Voltage release 200-250V AC/DC (SH) HWX023H

Operates as a pulse-operated trip unit

This is not a relay or a contact-based component – it is a control coil that activates the tripping mechanism in a circuit breaker or motor circuit breaker. Simply apply 200–250 V AC or DC voltage to trigger the release and open the circuit. No additional control wiring or complex circuits are required – it connects directly to the circuit breaker terminals.

Requires only a short pulse but operates continuously

Voltage does not need to be maintained continuously. A pulse lasting at least 100 ms is sufficient – after this, the breaker opens and the coil remains de-energized. However, it can be connected for continuous operation: it consumes only 5 VA in holding mode, ensuring low load on the installation and no risk of overheating. At startup, it draws 200 VA – which is normal for such coils and does not affect grid stability, as this lasts only milliseconds.

Operates under extreme conditions

It can be installed where temperatures drop below -25 °C or rise up to 70 °C without loss of functionality. Overvoltage resistance (6 kV) and insulation rated for 480 V ensure safety even during sudden voltage fluctuations. IP4X rating guarantees protection against solid objects larger than 1 mm – meaning dust, fine particles, or small fragments do not interfere with operation.

Compatible with multiple breaker types

It works with HW1, HW2, HW4, HW6 type circuit breakers, motor circuit breakers, and cam switches. It is not compatible with overload relays – that is not its function. Its sole role is to initiate the tripping mechanism at the appropriate moment. A second coil (SH2) can be installed, but in that case, an undervoltage release (UV) cannot be added – this is a key configuration limitation.

Simple installation, but requires attention

There are no contacts to connect – only two terminals for the coil. Everything depends on correct connection to the control circuit. As emphasized in Hager's installation instructions: pulses must be longer than 100 ms and must not be interrupted during operation. If you intend to use two coils, remember that the second one blocks the possibility of installing a UV release.