RNPP-311M-24 is designed for:

• Monitoring acceptable voltage levels
• Ensuring correct phase sequence and absence of phase sticking
• Maintaining phase continuity and voltage symmetry in the network (phase imbalance)
• Disconnecting the load under poor network 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 monitors the neutral indirectly and provides adjustable parameters such as voltage trip thresholds, automatic restart delay (AR), protection trip delay, and selectable monitored network voltage (400 V or 415 V).

After restoring the network voltage parameters, the RNPP-311M-24 automatically reconnects the load following the AR delay.

RNPP-311M can operate in the following modes:

• Minimum/Maximum Voltage Monitoring
• Minimum Voltage Monitoring
• Maximum Voltage Monitoring
• Phase Availability Monitoring
• Monitoring for incorrect phase sequence and phase sticking
• Phase Imbalance Monitoring

Phase Availability Monitoring remains active in all operating modes. In any mode, the relay trips in case of phase loss or if voltage drops below 100 V on one or more phases for a fixed duration of 0.2 seconds.

Output and Contacts:

The device features two groups of independent changeover contacts (1-2-3, 4-5-6). In the "COLD STATE" (device unpowered or disconnected), contacts 1-2 (4-5) are closed, while contacts 2-3 (5-6) are open.

When the load relay trips, it disconnects the load by breaking the power circuit of the magnetic starter coil via contacts 1-2 (4-5). Exception: In the "Maximum Voltage Monitoring" mode, the relay operates with reverse logic.

Advantages:

• Connection via magnetic starter
• Option to disable protective functions
• Changeover contacts for versatility
• Compact design
• Powered by 24V DC
• 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, as well as Automatic Transfer Switch (ATS) cabinets

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 specific protective functions