Air Gap monitoring (Rotor/Stator)

Capacitive Air Gap Measuring Chains
Gearless Mill Drive
U.S. Patent No. 11125795
The VM™GMD sensor is designed with a thin body and a wide measuring range that allows monitoring of small and large air gaps. VMGMD air gap sensors are easy to install without removing the rotor or poles. These sensors are resistant to chemicals and solvents commonly used during installation. During operation, they are immune from strong magnetic fields, carbon dust, and deposits of oil. Each VMGMD air gap measuring chain is composed of a passive, non-contact capacitive sensor that measures the distance between its surface and a metallic target. The raw signal picked up by the sensor is sent to a conditioner through a triaxial extension cable to be converted into a linearized 4 to 20 mA signal. Different measuring ranges are available to adapt to different machine air gaps.