Modular Three-Phase Phase Monitoring | Sequence | Protection Relay | 3x380V | Phase Asymmetry 30% | DIN

The device is designed for 3x380V AC three-phase systems. Integrated fixed 30% phase asymmetry monitoring helps protect equipment against dangerous phase imbalance, while phase sequence monitoring prevents the relay output from being activated if phases L1, L2, and L3 are connected in the wrong sequence. The device is particularly suitable for monitoring the rotation direction and supply condition of three-phase motors.

The device has fixed 30% phase asymmetry protection. When the voltage deviation of one or more phases exceeds the permitted threshold, the device detects the fault and deactivates the relay output. In this case, the ERR LED indicator flashes approximately every 2 seconds, while the OUT indicator switches off.

The relay checks the L1-L2-L3 phase sequence. If the phase sequence is incorrect, the relay output is not activated. This protection is especially important for three-phase electric motors, pumps, compressors, and other equipment where an incorrect phase sequence can reverse the direction of rotation and cause mechanical or process-related faults.

• Integrated three-phase network monitoring.
• Fixed 30% phase asymmetry protection.
• Phase sequence monitoring helps prevent incorrect rotation direction of three-phase motors.
• Clear ERR and OUT LED indication allows quick identification of the device status.
• Low energy consumption – operating power below 6VA.
• Standard DIN rail mounting allows easy integration of the relay into control and automation panels.
• Changeover relay contact suitable for controlling contactors and other control circuits.
• Compact and lightweight housing suitable for control cabinets with limited space.

• Fixed asymmetry threshold: the 30% phase imbalance threshold is not adjustable.
• Neutral conductor required: this version is designed for a 3x380V AC + N electrical system.
• Limited relay contact load: the output contact is rated for up to 5A / 250V AC resistive load. A contactor must be used for higher loads.
• Not suitable for humid environments: the device must be installed in a dry environment or in a suitably protected electrical enclosure.

In a production line, a three-phase 380V AC electric motor is controlled through a contactor. This phase monitoring relay is installed in the control panel. When the L1, L2, and L3 phase voltages are normal, phase asymmetry does not exceed 30%, and the phase sequence is correct, the relay OUT indicator lights up and the contactor control circuit can remain active. If one of the phases deviates significantly or the phase sequence changes, the relay output is deactivated and the contactor disconnects the motor. This reduces the risk of three-phase motor failure or incorrect rotation direction.

The relay is designed for a three-phase 3x380V AC electrical network with neutral connection and operates at a frequency of 50/60Hz.

Yes. The device has a fixed 30% phase asymmetry protection threshold.

No. The phase asymmetry protection threshold of this relay is fixed at 30%.

Yes. If the L1-L2-L3 phase sequence is incorrect, the relay output is not activated and the ERR LED indicator signals a fault.

A flashing ERR LED at approximately 2-second intervals indicates a phase asymmetry fault.

A continuously lit ERR indicator indicates an incorrect phase sequence.

The relay contact is rated for up to 5A / 250V AC resistive load, therefore for three-phase motors it is recommended to use the relay output to control the contactor coil rather than switching the motor directly.

Use the device only according to its intended purpose and wiring diagram. Do not use it in a humid environment. Provide a separate switch and automatic circuit breaker in the installation circuit. They must be installed near the device, in a location easily accessible to the operator, and marked as electrical circuit disconnecting means. Disconnect the electrical power supply before installation or maintenance work.

Disconnect the device from the electrical power supply before carrying out maintenance work. Clean the housing with a dry, soft cloth. Do not use conductive materials, aggressive chemical cleaners, or solvents that may damage the device. After cleaning, check that the relay operates correctly.