Meter box rules and a reg ref?

[hobbles]

Hi all, can anyone point me in the right direction for a reg reference on meter boxes especially adding a new sub main from Henley blocks to serve a new C/u. Is this BS7671 or Supply regs?

Not up on domestic subs, for example twin meter box scenario back to back, one side has service fuse in it and a C/u for an Arga, in other meter box 2 x C/u. We are looking to fit a PV 2 way C/u, with a 20A RCBO with post gen meter in series. Room is tight and I am getting info such as:

1.Nothing should be in service fuse side, (this side has romm to fit PV C/u)
2. All cables must be D/I and/or in trunking/protected throughout
3. No obstructing any meter or DNO equipment when installing
4. Entry /Exit of cables into the meter box, maintaining IP integrity
5. It is in a lockable box with a special key to open

Thanks

 

[PrenticeBoyofDerry]

Anything connected beyond the meter tails are your responsibility and BS7671:2008 should be complied to as should any relevant building regulations (mainly part p)
What is the total demand on the system?
what is your main fuse rating?
Do you have RCD protection?
Size of earthing and main bonding conductors?
Earth arrangement?
All things to be considered when upgrading or alterations are being made.
If you are restricted for space, would be worth considering the replacement of existing DBs/CUs for more suitable enclosures.

 

[DetlefSchmitz]

Why use an RCBO on the PV submain? Is the cable hidden in the wall?

 

[hobbles]

All relvent supply characteristics have been assessed, thats not a prob thanks.

As a company we fit RCBO's on all PV inverter ccts. Its also there for overload & fault protection on the externally routed swa feeding the inverter 70mtrs away in a remote building. Otherwise I would have the potential of the full house supply of at least 63A going down it and obviously the nature of the installation around a garden perimeter. ADS

I am after more specific selection & erection rules in the meter box itself, obstruction of supply authority kit, space and access.

Our Tech director advised me to put C/u on service fuse intake side of meter box and one of my collegues said that was not allowed?

I like to do things right, to regs and once only regardless of my Tech directors design.

Any advice welcome

 

[Taylortwocities]

The box with the meter in it is reserved for DNO's equipment only.

It is usually stencilled on the backboard.

 

[Adam_151]

As a company we fit RCBO's on all PV inverter ccts. Its also there for overload & fault protection on the externally routed swa feeding the inverter 70mtrs away in a remote building. Otherwise I would have the potential of the full house supply of at least 63A going down it and obviously the nature of the installation around a garden perimeter. ADS

No one is suggesting for one moment that your should connect the circuit into the incomming side without protection . We are just wondering how you see an RCBO as opposed to an MCB is necessary in this situation.

Does your inverter have a transformer between the AC and DC sides, or if its a transformerless model, does taht manufacturer state that the inverter is incapable of feeding DC into the AC side. It it is transformerless and does not come with such assurances then a standard RCBO is not going to be sufficent (DC can disable standard RCD/RCBOs) you'd need B type rcd protection

 

[redpis]

The box with the meter in it is reserved for DNO's equipment only.

It is usually stencilled on the backboard.

I challenged the above with my supplier as I wanted to put an generator input mounted to the external intake board, they put forward no objection when I said as I own it, they would have to leagally adopt the meter box in order to maintain exclusivity of use.

 

[JohnW2]

I challenged the above with my supplier as I wanted to put an generator input mounted to the external intake board, they put forward no objection when I said as I own it, they would have to leagally adopt the meter box in order to maintain exclusivity of use.

.
Interesting. Are you sure you own the backboard as well as the box - does it (the backboard) have any indication of ownership on it?

Kind Regards, John

 

[redpis]

I challenged the above with my supplier as I wanted to put an generator input mounted to the external intake board, they put forward no objection when I said as I own it, they would have to leagally adopt the meter box in order to maintain exclusivity of use.

.
Interesting. Are you sure you own the backboard as well as the box - does it (the backboard) have any indication of ownership on it?

Kind Regards, John

Sure, its the same as this one:

http://www.meterboxes.co.uk/content/PDF Files/M01023.pdf


Things might be different if the supplier installed the meter board, but in my case it belongs to the homeowner.

 

[hobbles]

Yes the inverters have transformers for total segregation of AC/DC, and yes type B RCD is the guidline from the Dti guide, the company I work for opt for type B RCBO's.

Back to the original post is there a reg/spec/guide specifically for do and dont's in meter boxes?

 

[Adam_151]

and yes type B RCD is the guidline from the Dti guide company I work for opt for type B RCBO's.

Not sure I've seen a rcbo with a type B rcd unit? Surely it would be easier to use type B rcd in conjuction with MCB as I can imagine the RCBO version would be excessivly expensive?

 

[Roo]

I challenged the above with my supplier as I wanted to put an generator input mounted to the external intake board, they put forward no objection when I said as I own it, they would have to leagally adopt the meter box in order to maintain exclusivity of use.

.
Interesting. Are you sure you own the backboard as well as the box - does it (the backboard) have any indication of ownership on it?

Kind Regards, John

Sure, its the same as this one:

http://www.meterboxes.co.uk/content/PDF Files/M01023.pdf


Things might be different if the supplier installed the meter board, but in my case it belongs to the homeowner.

I understand both sides to the ”Can I fit on the DNO board question”.
The main reason I say no is because when I come along to fit a different metering setup that requires more room, I can't do it and have to refuse the customer the tariff.

 

[westie101]

Added to that when the board needs changing it means the DNO has to get the customer to remove any of their equipment from it at their cost, or if the customer wants to change the board we need to remove our stuff at the customer's cost.
Keep to seperate boards for DNO/supplier and customer equipment!

 

[redpis]

The first picture shows a consumer owned kit within a meter box, ideally I would agree that you should keep thing seperate for ease.

http://www.eon-uk.com/downloads/m7149_positioning_of_commercial_connections.pdf

 

[Roo]

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