IEC 61557-15:20 14规定了与功能安全相关的要求，并基于IEC 61508标准系列，用于实现IEC 61557-8中规定的绝缘监测设备（IMD）和根据IEC 61557-9的绝缘故障定位系统（IFLS），根据IEC 61508-1生命周期的阶段10。这些设备为IT系统提供安全相关功能。IEC 61557的这一部分是 -仅涉及旨在降低IMD和IFLS使用过程中的功能风险的功能安全要求； -仅限于器械本身或系统中多个IMD或IFLS一起工作直接产生的风险；和 -旨在定义器械提供的基本安全功能。IEC 61557的这一部分没有 -根据IEC 61010处理电气安全-1以及IEC 61557-8和IEC 61557-9的要求； -涵盖IMD或IFLS特定用途的危害和风险分析； -识别使用IMD或IFLS的应用的所有安全功能；和 -涵盖IMD或IFLS制造过程。IEC 61557的这一部分将与第8部分和第9部分结合使用。功能安全要求取决于应用，应被视为特定应用总体风险评估的一部分。IMDs和IFLSs的供应商不对申请负责。应用程序设计者负责风险评估和指定整个IT系统的整体功能安全要求，当IMD和/或IFLS的安全功能是IT系统功能安全评估的一部分时，他应选择IMD和/或IFLS的功能安全级别（SIL）。

IEC 61557-15:2014 specifies requirements related to functional safety and is based on the IEC 61508 standard series for the realization of Insulation Monitoring Devices (IMD) as specified in IEC 61557-8 and for Insulation Fault Location Systems (IFLS) according to IEC 61557-9, according to phase 10 of the IEC 61508-1 lifecycle. These devices provide safety related functions for IT systems. This part of IEC 61557 is
- concerned only with functional safety requirements intended to reduce the functional risk during the use of IMDs and IFLSs;
- restricted to risks arising directly from the device itself or from several IMDs or IFLSs working together in a system; and
- intended to define the basic safety functions provided by the devices. This part of IEC 61557 does not
- deal with electrical safety according to IEC 61010-1 and the requirements of IEC 61557-8 and IEC 61557-9;
- cover the hazard and risk analysis of a particular use of the IMD or IFLS;
- identify all the safety functions for the application in which the IMD or IFLS is used; and
- cover the IMD or IFLS manufacturing process. This part of IEC 61557 is to be used in conjunction with Part 8 and Part 9. Functional safety requirements depend on the application and should be considered as part of the overall risk assessment of the specific application. The supplier of IMDs and IFLSs is not responsible for the application. The application designer is responsible for the risk assessment and for specifying the overall functional safety requirements of the complete IT system and he should select the functional safety level (SIL) of the IMD and/or IFLS when their safety function is part of the functional safety assessment in the IT system.