What's the minimum separation required between 110v AC lines and power limited cables inside a FACU?

The minimum separation required between 110v AC lines and power limited cables inside a Fire Alarm Control Unit (FACU) is indeed 1/4 inch. This separation is important to prevent electromagnetic interference (EMI) that could affect the signals transmitted through the power limited cables. Such interference could potentially disrupt the functionality of the fire alarm system, compromising its reliability and effectiveness in emergencies.

Maintaining this specified distance helps ensure that the power limited circuits, which carry low voltage for signaling and detection, are protected from the higher voltage AC supply lines. The regulations governing this separation are designed to safeguard both the integrity of the fire alarm system and overall safety within the facility. Adhering to these specifications is a critical part of fire alarm installation and maintenance standards.