SWER (single-wire earth-return) is an ultra-low-cost power distribution method that uses a single overhead conductor to supply electricity, relying entirely on the physical ground as the return path to complete the circuit. It is widely used in remote rural networks where running a dedicated neutral or two-phase lines over vast distances is economically unviable. The system requires exceptionally robust earthing electrodes at both the supply transformer and the customer load to function safely.
The fault crew is patrolling the SWER line out to the remote cattle station after a lightning strike blew the isolating transformer.
Because the earth acts as the return conductor, a high-resistance ground connection at a SWER site can cause dangerous step voltages in the soil around the earthing rod.
Also heard as
- single-wire earth-return
Related terms
Earthing
The practice of connecting electrical equipment and systems to the general mass of the earth.
Earth fault
Fault in which a live conductor makes unintended contact with earth or with earthed metalwork.
Line conductor
A wire or cable that carries normal operating current from a power source to a load.