Disconnection times

[EddieB]

On a TNCS system is the disconnection time .4 for all circuits of 32a and below as specified by 411.3.2.2 Table 41.1. I was sure that fixed appliances were rated at 5s ( lights, immersion heaters and the like). Please correct me me if I am wrong

 

[Spudnik]

Because of the need to generally use RCD'd on everything, its now .4 on all circuits.

 

[Guest123]

Hey.

With the need to now protect cables in walls less than 50mm deep not in metal conduit and socket outlets not exceeding 20A etc etc with 30mA RCD and not just socket outlets that may supply equipment outdoors the disconnection times are now 0.4s for all circuits.

There are some exceptions i.e surface wired circuits with dedicated use - fridges/freezers, and correctly labelled can be un 30mA protected.

Cheers.

 

[slocm3105]

Distribution Circuits, and circuits with a protective device of over 32A are 5s discon time if im not mistaken. Below tht its 0.4s. Anyone correct me on that?

 

[Spudnik]

Distribution Circuits, and circuits with a protective device of over 32A are 5s discon time if im not mistaken. Below tht its 0.4s. Anyone correct me on that?

I think this only applies if there is no requirement for RCD protection as 'the loon' pointed out.

 

[andyb]

I think this only applies if there is no requirement for RCD protection as 'the loon' pointed out.

All final circuits not exceeding 32amps have a maximum disconection time of 0.4 sec on a TN system. (table 41.1)

Rcd protection comes under additional protection

 

[ezzzekiel]

Distribution Circuits, and circuits with a protective device of over 32A are 5s discon time if im not mistaken. Below tht its 0.4s. Anyone correct me on that?

yep- what he said