Ah..,Yep? No? maybe geez... im lost,this is all pretty new to me. I have been installing security systems for the last 12 years.
I know the max you can get from one phase and neutral is 230v(phase voltage) to get 400v(line voltage) you'd need at least two phases add a neutral and you would have the option of 2 times 230v ..the following is from one of my Text books; Multiple Earth Neutral System, This system of distribution uses the multiple earth neutral or MEN system.the neutral conductor is earthed at the source of the supply and also at one or more other points along the distribution line, and each consumers premises. the resistance between any point of the neutral conductor and earth must not exceed 10 ohms. The neutral is multiple earthed so that, if any live part of the supply system or consumers distribution system comes into contact with earth, current flows back to the neutral by way of parallel paths,and the net resistance of the fault current is low. the lower the resistance of the fault path, the higher the fault current - quick opperation of fuse or circuit breaker.
ADVANTAGES; 1. the greatest voltage to earth at any part of a consumers installation is phase voltage 230 volts
2. parallel low resistance paths are provided for fault current
3. the resulting high value of fault current ensures that protective devices operate effectively.
4. if a customers neutral is broken fault current can still flow back to the point of supply through parallel earth and neutral connections at other premises
5. some protection is provided from lightning and high voltage flashovers
DISADVANTAGES
1. the high fault current drings increased risk of fire or shock if it flows through poorly made connections or joints.
2. A broken neutral is sometimes not noticed because the earthing system carries the neutral current.
3. all exposed metalwork assoicaited with wiring systems must be earthed.
