What activates the bilge pump in a system?

The bilge pump in a system is typically activated by a float switch. This device is designed to detect the level of water in the bilge. When the water level rises to a certain point, the float switch is triggered, which then sends a signal to activate the bilge pump. This mechanism is crucial for preventing water from accumulating in the bilge, which could lead to flooding or other issues on a vessel.

Using a float switch ensures that the bilge pump operates automatically, providing a reliable means of managing water levels. It responds to changes in water level, activating the pump only when necessary, which helps to conserve energy and prolong the life of the pump.

In contrast, other options like pressure switches, tilt sensors, and temperature controls are not typically used in standard bilge pump operations. A pressure switch might be used in different contexts where pressure levels are critical, a tilt sensor would monitor angles and orientation rather than water levels, and temperature controls relate to thermal conditions rather than fluid management. Therefore, the float switch is the most appropriate and effective choice for activating a bilge pump.