In this article, the authors discuss the crucial aspects of the insulation resistance testing of photovoltaic (PV) installations. This test verifies the integrity of the wiring systems and can be used to detect or prevent damages to wiring as well as ground faults. The insulation resistance test measures the resistance between the ungrounded circuits and the ground under the application of high voltage. The baseline insulation resistance can be compared to measurements over time to assess the degradation of PV arrays or conductors. This test is accepted worldwide as a crucial element of commissioning and acceptance, and it is governed by several technical standards.

中文翻译：

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大功率并网光伏装置的绝缘电阻和故障：案例研究

在本文中，作者讨论了光伏（PV）装置的绝缘电阻测试的关键方面。该测试可验证布线系统的完整性，可用于检测或防止布线损坏以及接地故障。绝缘电阻测试是在高压下测量未接地电路与地面之间的电阻。可以将基线绝缘电阻与随时间变化的测量结果进行比较，以评估PV阵列或导体的退化。该测试已被全世界接受为调试和验收的关键要素，并受多项技术标准的约束。