This is a Vigi add-on module for ComPact NSX 100/160 that provides residual current protection. It is used for 4-pole circuit breakers. The operating voltage is between 440 and 550 VAC 50/60 Hz. The differential current sensitivity is adjustable from 30 mA to 30 A. It is plugged directly onto the device connection terminals and directly activates the release in the event of a fault due to residual current. This Vigi add-on module is internally powered by the voltage of the distribution network, even if it is only powered by 2 phases. It complies with the IEC 60947-2 standard, Annex B.