Circuit breaker series protects equipment and prevents down-time

The DWB moulded case circuit breakers are designed with rated operating voltages up to 690V AC or 250V DC and are available in three-pole and four-pole versions in six case sizes with rated operating currents from 16-1,600A. The circuit breakers and associated equipment and components can be switched on and off remotely with related accessories.

The whole range features the same accessories including auxiliary switch blocks, undervoltage and shunt opening releases, and phase separators so engineers can reduce the required diversity of parts stock. That has a positive impact on stock management, type selection and detail engineering.

The modular design of the DWB series allows the complexity of the circuit breakers to be adapted to the requirements of each application. For example, the needs of simple cost-sensitive applications can be met using circuit breakers with fixed overload and short-circuit tripping mechanisms based on the thermal-magnetic operating principle.

By contrast, circuit breakers with adjustable overload and short-circuit tripping mechanisms can be deployed in more sophisticated solutions. Circuit breakers with adjustable current-dependent or time-delayed overload and short-circuit tripping using electronic tripping mechanisms are available to meet complex requirements.

These versions can be used to construct selective protection networks to ensure that only the circuit breaker directly ahead of the fault location is tripped and all other parts of the network are reliably supplied with power.

Four-pole circuit breakers are available with and without neutral conductor protection. Versions without overload tripping can be used to protect non-inductive loads and they are also used in starter combinations, with the circuit breaker providing short-circuit protection and a separate overload relay providing overload protection. Electronic overload relays with a wide variety of protective effects are also frequently used in this connection.

Additionally, power disconnectors are available for effective interruption of power circuits. The state-of-the-art circuit breakers in the DWB series are manufactured and tested in accordance with the IEC/EN 60947 standard (DIN VDE 0660).