Voltage, symmetry and phase sequence relay RNPP-313 NTRNP3130

Power Quality Monitoring – Phase Sequence Relay RNPP-313

The RNPP-313 voltage, symmetry and phase sequence relay is a reliable device designed for comprehensive protection of electrical installations. It controls the permissible voltage level, monitors the phase sequence and detects their absence or sticking. The device disconnects the load in case of problems with the voltage quality and automatically switches it on after its restoration. This ensures the continuity of device operation and minimizes the risk of failure.

Functions and application

RNPP-313 is a versatile tool that will work in both professional and home installations. It monitors the phase and voltage symmetry, protecting against the effects of asymmetry. Additionally, it controls the zero crossing and displays information about the status of each phase. The device is particularly useful in places where power supply stability is crucial – in refrigeration, ventilation systems, and in control cabinets with limited space. Thanks to its compact size (only 1 DIN – 18 mm) it is easy to install even in tight conditions.

Adjustment and operating modes

The RNPP-313 relay offers the possibility of adjusting the time delay for protection against phase deviation. After the correct voltage parameters are restored, the device automatically re-switches on the load after a specified APV time. It can operate in several modes:

• Minimum voltage control: disconnection when falling below 195 V
• Maximum voltage control: disconnection when rising above 260 V
• Phase presence control: disconnection when one phase is missing
• Phase sequence and sticking control: disconnection when incorrect connection or phase sticking
• Phase deviation control: disconnection when the voltage difference between phases exceeds 40 V
• Zero crossing control: disconnection when the neutral wire is broken

In each operating mode, the device reacts to a voltage drop below 100 V on one or more phases within 0.25 seconds.

Construction and mounting

The device has an intuitive control method using knobs (regulators). The compact housing with a width of 1 DIN makes it easy to mount on a TH-35 rail. The switching relay allows controlling the load via a contactor (maximum current load determined by the contactor – up to 5A). The use of an impulse power supply ensures resistance to interference in the power supply network.