RNPP-312 is designed for:

• Monitoring acceptable voltage levels
• Ensuring correct phase sequence and absence of phase sticking
• Maintaining phase continuity and voltage symmetry (phase imbalance)
• Disconnecting the load under poor voltage conditions
• Monitoring network voltage after load disconnection and automatically reconnecting once voltage parameters are restored
• Indicating fault conditions and phase voltage availability

This device allows for adjustable settings, including voltage trip thresholds, automatic restart delay (AR), protection trip delay, and selectable monitored network voltage (400 V or 415 V).

It automatically reconnects the load after network voltage parameters normalize, following the AR delay.

RNPP-312 supports multiple modes:

• Minimum/Maximum Voltage Monitoring
• Minimum Voltage Monitoring
• Maximum Voltage Monitoring
• Phase Availability Monitoring
• Incorrect Phase Sequence and Phase Sticking Monitoring
• Phase Imbalance Monitoring

Phase Availability Monitoring remains active in all operating modes. The relay trips in any mode when a phase is lost or voltage drops below 100 V on one or more phases for a fixed duration of 0.2 seconds.

Output and Contacts:
The device includes two independent groups of changeover contacts: NO1-C1-NC1 and NO2-C2-NC2. In the "COLD STATE" (device unpowered), contacts C1-NC1 and C2-NC2 are closed, while contacts NO1-C1 and NO2-C2 are open.

When the load relay trips, it disconnects the load by breaking the power circuit of the magnetic starter coil via contacts NO1-C1 and NO2-C2, except in "Maximum Voltage Monitoring" mode, where the relay operates with reverse logic.

Advantages:

• Connection via magnetic starter
• Option to disable protective functions
• Changeover contacts for versatility
• Ultra-compact size
• Noise immunity due to impulse power supply
• Multiple operating modes

Applications:

• Monitoring phase and line-to-line voltages in three-phase networks
• Protecting three-phase or single-phase equipment from faults such as
• Voltage anomalies
• Incorrect phase sequence and phase sticking
• Phase loss or voltage asymmetry
• Ideal for protecting refrigeration and ventilation systems, Automatic Transfer Switch (ATS) cabinets, and compact control cabinets where space efficiency is crucial

Key Features:

• Monitoring permissible voltage levels
• Phase sequence monitoring and prevention of phase sticking
• Ensuring phase continuity and voltage symmetry
• Disconnecting the load by breaking the power circuit of the magnetic starter coil during fault conditions
• Monitoring network voltage quality after load disconnection and automatically reconnecting the load when parameters normalize
• Option to disable protective functions