Recent content by Sergeant

Thanks， it's clear to me! :P and can you tell me does the lighting need RCDs protection in TT system， we all know that sockets outlets need RCDs protection in TT system. But for lighting, I don't find any British or IEC standard to clarify this issue. So, what's the...

[/url] You mean that the substation do not have the conception of TT or TN system and it's nothing with the consumer's earthing system?

Is that cool? Big earth, small internet!

BS7671 is also from IEE Wiring Regulation 17th So，that is, the earthing system of consumers is nothing with that of substations?

Can anyone tell me that is there any connections with the earthing system between substations and consumers? Such as the substation use TT system, the consumers use TN-C-S, or TN-S, or TT. Is there any imperative rules to define that in 17th?

If the 30/11kV Substation and 11/0.4kV substation choose TT system， can the earthing system of residential buildinguse TN-S or TN-C-S? Generally, the earthing system of the substation and consumers can be different?

That we design a project with British Standard outside CHN. We also need to use the 17th.

In the TT system, we all know that the socket outlets must be protected by RCCB, RCBO or ELCB. But for the lighting, is that necessary or forced that should be protected by RCBO? Is MCB ok? :twisted: