Filling level indicators serve for reliable monitoring and signaling of the product levels in silos, hoppers and containers etc. They can be used as full, request or empty indicators in zone 10 areas (§ 8 lex V) subject to dust explosions. Due to their sturdy and enclosed design, they are insensitive to external influences such a high or low pressure, build up of static electricity, bulk material residue on the probes and strong dust formation.
Full indicator: When during the filling operation of silos or containers the product column rises and reaches the rotating blade, the slowly moving rotor is stopped. This causes the asynchronous motor in the body to change its position and to actuate a microswitch which emits a \\\"full\\\" signal. The rotor is stationary until the decreasing product level frees the rotating blade. The motor then returns to its initial position.
Request, empty indicator: When product is discharged and the level falls, the stationary rotor blade of the request or empty indicator is freed which causes a warning signal or switching impulse to be transmitted to the control system.