This document applies to all electronic equipment for control, regulation, protection, diagnostic, energy supply, etc. installed on rail vehicles. For the purpose of this document, electronic equipment is defined as equipment mainly composed of semiconductor devices and recognized associated components. These components are mainly mounted on printed circuit boards. Sensors (e.g. current, voltage, speed) and semiconductor drive units for power electronic devices are covered by this standard. Complete semiconductor drive units and power converters are covered by EN 61287-1. This document covers the conditions of operation, design requirements, documentation, and testing of electronic equipment, as well as basic hardware and software requirements considered necessary for compliant and reliable equipment. Specific requirements related to practices necessary to ensure defined levels of functional safety will be determined in accordance with relevant railway safety standards. The software requirements for on-board railway equipment are specified by EN 50657.