RNPP-311M voltage monitoring relay is designed for protection of three phase loads against major types of mains faults, such as:

• RMS voltage reaching beyond admissible thresholds – over and under voltage
• Phase loss or Single phasing
• Phase sequence order violation or reverse phase sequence
• Phase coincidence or shorting of two or more phases
• Phase Imbalance or asymmetry

The device performs monitoring of the main circuit parameters and de-energizes (trip) load when the parameters fall beyond specified boundaries.

The front panel LEDs display the following:

• Presence of true RMS voltage in the mains
• Load status (On/Off)
• Type of fault

Adjustment potentiometers allow for setting:

• Tripping threshold for the minimum/the maximum voltage, (% of the rated voltage)
• Time delay for load re-energizing (reset) after the circuit parameters recovery
• Tripping time delay for load de-energizing (trip) in case of all circuit voltage faults

RNPP-312 has been designed:

• for monitoring the permissible voltage level;
• for monitoring the correct alternation and absence of sticking of phases;
• for monitoring the full-phase and symmetry of the mains voltage (phase imbalance);
• to disconnect the load in case of improper mains voltage and neutral failure;
• for monitoring the quality of the mains voltage after switching off the load and automatically turning it on after restoring the voltage parameters;
• to indicate the failure in the event of emergency situation and the presence of voltage in each phase.

The device provides the possibility of adjusting the parameters (voltage threshold, time of automatic reclosing and time delay of protection operation), selection of the voltage of the monitored mains (400 V or 415 V) and a set of protective functions. After restoring the voltage parameters of the mains, the device enables again the load after the reclosing time.

RNPP-302M numeric voltage monitoring relay is designed for protection of three phase loads against major type of mains faults, as:

• RMS voltage reaching beyond admissible thresholds – over and under voltage
• Phase loss or Single phasing
• Phase sequence order violation or reverse phase sequence
• Phase coincidence or shorting of two or more phases
• Phase Imbalance or asymmetry
• Contactor output side monitoring – full phase switching, contactor health

The device performs monitoring the main circuit parameters and de-energizes (trips) load when the parameters fall beyond specified boundaries.

RNPP-301 voltage monitoring relay is designed for protection of three-phase loads against major type of mains faults, as:

• RMS voltage reaching beyond admissible thresholds
• Phase sequence order violation and phase coincidence
• Violation of the mains voltage phase completeness and symmetry

The device performs monitoring the main circuit parameters and de-energizes load when the parameters fall beyond specified boundaries. The relay also tracks the status of magnetic starter power contacts at no-load and under load while monitoring their operability (burning or sticking).