MCB Accessories for TDM5 (AL5, AU5, SH5, UV5)

Product Introduction

1. AL - Alarm Contact
Function: A mechanical, non-powered signal contact. It changes state only when the breaker trips automatically due to overload or short circuit.
Purpose: Provides a remote signal for fault tripping, used for alarms and fault identification. It does not operate during manual switching.
Key Feature: Requires no external power supply; it outputs a signal through the mechanical movement of the microswitch.

2. AU - Auxiliary Contact
Function: A mechanical, non-powered signal contact. It real-time reflects the mechanical position (ON or OFF) of the breaker's main contacts.
Purpose: Used for remote status monitoring. Its state changes whenever the breaker is operated manually or tripped on a fault.
Difference from AL: AU indicates position, AL only signals a fault trip.

3. SH - Shunt Release
Function: This is an electromagnetic tripping module that requires an external control signal. When its coil receives a rated voltage signal (e.g., 220V AC/DC), it activates immediately to trip the breaker.
Purpose: Used for remote electrical opening. Common in applications like fire alarm linkage, emergency stop systems, and Building Automation Systems (BAS) where remote power shutdown is required.
Key Feature: It must be wired and requires a power signal to operate. Its trigger condition is the opposite of the Under-Voltage Release (UV).

4. UV - Under-Voltage Release
Function: This is an electromagnetic tripping module that requires a continuous power supply. It trips the breaker when the voltage across its coil drops below a set value (e.g., below 70% Un) or is lost completely.
Purpose: Used to protect equipment from operating under low voltage conditions or to provide loss-of-power protection, preventing equipment from unexpectedly restarting when power returns.
Key Feature: Requires continuous wiring. The coil is energized under normal operation; it trips upon loss of voltage.

Technical Data