What kind of device is a probe type low water cut off?

A probe type low water cut-off uses a system of submerged probes to detect the water level within a boiler or steaming system. This device operates by utilizing electrical conductivity; when water is present, it completes a circuit between the probes. As the water level falls, fewer probes are submerged, which eventually interrupts the circuit and triggers the cut-off mechanism. This is crucial for preventing a dry-fire condition in boilers, which can lead to overheating and damage.

The design and functionality of the submerged probes make this system highly reliable for monitoring water levels, as it directly responds to the presence or absence of water. It offers advantages such as fast response times and reduced maintenance compared to mechanical systems. This is why the correct choice focuses on the submersion of probes as the primary mechanism of action, distinguishing it from other types of level detection methods that do not employ this technology.