Draw-out circuit breaker with sentinel trip unit 66 kA 400 A 4P HW1E404DB

Draw‑out air circuit breaker with sentinel trip unit – construction and mounting

The device is a draw‑out air circuit breaker with four poles, designed for installation in distribution cabinets where quick and safe load disconnection is required. It is not mounted on a DIN rail – its connection is made via a separate enclosure part, allowing easy replacement without disconnecting wires from the rail. The draw‑out design simplifies service and inspection while providing voltage isolation when working near the equipment.

All main and auxiliary contacts are linked to the enclosure by a modular component, eliminating the risk of wiring errors during assembly. An optional motor drive can be added to the unit, enabling remote operation – useful in automation systems or where access to the breaker is limited.

Protection and status indicators

The breaker does not include built‑in ground‑fault or under‑voltage release protection – its operation relies solely on the sentinel trip mechanism, which responds to overloads and short circuits. The rated short‑circuit making capacity is 66 kA at 400 V, meaning the device can safely interrupt very high fault currents typical of industrial installations.

A notable feature is the trip indicator – it provides a quick visual check of the breaker’s status without opening the enclosure. Additionally, the breaker is equipped with four auxiliary changeover contacts, which can be used for status signalling (e.g., “on”/“off”) or integration with automation systems – such as alarm control or data logging.

Compliance and operating conditions

The device meets the EU CE compliance directive and is intended for use in networks with a rated voltage from 440 V to 690 V. The IP2X protection rating offers basic protection against accidental contact with live parts but does not protect against dust or water, so installation should be performed in closed, dry distribution cabinets.

It contains no breaking contacts nor make‑before‑break auxiliary contacts – its function is focused on the main making and status indication. The lack of TH‑rail mounting capability means it must be mounted directly to the cabinet frame, requiring appropriate preparation of the mounting location.