These float switches work like a standard light switch, they open and close contacts to control whether or not signal current can pass through. When they are closed, the current is flowing and when they are open, the current is not flowing. The "normal" state is when the float switch is down, resting on it's cable or float stop. Some float switches have hysteresis built-in which tells the pump not to chatter, but to turn off at one level, and turn on only at another level. The floats have multiple up to four switch points in a single float. Many float switches are simply used for level indication.
