Maintenance/test intervention facilitating device for breaking unit in electrical installation, has transformer with primary and secondary sides connected to harness such that transformer forms secondary power supply

摘要

The device has an isolating transformer (1) parallely connected to a breaking unit associated to a residual differential device (2). The transformer has a primary side connected to a harness in upstream of the unit via a charging circuit-breaker (9) and a voltage presence monitoring device (10). A secondary side is connected to the harness in downstream of the unit and upstream of a load (3) via a phase selecting interface (6), phase inversion device (7) and a coupling device (5) e.g. contactor. The sides are connected to the harness so that the transformer forms a secondary power supply.