The float switch is a very important device to control the liquid level of the tank. The float switch can automatically control the start and stop of the pump according to the variation of required liquid level, with no need of a special person to care about, making operation quite easy.
When the level is lowered, the float sinks, and the contact point inside the switch is closed. This contact point can be used to control the metering pump. For example, it can stop the metering pump 1 and start the metering pump 2. On the other hand, it also can indicate that the cartridge is empty by turning on the alarm/indicator light. And the float switch can be applied to the tank to indicate that the tank is full and to stop the metering pump.