Regs 537.1.4 - Main Linked Switch

[sbelec]

Hi,

I have just been looking at a condition report for a property which is a hostel style home where the main feed is 3 phase into a 3 phase board for distribution throughout the property as single phase 230 volt LNE. Circuits are split between the 3 phases for balance. The electrics are in a locked area for which the staff hold the key.

The regs say that a main switch for operation by an ordinary person, household or similar, shall interrupt both live conductors of a 1 phase supply.

I have 3 phase with a switch operating on only the 3 phases, seperate unswitched nuetral and seperate earth.

Is it a fault or not? I could read it either way - thoughts would be appreciated.

 

[Dizzy_Maskell]

What is the earthing arrangement TT you have to isolate live a neutral. But if not i would say that the three phase supply in a separate locked area should be fine,

 

[telectrix]

agree ^^^^^. a 4 pole isolator is preferred, but can't think of a reg. that insists on it.

 

[sbelec]

Thanks guys, you have confirmed where my thoughts were going.
The system is TNCS, the cutout having 3 fuses a nuetral and earth from it. I know that on 3 phase motor control centres we only ever had 4 wires, 3 x live and a nuetral / earth from the substation and nuetral was never switched as it was also earth. I rarely come across this cross over of 3 phase in a domestic yet controlled environment hence my question but I agree that if I was to be doing a new system I would definately use a 4 pole isolator.

Again many thanks, appreciated.