles (see also definitions of Motor caravan and Leisure accommodation vehicle).

Here’s the definition for a mobile home/static caravan:
Mobile home. A transportable leisure accommodation vehicle which includes means for mobility but does not meet the requirements for construction and use of road vehicles.

BS7430 the COP for earthing used by the DNOs considers static caravans to be permanent buildings.

This is taken from the most up to date UKPN Earthing Design Standard for LV installations:
5.9 Mobile Homes
A PME earthing terminal may be provided to mobile homes if the following criteria are satisfied:

• The mobile home is permanently sited.
• The mobile home is permanently connected to water and sewerage services.
• The installation is constructed such that a person in contact with the general mass of earth cannot touch any metalwork connected to the earth terminal.
• The installation complies with the earthing and bonding requirements of BS 7671.

If these conditions cannot be satisfied the mobile home shall be treated as a caravan in accordance with Section 5.6.
Refer to BS 7671:2018 Section 721 for the earthing and bonding requirements.

 

[Deleted member 26818]

Do you work on caravan parks?

I have done, and have also worked on mobile home sites.

 

[Nigel]

Problem here, is what constitutes a caravan.
There are touring caravans which can be towed by vehicles on the public highway, and there are static caravans which although they may have wheels and a tow hitch, cannot be towed by vehicles on the public highway.
Another name for static caravans would be mobile home.

When BS7671 makes reference to caravans, it is referring to touring caravans.
Here’s the definition:
Caravan. A trailer leisure accommodation vehicle, used for touring, designed to meet the requirements for the construction and use of road vehicles (see also definitions of Motor caravan and Leisure accommodation vehicle).

Here’s the definition for a mobile home/static caravan:
Mobile home. A transportable leisure accommodation vehicle which includes means for mobility but does not meet the requirements for construction and use of road vehicles.

BS7430 the COP for earthing used by the DNOs considers static caravans to be permanent buildings.

This is taken from the most up to date UKPN Earthing Design Standard for LV installations:
5.9 Mobile Homes
A PME earthing terminal may be provided to mobile homes if the following criteria are satisfied:

• The mobile home is permanently sited.
• The mobile home is permanently connected to water and sewerage services.
• The installation is constructed such that a person in contact with the general mass of earth cannot touch any metalwork connected to the earth terminal.
• The installation complies with the earthing and bonding requirements of BS 7671.

If these conditions cannot be satisfied the mobile home shall be treated as a caravan in accordance with Section 5.6.
Refer to BS 7671:2018 Section 721 for the earthing and bonding requirements.

This thread has turned into a car crash. Spin you are so off it is silly.

Section 708 of BS 7671 is for ‘Electrical Installations in Caravans / Camping Parks And Similar Locations’.

Section 721 deals with wiring inside caravans or motor caravans but that is not what we are talking about. Section 708 is the relevant section.

Regulation 708.411.4 states:

The Electricity Safety, Quality and Continuity Regulations (ESQCR) prohibit the connection of a PME earthing facility to any metalwork in a leisure accommodation vehicle (including a caravan).

This does not preclude the use of a PME earthing facility as the means of earthing for other purposes, such as to the installations of permanant buildings.

How you can be in here justifying a PME to a metal caravan just because it does not have wheels is ludacris.

Just accept you are completely incorrect and then move on.

 

[Nigel]

I have done, and have also worked on mobile home sites.

Best go back and put your work right then.

 

[Nigel]

It got confusing because the thread was initially only asking about a TNS supply, but then it got diverted down the PME road.

Yes because Spin seems to think PME conditions can apply to a TN-S supply so took the thread way off track.

 

[Deleted member 26818]

This thread has turned into a car crash. Spin you are so off it is silly.

Section 708 of BS 7671 is for ‘Electrical Installations in Caravans / Camping Parks And Similar Locations’.

Section 721 deals with wiring inside caravans or motor caravans but that is not what we are talking about. Section 708 is the relevant section.

Regulation 708.411.4 states:

The Electricity Safety, Quality and Continuity Regulations (ESQCR) prohibit the connection of a PME earthing facility to any metalwork in a leisure accommodation vehicle (including a caravan).

This does not preclude the use of a PME earthing facility as the means of earthing for other purposes, such as to the installations of permanant buildings.

How you can be in here justifying a PME to a metal caravan just because it does not have wheels is ludacris.

Just accept you are completely incorrect and then move on.

The fact that you are unwilling to accept the evidence presented to you, or that of your own eyes does not mean that I am incorrect.