NOJA Power OSM Recloser two-pole variant

When implementing protection for two-wire systems, it is important to trip both poles in the event of a fault to ensure the downstream line is completely isolated. Problems occur if only one phase is interrupted, such as downstream earth faults that could be fed from either wire, or downstream phase-to-phase transformers being energised from the uninterrupted side. Electrical engineers must be sure to interrupt both wires in fault conditions.

Historically, protecting two-wire systems was accomplished with three-phase equipment, but the centre phase was left disconnected. While this was a practical solution, this configuration often meant excess expenditure on components that weren’t being used — in this case the centre switchgear pole.

Driven by this market requirement, NOJA Power has developed a two-pole variant of the OSM Recloser.

NOJA Power’s OSM Recloser product can be used to protect single-wire earth return (SWER), two-wire single-phase and three-phase medium-voltage distribution lines. While the switchgear pole configuration may vary, the controller could be identical. This allows utility engineers to standardise on a single control option, while addressing a multitude of distribution network protection applications.