Compact, reliable EV MCU testing: how Stäubli’s CombiTac secured long-life automatic aging lines

As part of the growing industry in electric vehicles, our customer develops and produces sophisticated motor control units (MCUs) that must be thoroughly validated before final delivery to customers series production. 

To ensure that every MCU meets stringent functional safety and performance standards, the customer operates automatic aging lines where units are exposed to prolonged high-current loads and real-world operating conditions. In these highly automated environments, the connectivity between the MCU and the test bench is mission-critical: connectors must ensure safe, stable power and signal transmission, support high test throughput and withstand intensive daily usage over many years. For engineering and operations leaders, the test connector is not a minor component, but a key enabler of predictable, high-quality EV production.

When high current meets limited space

For a new generation of automatic aging lines for EV motor control units, the customer faced a demanding combination of requirements. The modular connector combines power, signal and data in a very compact space defined by the test station design. At the same time, the connector is designed for intensive operation in the range of 100.000 mating cycles.

The project team faced clear design requirements: prevent contact heating and performance drifting over time, ensure stable measurement signals and operator safety, and stay within a tight budget. Because standard, non-modular connectors couldn’t deliver the right balance of current capacity, robustness, compactness, and total cost of ownership, the customers decision-makers set out to identify a connectivity solution that would meet rigorous technical requirements and support the economics of the new test lines.

One connector, maximum performance 

The customer selected the modular CombiTac system as the connectivity backbone for the automatic aging lines. In the final configuration, each connector integrates 5 power contacts and 60 signal contacts in a compact interface, delivering both high-current power and sensitive signal transmission in one solution. 

CombiTac’s robust, long-life design ensures that the connectors can withstand up to 100.000 mating cycles with low contact resistance and minimal heating, even under sustained high-current loads. This directly supports the intensive operating profile of the aging lines. The modularity of CombiTac also enabled customers engineering team to tailor the exact mix of power and signal contacts required, without compromising on system layout or test density. 

Lower TCO through long life connectivity

With Stäubli’s CombiTac solution, our customer implemented compact, high‑performance automatic aging lines for its MCUs. The long‑life connector design reduces maintenance and downtime by ensuring stable contact resistance and low heat generation across up to 100,000 mating cycles. This supports continuous operation, predictable service planning, and a lower total cost of ownership for the connectivity system.

Reliable power and signal transmission also improve measurement accuracy and consistency throughout each validation run. This strengthens confidence in the test process, reduces rework, and supports the safe, dependable deployment of EV components. The project highlights how well‑chosen connector technology can significantly enhance both technical robustness and operational efficiency in high‑volume EV testing.

Beyond the hardware, the project benefited from Stäubli’s established reputation and partnership with the customer. Local technical experts provided application support during the design phase, helped optimize the connector configuration and responded quickly to questions or adjustments. Altogether, the customer gained not only a connector, but a reliable, service-backed solution that fit seamlessly into its EV testing strategy.