Garage Consumer unit question

Gringro

Hi All,

I'm looking for some advise.

I am wiring up a garage. There is an SWA from the house to the garage. On the house side the SWA is connected to a 63AMP singe pole switch fuse. When installing the Consumer unit in the garage, I am wondering if I need to add a 2 pole RCD, or is the 63AMP singe pole switch fuse in the house enough for isolation.

Appreciate any advice

JL spark

please get someone qualified to do this ,

You haven’t a clue,

Gringro

Hi JL Spark,

I appreciate you pointing me towards someone qualified, but your being a bit cruel in saying that I dont have a clue.

I have wired 2 houses and am qualified in electronics. I'm obviously not a spark, if I was, I would know the answer.

I noticed that you did not have a clue about PV, but a lot of people were kind enough to you and helped you when you first posted basic questions about PV.

I'll admit that the naming of the 63AMP singe pole switch fuse may be confusing, so I have added a couple of pictures.

If you, or anyone else is kind enough to provide advice, it would be appreciated.

JL spark

Wired two house's (who certified them ) , so that makes you think you can take a cover of a DB , you do know if you where reported doing this , you can land with a 15k fine ,

Lenar3556

https://www.boards.ie/discussion/2058370165/garage-consumer-unit-question

63A is quite a high overcurrent protection for a supply to a domestic garage. This would need a cable size of at least 16mm2 - So step one is to check if the 63A switch fuse is suitable to protect the installed cable in the first instance.

Within the garage, there will need to be a sub board fitted which will need to have RCD protection for each individual sub-circuit. I.e Lights, Sockets etc. which will be wired to this. The best way to achieve this is to use RCBO’s within this new consumer unit.

Note that this type of work should, under current regulations, be carried out only by a registered electrical contractor. If you do decide to carry it out yourself, it would be worthwhile to have it tested by a registered electrical contractor thereafter.

2011

https://www.boards.ie/discussion/2058370165/garage-consumer-unit-question

A few points:

1. Work out what size SWA cable has been installed, i.e. is it a 3 x 6 mm sq. ?
2. Measure how long the cable run is.
3. Calculate the design load for the garage.
4. Select a protective device and rating for the SWA. This should have a higher rating than the design load. As stated in the above post a 63A rating would not make sense.
5. Confirm that the cable has sufficient current carrying capacity for the selected protective device based on the cable size and length of run. You will need to check volt drop and earth fault loop impedance.
6. Work out how you will earth the armour of the SWA. Normally this is achieved by using an SWA gland at both ends of the cable and glanding into a metal enclosure and then earthing the enclosure.
7. Will the cable reach a good location for the sub-distribution board?
8. It would not make sense to install a double (or single pole) pole RCD on the sub distribution cable in the house.
9. As stated in the above post an RCBO per circuit in the sub-board would be best.

No offence intended but as someone that has a qualification in electronics I know this is of little value when designing domestic wiring.