Alstom Launches its 145kV/63kA Dead Tank Circuit Breaker without TRV capacitors

The dead tank circuit breaker model DT1-145 63 will serve ratings up to 145 kV for short circuit currents up to 63 kA and continuous currents up to 4000A.

Charleroi, (PA) - Alstom, a leading power generation, transmission and rail infrastructure technology provider, recently announced the launch of a high-voltage, high-performance 145kV dead-tank circuit breaker, serving ratings from 72,5kV up to 145kV for power transmission systems. The circuit breaker uses a spring-spring operating mechanism and is fully tested to perform at 63kA without TRV capacitors.

By eliminating the need for capacitors, the DT1-145 63 avoids technical issues and challenges associated with the installation of additional line-to-ground capacitors at a substation, such as creation of transient currents and voltages generated during switching operations and their effect on substation equipment, the creation of surges coupling into control circuits and the introduction of ground transients. When required, the line-to-ground capacitors are used to alter the transient recovery voltage on one or both sides of the circuit breaker in order to allow successful interruption of a fault current by modifying the delay time and rise time of the transient voltage appearing across the circuit breaker contacts after current interruption. Alstoms interrupter designs provide for capacitor-free performance without compromising on performance and value.

Built in Alstoms dead tank circuit breaker center of excellence in Charleroi, Pennsylvania, the DT1-145 63 represents an evolutionary step forward as Alstom expands on its highly successful DT series of circuit breakers, which already have over 25,000 in service worldwide.  The new model joins the existing lineup of dead tank circuit breakers from 38kV to 550kV and like all Alstom designs is fully tested to the latest IEEE standards including general and definite purpose ratings. 

To bring this compact yet high-performance breaker to life, a multi-national joint development team worked together on developing a product for maximum performance while optimizing the design using Alstoms FK3 family of spring-spring operating mechanisms. There are over 180,000 FK3s in service worldwide. The spring-spring mechanism FK3-4 is extensively tested to 10,000 operations and the class M2 certification is ensuring trouble-free operation throughout the life time of the circuit breaker. Thanks to the low-energy mechanism and lifetime lubricants the circuit breaker is virtually maintenance free. The installation on-site requires only few simple steps and no special tools.

Each breaker is factory tested using Alstoms proprietary gas tightness testing systems which provides the industrys only measurable, quantifiable test results on the dead tank circuit breakers in fully assembled as-shipped condition. Alstom leads the industry in SF6 gas tightness testing technology including seals, casting and plumbing system.

To learn more, download a brochure.