Coaxial cables used in power-limited fire alarm systems must have an overall insulation rating of not less than_______.

In power-limited fire alarm systems, coaxial cables play a critical role in ensuring reliable signal transmission while maintaining safety standards. The overall insulation rating for these cables is crucial as it determines their ability to handle voltage without risk of electrical failure or hazards.

For power-limited fire alarm systems, a minimum overall insulation rating of 300V is required. This rating ensures that the cables can safely operate and contain the voltage levels typical in these types of systems, which helps in preventing insulation breakdown that can lead to short circuits or electrical fires. This standard is established in line with the National Electrical Code (NEC) and other regulatory guidelines, which strive to protect both the system integrity and the safety of occupants.

Using cables with an insulation rating lower than 300V in power-limited systems might not provide adequate protection against electrical surges or faults, potentially compromising the system's functionality and safety. Thus, selecting cables with a 300V rating meets the necessary electrical safety criteria while maintaining reliability in fire alarm system operations.