Wouldn't it be simpler if electrical systems take away the neutral and just have live and ground similar to electronic systems?

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    \$\begingroup\$ What would be the point? \$\endgroup\$ – Leon Heller Dec 28 '16 at 13:22
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    \$\begingroup\$ Electrical systems are designed for safety because of the lethal voltages involved Most electronic systems use non-lethal level voltages. \$\endgroup\$ – Barry Dec 28 '16 at 13:26
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    \$\begingroup\$ Wouldn't it be simpler Nope, because the neutral and ground, although connected, serve different purposes. The neutral is used to conduct the returning current from the live wire. So if 1 Ampere flows through the live wire, 1 Amp must also flow through the neutral. It could flow through the ground but is not allowed and also dangerous. The ground is used for as the name says grounding devices. It provides a connection to a "voltage free" point which is safe to touch. If the "live" current "escapes" through the ground (so not through neutral) something is wrong and a breaker trips. \$\endgroup\$ – Bimpelrekkie Dec 28 '16 at 13:28
  • \$\begingroup\$ @FakeMoustache you should have put that up as an answer \$\endgroup\$ – RoyC Dec 28 '16 at 14:53

Wouldn't it be simpler if electrical systems take away the neutral and just have live and ground similar to electronic systems?

Ground is localized to a house or installation. Ground is not provided by the electricity companies because that would be unsafe - how could a safe ground be sourced from an electrical generator hundreds of miles away?

How could you detect if current was flowing through some unfortunate person (in the process of being electrocuted) if one of the power feeding wires is actually ground - how could you tell that the current was flowing through that person without a neutral wire? How would you distinguish it from normal load current?

That's the whole purpose of residual current devices (UK name) or ground fault current interrupters (USA name): -

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The reason we seperate Neutral and Earth is safety.

Consider what happens when a wire breaks.

In a seperate neutral and earth system

  • If the neutral breaks the appliance stops working, but there should be no hazard to the user.
  • If the earth breaks then it can no longer protect against short circuits to the case but assuming there are no other faults it is not immediately dangerous.

In a combined neutral and Earth system.

  • If the combined neutral and earth core breaks the case immediately becomes live via the load.

Most electronic systems don't have this issue because the voltage is too low to present a significant hazard.

  • \$\begingroup\$ Another important factor is that current-carrying conductors may have a non-zero voltage drop. Especially when using devices whose inrush current is significantly above their operating current, the neutral wire of a device might have a few volts on it. While that might not sound like much, suppose a device with a 0.1 ohm path to the panel through the neutral wire, and a one-ohm path through something else, momentarily draws 11 amps. That would feed one watt of power into the one-ohm path, which could be enough to make it dangerously hot. \$\endgroup\$ – supercat Jan 9 '17 at 18:39

Actually your assumption is wrong. In electronics where there are signals on cables that need protection in either direction of radiation, we have 3: power/signal, common and shield.

Shield is necessary to shunt leakage and stray currents for the same reason Earth ground is provided in ac power service for human safety and reduce radio noise. Otherwise double insulation is used for safety on 2 pronged units.

In some countries where 3 phase power is offered there is no grounded Neutral.

The purpose of a GFCI ( ground fault circuit indicator) is to detect power leakage currents and break the circuit open. Often humidity in bathrooms can trip this due to high sensitivity. It does not work by sensing ground current rather as a differential relay operating from very small current differential between Line and Neutral. The theory being, if they are not equal and opposite, then there must be some leakage.


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