Voltage, symmetry and phase sequence control relay RNPP-311.1 NTRNP3111

Three-phase receiver protection with RNPP-311.1

The RNPP-311.1 voltage control, symmetry and phase sequence relay is a reliable device designed to protect three-phase receivers from various failures in the electrical network. Its main task is to disconnect the load in case of incorrect voltage parameters, ensuring protection against damage and downtime. The device constantly monitors the voltage in the three-phase network, comparing it to values set by the user, allowing for a quick response to potential hazards.

Functions and application

RNPP-311.1 measures the values of phase and line voltages, controlling the coil of an external magnetic starter, which switches the load power supply circuit. The relay reacts to:

• unacceptable voltage fluctuations lasting at least 0.02 seconds,
• violation of amplitude symmetry of the voltage (phase tilt),
• phase failure, incorrect phase sequence and phase sticking.

Thanks to this, it finds application in a wide spectrum of installations, especially where power supply stability is crucial – from protecting refrigeration and ventilation equipment to securing industrial cranes and packing robots. This is particularly important in applications requiring continuous operation and minimizing the risk of failure.

Construction and advantages

The RNPP-311.1 relay is characterized by compact dimensions (90.2x36x64.5mm) and mounting on a 35mm DIN rail, which facilitates its integration with existing systems. It has LED indicators of the operating status – separate indicators for each phase and an alarm signaling a failure. Setting the trigger threshold is done using a Unom±% regulator, which provides flexibility in configuration according to the specific requirements of the installation. Made of high-quality materials, it ensures reliable operation in a wide range of operating temperatures (-35…55°C).

Additional advantages:

• easy settings – intuitive threshold adjustment regulator,
• connection via a magnetic starter – a standard solution in industrial installations,
• visual failure signaling – quick problem identification,
• compact size – saving space in control cabinets.
• Relay load status indication (on/off).

The device has SPDT contacts with parameters 250V AC / 5A, which allows controlling various types of loads. It provides effective protection of the installation against the effects of improper operation of the electrical network and extends the life of connected devices.