What is fork type level switch?
A tuning fork switch comprises a two prong fork which is driven to oscillation at its natural frequency, usually by a piezo-crystal assembly. The switch is usually mounted on the side or top of a tank using a flange or threaded process connection such that the forks protrude into the tank.
What is tuning fork level sensor?
These instruments are designed based on the tuning fork principle for providing point level detection for alarm, monitoring, and control applications. When in air, the tuning fork vibrates at its natural frequency, but when immersed in a particular medium, the frequency drops and provides an output state change.
How does a fork sensor work?
The vibrating fork type level sensor works on the principle of tuning forks. When the fork comes in contact with liquids/solid material, the frequency slightly changes, and this change in frequency is sensed by the electronic circuit which in turn send out a signal.
How does a vibrating fork point level detector work?
When in air, the forks vibrate at their natural frequency. When liquid covers the forks, the frequency drops. Changes to the frequency are continuously monitored by the switch electronics, which then change the output state to operate an alarm, pump, or valve.
What is tuning forks principle?
An electronic circuit continuously excites the tuning fork, causing it to mechanically vibrate. When the prongs of the fork contact anything with substantial mass, the resonant frequency of the fork decreases. The circuit detects this frequency change and indicates the presence of mass contacting the fork.
What is vibration level switch?
The vibration type level switch oscillates a rod (stainless steel) using an electronic circuit. When this vibration rod touches material in a tank, its vibration stops and outputs detection signal. Our vibration level switch vibration rode has only high sensitive at its tip.
What is the unit of measurement for vibration?
Vibration can be expressed in metric units (m/s2) or units of gravitational constant “g,” where 1 g = 9.81 m/s2. An object can vibrate in two ways: free vibration and forced vibration.
Why is tuning fork used?
Tuning forks, typically aluminum, consist of a stem (handle) and two prongs that form a U-shaped fork (Figure 4-13). The tuning fork vibrates at a set frequency after being struck on the heel of the hand and is used to assess vibratory sensation and hearing (air conduction and bone conduction).
Which level switches is non power?
Float and Displacer operated level switches are considered mechanical devices because of their moving parts, the buoyancy principle of operation and because they don’t require a power supply.
How does a tuning fork level switch work?
Tuning Fork Level Switch uses a metal tuning fork structure to detect the presence of a liquid or solid (powder or granules) in a vessel: An electronic circuit continuously excites the tuning fork, causing it to mechanically vibrate. When the prongs of the fork contact anything with substantial mass, the resonant frequency of the fork decreases.
How does a vibrating fork level sensor work?
The working principle of vibrating fork level sensor is based on vibrating a tuning fork sensor continuously at its natural frequency and detecting the change of frequency and amplitude in the presence of application media. The monitoring process of given parameters depends upon type of application media.
What is the principle of a level switch?
The level switch is designed using the principle of a tuning fork. A piezo-electric crystal oscillates the forks at their natural frequency. Ch anges to this frequency are continuously monitored. The frequency of the vibrating fork sensor changes depending on the medium in which it is immersed.
How does the frequency of a fork sensor change?
The frequency of the vibrating fork sensor changes depending on the medium in which it is immersed. The denser the liquid, the lower the frequency. When used as a low level alarm, the liquid in the tank or pipe drains down past the fork, causing a change of natural frequency that is detected by the electronics and switches the output state.
