土方机械.使用电力驱动器和相关部件和系统的机械的电气安全.第2部分：外部动力机械的特殊要求

[中文适用范围]： 本文件规定了外部供电（连接电源，包括由外部专用发电机供电的机器）、电动土方机械（EMM）中的电气设备及其组件的特定安全要求。 它适用于在任何频率下使用 50 V–36 kV AC rms 范围内的板载电压和 75 V–36 kV DC（包括脉动 DC 的任何重复率）的室外使用的机器。 设备内发生的电压不被视为板载电压，因此不在其范围内。 它旨在与 ISO 14990-1 结合使用，该标准给出了 EMM 的一般要求，无论其供电方式如何。 给出了自供电机器的特定要求（例如，具有供电功能的内置充电器的电池供电机器），在这种情况下 [外文原描述]： ISO 14990-2:2016 the particular safety requirements for the electrical equipment and its components incorporated in externally-powered (mains-connected, including machines powered by external dedicated generators), electrically-driven earth-moving machines (EMMs). It is applicable to those machines using on-board voltages in the range of 50 V?36 kV AC r.m.s. at any frequency and 75 V?36 kV DC ? including any repetition rate of pulsating DC ? intended for outdoor use. Voltages occurring within devices are not considered to be on-board voltages and are thus not within its scope. It is intended to be used in conjunction with ISO 14990‑1, which gives general requirements for EMMs regardless of how they are powered. Requirements specific to self-powered machines are given in ISO 14990‑3. However, it is possible for an EMM to be both self-powered and externally-powered (e.g. a battery-powered machine having a built-in charger with power supply function), in which case ISO 14990‑3 is also applicable.