Tuning fork vibration level switch is caused to vibrate by the resonance of the piezoelectric crystal. When effected by the material damping, 

the amplitude suddenly reduces, then the frequency and phase change significantly. These changes will be detected by the internal electronic circuit, 

and be transformed into a switching signal output. The product can monitor, control and alarm the high and low bit of tanks. 

Also it is suitable for a variety of liquid, powder, granular solid. It is practical， simple， reliable， adaptable and maintenance-free. 

The tuning fork and output have working condition and diode indicator, which can be adjusted as habit. 

Also it has two power supply input modes(220V AC and 24V DC) and many power supply output modes(DC output type, 

DC voltage output type, relay contact output type). All types have high and low alarm sets, which can be done sensitivity setting according to the situation.