Nopeusrajoitinjärjestelmä

Nopeusrajoitinjärjestelmä, or speed limiter system, is a vehicle safety feature designed to prevent a vehicle from exceeding a predetermined maximum speed. It is a mandatory component in many commercial vehicles, such as trucks and buses, in various countries to enhance road safety and enforce traffic regulations. The system typically operates by electronically limiting the engine's power output or fuel supply when the set speed limit is reached.

The primary purpose of a speed limiter is to reduce the risk of accidents caused by excessive speed. By capping the vehicle's maximum velocity, it helps drivers maintain control, especially in adverse weather conditions or on slippery roads. It also contributes to more predictable traffic flow and can reduce fuel consumption. The implementation and specific speed limits are often dictated by national or regional legislation, with different regulations applying to different types of vehicles and their intended use.

Modern speed limiter systems are integrated with the vehicle's engine control unit (ECU). They can be factory-fitted or retrofitted, and their settings are often sealed or protected to prevent tampering. Regular checks and calibration are usually required to ensure the system functions correctly and complies with legal standards. The presence and operational status of a speed limiter are often subject to vehicle inspections.