Tehonkesto

Tehonkesto is a Finnish term that denotes the capacity of a device to sustain a specified power output over a defined period. It combines teho (power) and kesto (endurance or duration) and is used in engineering, procurement, and consumer product descriptions to convey endurance under thermal and load conditions. Unlike peak or momentary power ratings, tehonkesto refers to sustained operation within safe temperature and reliability margins.

In practice, tehonkesto is defined by test conditions such as ambient temperature, cooling method, duty cycle, and measurement endpoints (temperature rise, degradation of performance, or failure). Because standards and definitions vary by manufacturer and sector, the exact numerical rating is not universally uniform; it is typically specified in accompanying documentation with the testing protocol.

Applications include internal combustion engines, electric motors, power supplies, turbines, and energy storage systems, where sustained load handling is critical. It is used by engineers to compare equipment and by marketers to describe product robustness, though users should interpret ratings by referencing the stated test conditions.

Limitations: tehonkesto does not by itself guarantee long-term reliability; it reflects performance during a defined test window. Users seeking comparable assessments should compare under identical test parameters.

See also: continuous power rating, thermal design, duty cycle, reliability testing.