What determines the distance a fire alarm circuit can cover without a repeater?

The distance a fire alarm circuit can cover without a repeater is primarily determined by the gauge of wire used. Different wire gauges have different resistance levels: a smaller gauge (thicker wire) has less resistance and can carry signals over longer distances with minimal voltage drop. This is fundamental for maintaining consistent communication between system components without losing signal strength, which is critical for reliable operation of the fire alarm system.

Other factors like the type of fire alarm system, the amount of current flowing, and the configuration of the building can influence performance, but they are not direct determinants of the distance without a repeater. The wire gauge directly impacts how far the signal can travel while still ensuring functionality and compliance with fire safety standards.