Relpol RPB-2ZSMI-UNI Bistable Sequential Relay 2NO 16A 12-240V AC/DC with Memory

The Relpol RPB-2ZSMI-UNI is a high-performance bistable sequential relay designed for precise electrical control in industrial and building automation environments. Featuring two normally open (2NO) contacts with a 16A rating, this device provides reliable switching for various loads. Its universal power supply compatibility, ranging from 12V to 240V AC/DC, allows for seamless integration into diverse electrical systems without the need for multiple relay variants. The integrated memory function ensures that the relay maintains its last state even after a power interruption, providing consistent operation in critical applications.

Advantages

This relay stands out due to its robust construction and ability to handle high inrush currents of up to 80A for 20 milliseconds, making it suitable for demanding lighting and motor control tasks. The bistable mechanism ensures energy efficiency, as the coil does not require continuous power to maintain the contact position. Its compact design facilitates easy installation in standard distribution boards, while the wide voltage range simplifies inventory management and system design by offering a single solution for various voltage levels.

Suitable for

• Lighting control systems in commercial buildings
• Sequential switching of industrial machinery
• Automation of electrical circuits requiring state retention
• Energy management systems

When it may not be suitable

This relay is not intended for applications requiring high-frequency switching beyond its mechanical and electrical life ratings. It is also not suitable for environments where the ambient temperature or humidity levels exceed the manufacturer's specified operating limits.

Key specifications

• Contact configuration: 2NO (Normally Open)
• Rated current: 16A
• Supply voltage: 12-240V AC/DC
• Inrush current capacity: 80A (20 ms)
• Function: Bistable sequential with memory

How to use

The relay should be installed by a qualified professional in accordance with local electrical regulations. It is designed for mounting on standard DIN rails within an enclosure. Connect the control signal to the designated input terminals and the load to the 2NO contact terminals. Ensure that the supply voltage matches the specified range before energizing the device. The sequential operation is triggered by pulses applied to the control input, which toggles the relay state according to the internal logic.

What to consider before purchase

• Verify that the total load current does not exceed the 16A rating
• Ensure the control signal voltage is compatible with the 12-240V AC/DC range
• Check available space in the distribution cabinet for DIN rail mounting
• Confirm that the application requirements align with the sequential switching logic

Usage recommendations

For optimal performance and longevity, ensure that the relay is protected against short circuits using appropriate fuses or circuit breakers. Regularly inspect the terminal connections to ensure they remain tight and free from oxidation.