Sensata Technologies has introduced the FaultBreak™ contactor, a high-voltage switching and protection device engineered for electric vehicle power systems. The component combines fuse and contactor functions in a single unit, targeting reduced system complexity, lower weight, and improved fault clearance performance.
Highlights
- FaultBreak is validated for repeated fault clearing at 16 kA and 1 kV, targeting full battery short circuit conditions
- The passive fuse function operates without external detection electronics, supporting ISO 26262 compliance
- Component count is reduced by more than 50% compared to conventional contactor and fuse systems
- Unlike pyrofuses, FaultBreak is resettable after recoverable fault events, reducing vehicle downtime and warranty costs
Addressing a Core EV Architecture Challenge
Reliable fault management is increasingly critical as EV platforms move toward higher voltage architectures. Automakers need protection devices that respond quickly to high-magnitude fault events. Traditional solutions — pyrofuses, busbars, and separate contactors — add weight, cost, and integration complexity.
Sensata’s FaultBreak consolidates these functions into one device. By eliminating separate fuse elements and associated low voltage harnesses, the solution simplifies the overall power architecture. Low contact resistance also limits power loss during normal operation.
Passive and Resettable Fault Protection
A key differentiator is the FaultBreak’s passive fuse functionality. The device interrupts fault currents without relying on external detection electronics. This approach reduces failure modes and supports functional safety targets under ISO 26262.
Additionally, the resettable design allows the system to recover from temporary or nuisance faults without component replacement. This is a significant operational advantage over single-use fuse technologies, which require physical intervention after each fault event.
Dual Configuration Option
For applications requiring higher reliability targets, two FaultBreak units can be paired in a dual configuration. This creates system-level redundancy and supports more demanding safety requirements.
Performance and Integration Specifications
FaultBreak’s hermetic sealing delivers stable, low contact resistance across operating conditions. Its compact footprint requires no additional cooling equipment. Key performance attributes include:
- Fault clearing capacity: Validated at 16 kA @ 1 kV, repeated breaks
- Passive fuse function: No external electronics required
- Resettability: System recovery after recoverable fault events
- Component reduction: Over 50% fewer components vs. traditional fuse-contactor systems
- Compliance support: Designed to support ISO 26262 requirements
Markus Schwabe, EVP of Automotive at Sensata Technologies, said the FaultBreak contactor “helps our customers build electric vehicles that are safer, more dependable, and more economical to produce and maintain.”
Availability and Events
More information on the FaultBreak contactor is available at www2.sensata.com/FaultBreak-Series. Sensata is also hosting a webinar covering high voltage fault management strategies at www2.sensata.com/FaultBreak-webinar.
The company will feature FaultBreak at ACT Expo 2026, May 4–7 in Las Vegas, at booth 2017.
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