Siemens Expands Series of 3WA Power Circuit Breakers for Next-Gen Electrical Distribution 

Siemens has launched two new versions of its Sentron 3WA Power Circuit Breakers, alternatively known as Air Circuit Breakers (ACBs). Series 3WA3 meets the requirements of UL 1066 and IEC 60947-2 standards, which enables customers to use it worldwide. This is particularly advantageous for switchgear manufacturers and OEMs producing systems for both standardization areas – IEC and UL.

The 3WA2 series is designed exclusively for the UL 489 market. The two new ACB model series complement the 3WA1 version for IEC markets, which had been launched in the fall of 2020.

Siemens offers a full range of ACBs which are based on a consistent system and offer great flexibility for applications around the globe. The Sentron 3WA Power Circuit Breakers are part of the Siemens Xcelerator portfolio. Siemens Xcelerator is an open digital business platform that enables customers to accelerate their digital transformation easier, faster, and at scale. 

 As a core element of low-voltage switchboards, ACBs reliably protect electrical installations in buildings, infrastructure and industrial facilities from damage caused by short circuits, ground faults or overload faults. This is essential also for critical infrastructure, such as hospitals or data centers. The Sentron 3WA circuit breaker follows the Siemens tradition of high reliability ACBs that are built to perform over the lifetime of a facility. At the same time, the Sentron 3WA circuit breakers support software-based planning and engineering, digital testing and monitoring, and seamless integration in automation and IoT systems. Upgrades can be completed 100 percent digitally. Users simply download new features from the Internet and add them using an app. 

When technological requirements change, it is easy to add new features to the electronic trip unit (ETU600) installed in the Sentron 3WA air circuit breakers using the Sentron “powerconfig” commissioning software and a USB or communication port. The features are available online and are continually expanded by Siemens. Users benefit from high investment protection. For applications without a need for measuring functions or scaling options, the Sentron 3WA ACBs can now also be configured with an ETU300 for easy standard protection.  

The Sentron 3WA ACB trip units also have more standard features, such as the integrated arc energy reduction feature (Dynamic Arc Flash Sentry, DAS+), which ensures that Sentron 3WA ACBs trip more rapidly in the event of a fault during work being carried out in the immediate vicinity of live parts. In this way, the arc energy and thus the energy released in the power distribution equipment room is reduced. This technology complies with the National Electric Code (NEC) for the US market; it is designed to protect service technicians from serious injury resulting from arc flash hazards. 

The Sentron 3WA ACB UL series 3WA2 and 3WA3 are available in three frame sizes with rated current ranges from 800 to 5,000 A.