An investigation of low voltage arc flash exposure

摘要

The distribution utility lineman, servicer, and meter technician play an active role in the operation, installation, and maintenance of 120-volt and 240-volt equipment on a daily basis. The arc flash risks faced by utility workers operating equipment energized at 240 V or less were investigated for activities involving meter enclosures, meter installations, meter maintenance, and the connection of conductors in energized transformers and power pedestals. The investigation led to conclusions regarding the likelihood of an injury due to an arc flash exposure to utility workers performing low voltage work. The investigation included tests conducted at an installation located immediately adjacent to a substation to achieve fault currents near 12,000 amps, more than which is typically expected for the daily activities performed by utility linemen on voltages 240 Volts and below. It was concluded that the low voltage arc flash energy level to which these workers are exposed is very low. The methodology and results will be explained.