SENTRON 3QD2 semiconductor circuit breaker (SCCB)

Configuring the SCCB with SENTRON Powerconfig

Using the free commissioning and parameterization software SENTRON Powerconfig, you can individually set parameters for the following DC protection functions on the SENTRON 3QD2 DC circuit breaker: Rated current/voltage, overload protection, short-circuit protection ST, instantaneous short-circuit protection INST, under-/overvoltage protection, and pre-charging (on/off).

In addition, the alarm and error responses as well as the digital inputs and outputs of the DC circuit breaker can be configured for the respective application.

Fully electronic protection instead of electromechanical switching

DC-based applications place high demands on protection technology. Typical challenges include high inrush currents, fault arcs that are difficult to extinguish, slow interruption due to mechanical inertia, and limited system transparency. These factors can lead to significant secondary damage, reduced availability, and increased risk for equipment and service personnel.

The physical operating principles of conventional electromechanical switching and protection devices limit switching speed, arc handling capability, and the ability to provide detailed system data. As a result, they cannot effectively address the dynamic behavior and protection needs of advanced DC applications.

The semiconductor-based SENTRON 3QD2 DC circuit breaker overcomes these limitations through fully electronic operation. It detects faults in real time and clears them within microseconds to nanoseconds, significantly limiting fault currents and reducing potential damage to cables, components, and energy sources. The absence of mechanical contacts eliminates arcing, increasing service life and reliability. In addition, integrated measurement and communication functions provide full transparency and enable predictive maintenance.

Many features instead of many devices

Modern DC applications require a wide range of protection, switching, and control functions to ensure safe and reliable operation. Today, these functions are typically implemented using multiple separate components, including protective devices, load switches, communication modules, monitoring systems, and remote-control units. This increases system complexity, space requirements, and wiring effort, along with the associated costs. In addition, system transparency is often limited. At the same time, the risk of failure increases due to the large number of interfaces, while response times are reduced.

The SENTRON 3QD2 DC circuit breaker combines multiple functions into a single solution, significantly reducing complexity, cost, and space requirements:

• Protection: Ultra-fast fault detection and interruption in case of short circuits, overcurrent, or other faults – fully electronic and arc-free
• Switching: Solid-state load switching with long service life and precise control
• Communication: Integration into higher-level systems via digital interfaces such as Modbus TCP or PROFINET
• Disconnection & isolation: Personnel safety through secure galvanic isolation during maintenance or fault conditions
• Real-time load and energy monitoring: Continuous monitoring of current, voltage, and energy flows
• Remote control and diagnostics: Maximum flexibility and minimal downtime

Standard-compliant protection coordination according to IEC 60947-10

The semiconductor-based SENTRON 3QD2 DC circuit breaker complies with the requirements of EN IEC 60947-10 and supports standard-compliant coordination in modern protection concepts for low-voltage systems.

More flexibility instead of rigid device architecture

DC applications require a wide range of protection and control functions. However, conventional devices are typically rigid, designed for a single specific function, and can only be used effectively in combination with other components. This results in high engineering effort, limited flexibility, complex integration, reduced transparency, and increased space requirements.

The configurable SENTRON 3QD2 DC circuit breaker combines protection, switching, isolation, communication, as well as energy and load monitoring in a single system. Freely adjustable protection parameters – incl. current, voltage, temperature, time delays, and selectivity – together with modularly activatable functions, enable precise adaptation to the specific application, both during commissioning and operation.