Paddle Switch Working Principle

Paddle Type Level Switch is used for level detection for powder or bunk material in silo,hoppar,etc.

The rotating paddle is continuously rotates by a motor. When this paddle contacts with the material, the force more than the rotating torque will be applied to the paddle and the rotation will stop.

The Level Switch detects rotation ⇔ stop and outputs the contact.

Principle

The principle is based on the moment of resistance change of a rotating paddle in air or a medium.

The electrically driven, slowly rotating paddle (frequency = 1Hz) is on the level of the selected limit.

The rising product brakes the rotation, the hinge-mounted drive system changes its position and triggers a microswitch.

As the level moves down, the drive returns to its original position by spring force and the microswitch restarts the motor.

Applications

Point level detection in bulk solids

The universally usable paddle point level switch is employed as a full, empty and requirement alarm in silos with bulk solids.

Advantages

Automatic rotation monitoring (optional)

Recognition of failures without dismantling the instrument

Easy installation

Robust plastic housing with transparent cover

Cover securing device

Density setting without any tools

Article Source: Endress+Hauser

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