TN-C-S in Need of Earth?

If you were using the "NEC as your code reference, you would be required to have the neutral and the grounding electrode conductor bonded in the main panel at the first over current device just as you have at your location. If you are required to have a GFI(ground fault indicator) it is necessary that the phase conductor and the neutral pass thru the GFI for it to operate properly. Check this link for you information.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/gfi.html

OK, so from what you say- GFI is what we would call an RCD or RCCB.

But what would be the consequences if any, if you separated the N and E in the consumer box without a GFI type device?

I can only see it being safer by having it separate anyway.

All input is welcome.

Thank you for your comment.

TB

<...But what would be the consequences if any, if you separated the N and E in the consumer box without a GFI type device?...>

The E must to be bonded to the N upstream of the GFI/RCD/RCCB and not downstream of it, otherwise the device won't operate in the event of a fault thereby placing the user at greater risk during the fault event.

If in doubt, consult a qualified electrician.

If there is NO GFI type device, then removing the link that is in the box between the N and E would have what effect?

I plan to install a 4pole RCD (as it is 3 phase + neutral) so that the whole system would be safe.

I don't want the Ground and Neutral connected at all, because I was never taught that this was a good thing.

So what I plan is -

Earth Rod 2m deep, direct to Consumer unit. Remove link between N and E which is in the consumer unit. Move the 3phase +N to go direct into a 4pole 30mA RCD then back into the Consumer Unit. There are just the 4 wires in, so the N must connected to the E before I get a chance to even split it afterwards.

Does this sound ok?

Thanks for the responses so far.

TB

I think what you have is what we call MEN System (multiple earth neutral) this system is used in most countries around the world and has proved its self to be most reliable. RC-D's (residual current devices) are a relatively new player on the market, I suppose here in New Zealand they have to be installed in new installations for the past 10 years or so. But i don't think that there has been are requirement to upgrade existing installations unless work is done within the sw bd or a new appliance outlet is installed.

I am sure that what you have is the MEN system and it has not been upgraded, and i would expect that in Thailand. It is still a reasonably safe system, the only reason that we have RC-D's now is that the technology is available and they don't cost a fortune for a bit more additional safety.

How would I know if it was a MEN system?

The house is about 5 years old. I know they are way behind modern electrics here but it was supposedly built by a German Thai company, using quality electrics. Looking at them now, I somehow believe they didn't have much of an idea of what they are doing. The Consumer box is made up from all the colours of the rainbow in cable form....

White, Black, Red, Blue and green. Really weird to look at a system like that, but that is how they do it here. Atrocious.

TB