Meter tails no rcd in stud wall

[newfutile]

During an EICR meter tails were found entering the cavity and coming down a stud wall to a consumer unit about 5 meters (direct distance) away.
they do have an isolator but no rcd or other protection .

as cables buried in a wall have to have (RCD) Residual Current Device at 30mA and generally tails over 3 meters are not permitted by DNO ,how can this comply?

 

[newfutile]

It’s a fairly new build 2017 ,the EIC he left at the property does not mention mechanical protection, also the tails must be 8 -10 meters long

 

[DPG]

It’s a fairly new build 2017 ,the EIC he left at the property does not mention mechanical protection, also the tails must be 8 -10 meters long

Definitely needs a fuse at source then.

 

[Rockingit]

It's the greater than 3m length with no upfront protection that does it.

 

[Pretty Mouth]

I watched that efixx vid, and re-watched it a couple of times, and then had a read through the regs mentioned.

433.3.1(iii), 434.3 (iv), and item (ii) of 434.2.1, these make me think that the tails are not restricted to 3m, as long as they are well protected mechanically, and that the DNO agrees that they are protected by their fuse.

Does anyone know under what circumstances a DNO would agree, or even disagree, to this?

 

[davesparks]

I watched that efixx vid, and re-watched it a couple of times, and then had a read through the regs mentioned.

433.3.1(iii), 434.3 (iv), and item (ii) of 434.2.1, these make me think that the tails are not restricted to 3m, as long as they are well protected mechanically, and that the DNO agrees that they are protected by their fuse.

Does anyone know under what circumstances a DNO would agree, or even disagree, to this?

They'll probably never agree to it, certainly not for small supplies.
I've found that DNO's generally allow between 3 and 4 metres of tails maximum.

 

[newfutile]

thanks for all the interesting input and advice, i also put the same question to NICEIC but im less than impressed with the reply:

---

Good Afternoon,

Thank You For Your Enquiry

Based on the information provided, our guidance is as follows;

There is not a specific regulation within BS7671 which states whether or not supply tails with no RCD protection with a length of run greater than 3metres would result in a satisfactory or unsatisfactory outcome.

Do you feel that there is a safety concern or do you feel that an improvement can be made? Please could you also clarify how the tails have been installed.

Once we get further clarification from yourself than we may be able to assist further with your query.

Regards,

 

[Risteard]

thanks for all the interesting input and advice, i also put the same question to NICEIC but im less than impressed with the reply:

---

Good Afternoon,

Thank You For Your Enquiry

Based on the information provided, our guidance is as follows;

There is not a specific regulation within BS7671 which states whether or not supply tails with no RCD protection with a length of run greater than 3metres would result in a satisfactory or unsatisfactory outcome.

Do you feel that there is a safety concern or do you feel that an improvement can be made? Please could you also clarify how the tails have been installed.

Once we get further clarification from yourself than we may be able to assist further with your query.

Regards,

Their response doesn't seem unreasonable. DNO conditions of supply and BS 7671 requirements are separate issues. It doesn't mean that the installation is not in breach of the former, however.

 

[Baddegg]

End of the day it makes no difference to you wht the outcome of the eicr is….so if concerned give it C2 or fi and put the report to the person paying

 

[DarrenRB]

If tails are ran under plaster & not mechanically protected - they need an RCD.

A 30mA may trip before the board - would a 100mA RCD comply? Surely not???

Mmmm

Daz

 

[DarrenRB]

Cables buried in a wall don't have to have RCD protection, they can have other forms of protection.

As you are carrying out an EICR it is very difficult to confirm whether or not correct protection has been installed. Examination of cables buried within walls, under floors etc is a standard limitation.

You need to make a judgement call as to whether it is likely to comply or not. When was it installed, what is the general standard of the installation, what records are available?

During an EICR meter tails were found entering the cavity and coming down a stud wall to a consumer unit about 5 meters (direct distance) away.
they do have an isolator but no rcd or other protection .

as cables buried in a wall have to have (RCD) Residual Current Device at 30mA and generally tails over 3 meters are not permitted by DNO ,how can this comply?

If tails are ran under plaster & not mechanically protected - they need an RCD.

A 30mA may trip before the board - would a 100mA RCD comply? Surely not???

Mmmm

 

[brianmoooore]

Don't forget that the requirement for RCD protection of buried cables only applies if they are less than 50mm from the surface. If we're talking lathe and plaster on proper 4" studs, there's a good chance they're outside the 'zone'.

 

[DarrenRB]

Don't forget that the requirement for RCD protection of buried cables only applies if they are less than 50mm from the surface. If we're talking lathe and plaster on proper 4" studs, there's a good chance they're outside the 'zone'.

If they’re under 50mm - ie under plaster they should be RCD’d?

But it the RCD is 30mA it’s like having a main switch as an RCD in the board - would a 100mA avoid discrimination?

But still wouldn’t be to regs?

Confused!!!

 

[westward10]

100ma RCD is not deemed to provide additional protection.

 

[Risteard]

If tails are ran under plaster & not mechanically protected - they need an RCD.

A 30mA may trip before the board - would a 100mA RCD comply? Surely not???

Mmmm

Daz

No.

 

[freddo]

The tails to my flushed in consumer unit are in a stud wall for a short section, so to avoid the need for an RCD I put 32mm galv conduit into the stud wall for the tails, bushed into the side of the consumer unit.