Discrimination

[Download Virus]

First post - Go easy!

Advice please - suggestions/best practice.

Domestic property, TNCS supply, 25mm tails to RCBO C/U with 100A main switch.

I want to install a distribution circuit from the aforementioned C/U (I dont want to split tails) to supply a second RCBO C/U (essentially a garage board), serving little more than a lighting and power circuit.

The cable supplying the second board is 10mm T&E and already buried within the fabric of the building and will be used (non negotiable).

with discrimination in mind, what device should I be terminating the 10mm distribution cable, within the second board?

I am using Fusebox boards and the smallest main switch I can see is 63A. This is too big for the 10mm supply cable???

Any advice warmly recieved.

 Thanks

 

[westward10]

We use the term selectivity now.

 

[littlespark]

How did that user name get past the software filters?
If you’re trainee, as profile says, then @Dan can badge you as such


The 10mm cable is protected at the house end by a suitable sized rcbo….

The mainswitch at the garage is just a switch…. Not an overcurrent protection device.

 

[Dan]

How did that user name get past the software filters

Its actually not a blocked name lol I've seen something similar before too. No human trying to get you download a virus would dare to use that name so it's assumed legit.

Apply to Gain Access to Trainee-Only Forum by ElectriciansForums.net - https://www.electriciansforums.net/forums/apply-to-gain-access-to-trainee-only-forum.60/ - apply to access trainee area and wear a trainee badge.

 

[Download Virus]

How did that user name get past the software filters?
If you’re trainee, as profile says, then @Dan can badge you as such


The 10mm cable is protected at the house end by a suitable sized rcbo….

The mainswitch at the garage is just a switch…. Not an overcurrent protection device.

Blimey - that was painless (I anticipated an onslaught of responses).

Thanks Littlespark - appreciated.

Noted re the trainnee forum - I will move over there.

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[littlespark]

This is the point of having a trainee badge... it allows you to ask simple questions without the critism reserved for have-a-go heroes.


Things to think about with the proposal though... You have a 10mm T&E existing... protected by rcbo... which it may have to be depending on how its run.
You would then not technically need rcbos on the outgoing circuits from the second CU, as the supply would be rcd protected anyway.