现行国家相关设计规范对火灾时非消防电源的切除提出了明确的规定，但对火灾时切除非消防电源的目的、方式（手动方式或自动方式）及位置并未形成一致的要求。针对这些问题，进行较为深入的分析。明晰了火灾时切除非消防电源的主要原则和目标，即： 避免造成人员恐慌和二次事故；避免火灾的进一步扩大；保证火灾扑救人员的安全，避免造成触电事故；在保证消防救灾的前提下，尽量减小断电范围。最后，结合地铁车站用电负荷及运营管理的特点，提出车站设备区、公共区发生火灾时切除非消防电源的原则、方式及位置。

In the current national design codes and standards, there are definite provisions for the cuttingoff of the nonfirefighting power supply, however, there are no specific provisions on the purposes, manners (manual cuttingoff manner or automatic cuttingoff manner) and positions of the cuttingoff of the nonfirefighting power supply. In this article, analysis is made on the purposes, manners (manual cuttingoff manner or automatic cuttingoff manner) and positions of the cuttingoff of the nonfirefighting power supply. The main principles and purposes of the cuttingoff of the nonfirefighting power supply in case of fire are defined, i.e., trying to avoid passenger chaos and secondary incident, trying to avoid further spread of the fire, trying to ensure the safety of the firefighters and trying to minimize the power cuttingoff scope. Finally, the principles, manners and positions of the cuttingoff of the nonfirefighting power supply in case of fire occurring in the equipment area and public area of Metro stations are proposed on basis of the features of the power load and operation management of Metro stations.