Auxiliary side contact 1NO + 1NC for MPX3 417400

Circuit Status Signaling Without Interference with the Main Circuit

This auxiliary module enables remote monitoring of the main contact positions in MPX³ series motor circuit breakers. It allows the installer or system operator to easily verify whether the circuit is currently energized or de-energized without the need to physically open the device enclosure. This is crucial in applications requiring automation or remote diagnostics of the installation status.

The device construction is designed for side mounting, meaning it does not occupy additional space above the circuit breaker (as is the case with top mounting), but only extends its width. Such an arrangement is particularly useful in distribution cabinets with limited height or where other components are located above the circuit breaker. The module features a 1NO + 1NC configuration, providing full flexibility in connecting signaling:

• Normally Open contact (NO) closes the signaling circuit when the circuit breaker is energized (e.g., lighting up a "Running" LED).

• Normally Closed contact (NC) opens the circuit upon energization (e.g., extinguishing a "Fault" LED or changing the state of a PLC controller input).

Application and Operating Conditions

The device is dedicated exclusively for use with Legrand MPX³ series motor circuit breakers. It must not be used with other series or as a universal component for any switching apparatus. The rated current for AC-15 applications at 230 V is 3 A, which is sufficient to power standard light indicators, auxiliary relays, or low-power logic controller inputs.

To ensure safety and durability of electrical connections, screw terminals have been used. This solution allows for secure tightening of conductors with cross-sections corresponding to the standards for this type of equipment, eliminating the risk of contact loosening due to vibrations characteristic of industrial installations. Mounting is performed directly on the side wall of the main circuit breaker, simplifying the process of expanding existing installations – there is no need to replace the entire apparatus with a version featuring built-in signaling.

Key Construction Features and Capabilities

It is important to note that this module does not have its own power supply – it operates as a mechanical switch controlled by the movement of the main circuit breaker mechanism. Its function is solely to physically open or close the control circuit in accordance with the position of the MPX³ circuit breaker lever. Thanks to its simple construction and absence of electronic components, the device exhibits high reliability and resistance to environmental conditions typical of electrical distribution boards.

In practice, this means the device offers one normally open contact and one normally closed contact, completely omitting switching functions. The entire assembly is mounted on the side of the main apparatus, which is a dedicated solution for the MPX³ series. The control circuit can operate with a current up to 3 A in category AC-15 at 230 V, and connections are made via proven screw terminals, ensuring durable conductor fixation even under severe vibration conditions.