Modular Voltage | Phase Sequence Monitoring | Protection Relay | 3x380V | 260-360V | 400-460V | DIN

The device allows the undervoltage protection threshold to be set from 260V to 360V AC and the overvoltage protection threshold from 400V to 460V AC. The trip delay is adjustable from 0.1 to 10 seconds. The relay also monitors the phase sequence and prevents the output from being activated if the phases are connected in the wrong sequence. Once the fault is cleared, the device automatically restores operation.

The device additionally monitors the phase sequence of the three-phase network. If phases L1, L2, and L3 are connected in the wrong sequence, the relay output is not activated. This function is particularly important for three-phase electric motors, pumps, compressors, and other equipment whose direction of rotation depends on the phase sequence.

When the monitored voltage is between the set U< and U> thresholds, the relay output remains active. If the voltage moves outside the set limits, the device begins counting the configured delay time. If the fault remains until the end of the delay, the relay switches off. Once the mains voltage returns to normal, the device automatically returns to the operating state.

• Monitors both undervoltage and overvoltage in a three-phase network with a single device.
• Integrated phase sequence monitoring helps protect three-phase motors against incorrect rotation direction.
• Adjustable undervoltage protection threshold from 260V to 360V AC.
• Adjustable overvoltage protection threshold from 400V to 460V AC.
• Adjustable 0.1 – 10 second delay reduces the likelihood of unnecessary trips caused by short-term mains fluctuations.
• Automatic reset once the mains fault has been cleared.
• 1-SPDT changeover relay contact provides flexible integration into contactor and automation control circuits.
• Standard 35mm DIN rail mounting in control and distribution panels.

• Neutral conductor required: the device is designed for a 3x380V AC network with neutral connection.
• Limited relay contact load: the output contact is rated for up to 5A / 250V AC resistive load, therefore a contactor must be used to control higher-power loads.
• Not suitable for humid environments: the device must not be operated in locations where it is directly exposed to moisture or water.
• Incorrect phase sequence blocks the relay: the output will not be activated until the phases are connected in the correct sequence.

In an industrial system, a three-phase electric motor is controlled through a contactor. This voltage and phase sequence control relay is installed in the control panel. For example, the undervoltage threshold is set to 330V, the overvoltage threshold to 430V, and the trip delay to 2 seconds. When the mains voltage is within the configured range and the L1-L2-L3 phase sequence is correct, the relay activates the contactor control circuit and the motor can operate. If the voltage drops below 330V, rises above 430V, or the phase sequence changes, the relay output switches off and the contactor disconnects the motor. Once the mains parameters return to normal, the relay automatically restores operation.

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

Yes. The U< protection threshold can be adjusted from 260V to 360V AC.

Yes. The U> protection threshold can be adjusted from 400V to 460V AC.

Yes. If the L1, L2, and L3 phase sequence is incorrect, the relay output is not activated.

Yes. The trip delay can be adjusted from 0.1 to 10 seconds.

No. The device has an automatic reset function and automatically restores relay operation once the mains parameters return to the permitted range.

The relay output contact is rated for up to 5A / 250V AC resistive load. For three-phase motors and other higher-power loads, it is recommended to use the relay output to control the contactor coil.

Use the device 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 the means for disconnecting the device from the electrical circuit.

Before performing maintenance or cleaning, switch off the device power supply and disconnect it from the electrical circuit. Clean the housing with a soft cloth. Do not use conductive materials or chemical cleaners that may damage the housing or electronic components. After cleaning, make sure that the device operates correctly.