bigfranky145
Member
Is it possible to have a separate smaller consumer unit for the garden coming off the main consumer unit?
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
Theoretically yes, although there are limited circumstances where that would be necessary as opposed to the (sometimes easier) alternatives. Also, installing a new CU isn’t really a job for a DIYer.
You really need to give us a bit more information on what you’re trying to achieve, and why you want a secondary CU.
Thanks - I was more asking theoretically before I ask an Electrician.
The house has a "supply" to the exterior which was installed fairly recently connected to the CU and terminating in a box but "capped".
I had wondered if I would need a secondary CU to have external sockets & lights hooked up to rather than take the supply from the main CU
What's the rating of the breaker feeding the cct?
Might help if you could direct me as to the applicable Regulations in BS7671.Don't sound promising here. I know I keep banging on about this but circuits feeding equipment outside the zone protected by the equipotential bonding will have a shorter disconnection time than those in the zone (house). To ensure this on alny supply type, it is advisable not to export the CPC from the supply, but to use an earth electrode locally to the new CCU and fit a 30mA rcd to protect all circuits. If the CCU is in a damp area it should be non flammable non metallic as would be used in agriculture and horticulture.
Don't sound promising here. I know I keep banging on about this but circuits feeding equipment outside the zone protected by the equipotential bonding will have a shorter disconnection time than those in the zone (house). To ensure this on alny supply type, it is advisable not to export the CPC from the supply, but to use an earth electrode locally to the new CCU and fit a 30mA rcd to protect all circuits. If the CCU is in a damp area it should be non flammable non metallic as would be used in agriculture and horticulture.
Thanks - I was more asking theoretically before I ask an Electrician.
The house has a "supply" to the exterior which was installed fairly recently connected to the CU and terminating in a box but "capped".
I had wondered if I would need a secondary CU to have external sockets & lights hooked up to rather than take the supply from the main CU
Might help if you could direct me as to the applicable Regulations in BS7671.
use of TNCS earthing is not recommended in BS7671 Section 705
Not really sure how that is applicable. #8 refers to shorter disconnection times, outside zones etc.....As the DNOs will tell you, use of TNCS earthing is not recommended in BS7671 Section 705 due to the reasons that Bob gave. See 16.4 in the SP Energy guidance
https://www.spenergynetworks.co.uk/userfiles/file/EART-01-002.pdf
Some DNOs may just refuse to connect a new supply depending on the circumstances.
Unless carefully planned and specified, use of a DNO TNCS earth is not a good idea for a garden installation.
It is a bit of a mess unfortunately. It used to be in the PME Regulations, which were a supplement to the old Supply Regulations, and were both Statutory Documents. Unfortunately, when the UK government of the day wrote and implemented the ESQCR regulations, the PME regulations were forgotten about and not included. They do still exist very much in the "DNO World" for ensuring connections to the public supply are safe, and have had to be incorporated into the various DNOs Technical Guides, which in general are for DNO staff only, albeit a few DNOs have made their various Technical Guides available on the internet.. . . I am interested where this is referenced.
And how do the DNO "police" the installation after their meter and how is it their business?It is a bit of a mess unfortunately. It used to be in the PME Regulations, which were a supplement to the old Supply Regulations, and were both Statutory Documents. Unfortunately, when the UK government of the day wrote and implemented the ESQCR regulations, the PME regulations were forgotten about and not included. They do still exist very much in the "DNO World" for ensuring connections to the public supply are safe, and have had to be incorporated into the various DNOs Technical Guides, which in general are for DNO staff only, albeit a few DNOs have made their various Technical Guides available on the internet.
It is a bit of a mess unfortunately. Unfortunately, when the UK government of the day wrote and implemented the ESQCR regulations, the PME regulations were forgotten about and not included.
Not really sure how that is applicable. #8 refers to shorter disconnection times, outside zones etc.....
I am interested where this is referenced.
The ESQCR makes it their business. My employer (a DNO) insists on a Test Certificate from a person or company registered as "Competent" for Building Regulations "Part P" signoff for a new property, re-wire of an existing property, or certain other specified works such as solar, battery or wind generation. No certificate, no supply. Simple.