T
TonyM58
Ok, been thinking about this for a while, and its gonna probably seem like a really dumb question, but why do we have TT supplies?
Given that the supply transformer is star connected, with the Neutral coming from the star point, which is also strapped to earth, then the TNCS system is perfectly logical, just splitting the Neutral when it comes in to the house and strapping the house MET to it.
Whats bugging me is why that itsnt just done every time. In a TT system surely the connections are the same at the transformer, so why dont we just strap a 16mm earth to the neutral when it comes into the house? Surely this would MAKE it into a TNCS automatically? In fact, why do bother with TNS either? Surely the Neutral and Earth are always electrically the same point at the transformer, so why would we EVER use the higher resistance and less reliable TT earth spike as our return when we have perfectly good earthed neutral coming into the house? There hundreds of old terraced streets in my area which are almost all TT systems, surely they could all be made infintely safer with a couple of foot of 16mm earth cable in each?
Am I missing something fundamental here? Feel free to shout " Doh" at me in a Homer Simpson stylie!
Given that the supply transformer is star connected, with the Neutral coming from the star point, which is also strapped to earth, then the TNCS system is perfectly logical, just splitting the Neutral when it comes in to the house and strapping the house MET to it.
Whats bugging me is why that itsnt just done every time. In a TT system surely the connections are the same at the transformer, so why dont we just strap a 16mm earth to the neutral when it comes into the house? Surely this would MAKE it into a TNCS automatically? In fact, why do bother with TNS either? Surely the Neutral and Earth are always electrically the same point at the transformer, so why would we EVER use the higher resistance and less reliable TT earth spike as our return when we have perfectly good earthed neutral coming into the house? There hundreds of old terraced streets in my area which are almost all TT systems, surely they could all be made infintely safer with a couple of foot of 16mm earth cable in each?
Am I missing something fundamental here? Feel free to shout " Doh" at me in a Homer Simpson stylie!