System for detecting contamination condition of lubricating grease of mechanical component and bearing system

A system for detecting contamination condition of lubricating grease of a mechanical component, the system comprising:

• a radio frequency signal generator configured to generate a radio frequency signal with a frequency higher than 1.0 GHZ;
• a sensor comprising a sensing assembly configured to contact lubricating grease to be sensed in the mechanical component;
• a switch assembly configured to switch between a first mode and a second mode;
• and
• a radio frequency signal analyzer;
• wherein when the switch assembly is in the first mode, the radio frequency signal is transmitted via a first transmission path, thereby providing a first feedback signal for the radio frequency signal analyzer, and when the switch assembly is in the second mode, the radio frequency signal is transmitted via a second transmission path, thereby providing a second feedback signal for the radio frequency signal analyzer, the second transmission path including the sensing assembly, the first transmission path being the same as the second transmission path except the first transmission path comprises a short instead of the sensing assembly, the first feedback signal provided by the first transmission path being representative of the second transmission path without the sensing assembly;
• and
• wherein the radio frequency signal analyzer is configured to perform an analysis based on both the first feedback signal and the second feedback signal to detect the contamination condition of the lubricating grease.