There has been prior research exploring the exposure of common electrical cords and cables to fire, but that has traditionally been at the lab scale and under near steady-state exposures. The goal of these experiments was to expose six types of cords and cables in a room-scale compartment with a fuel load sufficient to drive the compartment through flashover. The basic test design was to expose the cords and cables on the floor of a compartment to a growing fire to determine the conditions under which the cord/cable would trip the circuit protection device. All of the cords were energized and installed on a non-combustible surface. The six cables and cords were protected by three different circuit protection devices which were remote from the thermal exposure. This configuration resulted in 18 exposures per experiment. The room fires experiments consisted of three replicate fires with two sofas as the main fuel source, two replicate fires with one sofa as the main fuel source and one fire with two sofas and vinyl-covered MDF paneling on three walls in the room. Each fuel package was sufficient to support flashover conditions in the room. The average peak heat release rate of the sofa fueled compartment fires with gypsum board ceiling and walls prior to suppression was 6.8 MW. The addition of vinyl covered MDF wall paneling on three of the compartment walls increased the pre-suppression peak heat release rate to 12 MW. In each experiment during post flashover exposure, the insulation on the cords and cables ignited and burned through, exposing bare wire. During this period, the circuits faulted. Assessments of both the thermal exposure and physical damage to the cords did not reveal any correlation between the thermal exposure, cord/cable damage, and trip type.

中文翻译：

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闪络火灾条件对外露带电电线/电缆的影响

之前已经有研究探索常见的电线和电缆暴露于火中，但传统上是在实验室规模和接近稳态暴露的情况下进行的。这些实验的目标是将六种类型的电线和电缆暴露在一个房间规模的隔间中，其燃料负载足以驱动隔间通过闪络。基本的测试设计是将隔间地板上的电线和电缆暴露在不断增长的火中，以确定电线/电缆在何种条件下会使电路保护装置跳闸。所有的电线都通电并安装在不可燃的表面上。六根电缆和电线由远离热暴露的三个不同的电路保护装置保护。这种配置导致每次实验 18 次曝光。房间火灾实验包括三个以两张沙发为主要燃料来源的复制火，两次以一张沙发为主要燃料来源的复制火，以及一个以两张沙发和乙烯基覆盖的中密度纤维板在房间的三面墙壁上的火。每个燃料包都足以支持房间内的闪络条件。在抑制之前，石膏板天花板和墙壁的沙发燃料隔间火灾的平均峰值热释放率为 6.8 MW。在三个隔间壁上添加乙烯基覆盖的 MDF 墙板，将预抑制峰值热释放率增加到 12 MW。在闪络后暴露期间的每个实验中，电线和电缆上的绝缘体被点燃并烧穿，暴露出裸露的电线。在此期间，电路出现故障。