Vibrating Fork Level Switch

Salient Features :

Fast and Easy Installation
No Calibration.
No effect of electrical properties of the Service material
High Reliability.
Suitable for highly dusty environment.
Suitable for grain size up to 20 mm.
Field selectable operation logic.
Can be configured either for High or Low-Level point switching.

Measuring System

The complete system consists of:
The sensing probe of Vibrating Fork and The Electronic Switching unit.

The electronically stimulated fork vibrates at its mechanically resonance frequency of about 125Hz/400 Hz when the fork is free of the service material. The resonance is caused by the piezoelectric crystals. One of the piezo crystals produces a small voltage which is transmitted to the switching amplifier. If the fork is covered by the bulk material, a damping effect is produced and the piezo crystal does not produce the voltage and the amplifier will switch and a corresponding signal output is actuated. The vibration of the fork has self-cleaning properties.

The light deposit on the container wall does not affect the operation of the Instrument

Technical Specifications

Switching Unit
Housing	Aluminium, Integral with the probe/suitable for back panel mounting.
Cable Entry	12-%" NPT
Ambient temperature	0^o C ti +60^o C
Power consumption	2 VA
Main Voltage	230/110 V AC(+/-15%), 50 Hz OR 24 V dc
Output	2 sets of potential free contacts rated at 5 amps, 230 V AC for non-indctive loads.
Switching delay	Continously adjustable 2 to 20 Sec (Probe Free of material or probe covered with material).
Safety operation	Field selected switch for Minimum or Maxmimum. (FSL/FSH) switching points.
Switch status display	Green LED shows Normal Red LED shows alarm
Fork (SENSING PROBE)
Mounting	Screwed – 1"BSP or Flanged
Sensor	Fork, Stainless steel
Lenght	120 mm (standard) upto 3000mm (for Liquids) 200mm (standard) upto 3000mm (for Solids)
Extension	Pipe Operating Temp in
Vessel	150 deg for the integral switching unit.