KWS Manufacturing

Whirligig Zero Speed Switch

Zero speed switches detect the lack of speed or zero speed in rotating equipment such as a screw conveyor. For conveyors with a tail shaft, a common solution is to use a 4B Components Whirligig Universal Shaft Sensor Mount with a M100 sensor.

The Whirligig is a three-in-one universal shaft sensor mount that includes the target, bracket and guard suitable for all industry standard cylindrical or DIN style inductive sensors. Machine and shaft vibration does not affect the performance of the sensor, as the whole assembly moves with the shaft.

The zero speed switch warns of equipment malfunction through detection of zero speed and provides a signal that is used in upstream control panels to shut down machinery in case of a sudden jam or failure.

Features & Benefits – Whirligig Zero Speed Switch

Exploded View Shows Mag-Con Adapter

The process may be halted to prevent damage or plugging of other conveying or processing equipment. The system’s simplicity makes it a cost-effective way to protect valuable process equipment.


Variety of Mounting Arrangements – Whirligig mounts to a non-magnetic shaft through a drilled and tapped hole at the end of the tail shaft. For carbon steel or another magnetic material, the Mag-Con adapter provides a magnetic coupling with 150 lb. of pulling force.

Enclosed Design – Rotating target is completely enclosed in a tough plastic cover guard. M100 sensor is totally sealed.

Features & Benefits – Whirligig Zero Speed Switch

Whirligig Mounts to Tail Shaft and is Safe for Operators

LED Indication – M100 sensor detects rotating metal target. Integrated light flashes when target is sensed.


Easy Installation – Whirligig can be installed in minutes with minimal tools required. Mag-Con adapter eliminates drilling and tapping of tail shaft.

Operator Safety – Completely enclosed design ensures operator safety. M100 sensor is certified for use in environments rated up to: IEC IP67, CSA / NRTL Class II Division 1 Groups E, F & G approved.

Simple Solution – M100 sensor requires no calibration and provides an output when shaft has stopped rotating.

Features & Benefits – Whirligig Zero Speed Switch

Typical Screw Conveyor with Whirligig Located on Tail Shaft

Features & Benefits – Whirligig Zero Speed Switch

Whirligig is Mounted by Drilling and Tapping End Shaft

Get Connected

CEMA Standard Components and Complete Engineered Systems

Contact Us Online Resources