These connector level controls join probes to the controller, carrying the signal between them. The number of conductors on the probe coincides with the number of probes in the clamp.

Boiler probes monitor and protect systems by detecting depleted water levels, which prevents heating elements from damaging empty tanks, and can help identify leaks. These probes can withstand high-pressure, high-temperature environments, and are used in the boiler industry where water is heated and boiled, and generators are powered.