Running network cable (cat 5) with twin and earth help

[JohnW2]

That does not seem at all unreasonable to me, AIUI DC is generally more hazardous than ac of the same voltage.

I agree - but, as I've said, BS7671 is inconsistent with that "reasonable" approach by saying that RCDs are regarded as an acceptable means of "additional protection" only "in AC systems" and, more specifically, restricts the requirement for RCD protection of sockets to only those in "AC systems".

Hence, it would seem that the requirement for RCD protection of buried LV cables (without excluding cables carrying DC LV) is the only case in which BS7671 is "reasonable", it being fairly "unreasonable" in all other cases.

Mind you, this is probably all pretty moot, since I think one would probably struggle (these days) to find a DC LV electrical installations!

Kind Regards, John

 

[bernardgreen]

I don't really understand that. A DC RCD will surely work just as well if, as with the familiar use of RCDs with AC installations, it is one side of the (not centre-tapped) supply that "the DC might leak to" , won't it?

I think you are right.

 

[DetlefSchmitz]

since I think one would probably struggle (these days) to find a DC LV electrical installations!

I think you need to consider PV installations...

 

[JohnW2]

I think you are right.

Thanks. I'm glad you agree.

Kind Regards, John

 

[JohnW2]

I think you need to consider PV installations...

Good point. However, as far as I am personally concerned, domestic PV installations are something that I never 'consider', and quite probably never will

Kind Regards, John