Traction current lines are always equipped with an earth conductor.

The outer sheath is commonly used as a protective earth conductor.

The earth conductor (not shown) is connected through from supply to load uninterrupted.

Screensafe comes with two earth conductors one to be attached to the computer monitor, the other to the keyboard.

These ions are de-ionised by seeking earthed conductors, such as walls and ceilings.

The protective earth conductor in older cables was normally one standard size smaller than the main conductors but is now specified to be the same size.

This is done in the UK because many buildings are supplied with a single phase supply cable where the neutral and earth conductors are combined.

A fault in the appliance which causes a live conductor to contact the casing will cause a current to flow in the earth conductor.

However, it is possible for short circuits to arise between neutral and earth conductors, and between two conductors of the same phase.

This will typically have a value from 40-100 A. Separate live and neutral cables ('tails') go from here to an electricity meter, and often an earth conductor too.

These appliances must have their chassis connected to electrical earth (US: ground) by an earth conductor (coloured green/yellow in most countries, green in the US, Canada and Japan).

In locations where power is distributed overhead and TT is used, installation earth conductors are not at risk should any overhead distribution conductor be fractured by, say, a fallen tree or branch.

In a TN-C system, they would also be very vulnerable to unwanted triggering from contact between earth conductors of circuits on different RCDs or with real ground, thus making their use impracticable.

This makes them useful for testing residual-current devices (GFCIs) because the current drawn will trip most RCDs when the solenoid voltmeter is connected between the live and earth conductors.

In Australia, new installations must also bond the foundation concrete re-enforcing under wet areas to the earth conductor (AS3000), typically increasing the size of the earthing, and provides an equipotential plane in areas such as bathrooms.

In some cases, two earth conductors are used: for example in, Germany, in cases where the traction current line is carried on pylons together with three phase AC current, like the line to the nuclear power station at Neckarwestheim.

Additionally, if the insulation of a live or neutral wire becomes damaged, then the wire is more likely to earth itself on the bare earth conductor and in doing so either trip the RCD or burn the fuse out by drawing too much current.

In the United States National Electrical Code and Canadian Electrical Code the feed from the distribution transformer uses a combined neutral and grounding conductor, but within the structure separate neutral and protective earth conductors are used (TN-C-S).

Mode 1 charging relates to the connection of the EV to the a.c. supply network (mains) utilizing standardized socket-outlets not exceeding 16 A and not exceeding 250 V a.c. single-phase or 480 V a.c. three-phase, at the supply side, and using power and protective earth conductors.