A system for automatic release of the Reserve (AAR) helps maintain continuity of a power supply, or to consumers in case of failure of main power supply by switching supply a secondary source of energy.

The ARA can be of three types:

• AAR system with two power supplies: Transformer / Generator
• AAR system with two power supplies: Transformer / Transformer (with coupling)
• AAR system with three sources: Transformer / Generator / Transformer

The AAR system component includes the following products in the Schneider Electric:

• Zelio programmable relay (for currents up to 100A) or UA programmable relay (for currents over 100A)
• Range of switches: – Compact NSX (100 A – 630 A)                                                                                                       – Masterpact NT / NW (630 A – 6300 A)
• Separator Interpact (40 A – 630 A)

Features:

• allows switching from the main sourse to the secondary source within a programmable time
• does not allow simultaneous closing of the devices
• status indication by tripping caused by short circuit breakers
• Reset is made manually or automatic

Applicability:

• in institutions where continuity of power supply is vital
• in continuous flow systems
• in areas where electricity supply has problems