CLS : Level Switch

Model : CLS
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Capacitance Type Level Switch

A capacitance is formed between the probe and the vessel wall. As the level of the measuring medium rises or falls capacitance between the probe and vessel wall changes proportionately. A high-frequency sine wave is applied between the probe and tank wall. A change of medium level will induce a change in the current of the applied sine wave. From when the capacitance in the vessel increase, the impedance will decrease and the current will increase, and vice-versa. Head-mounted electronics converts the capacitance variation and accordingly switches the controller
ON or OFF. With no moving parts, it is free from wear and tear, rugged, and robust in construction. No dead zone like float-based instruments. It must be ensured that the probe is parallel to the tank wall throughout its length.

  • No moving parts, it is rugged and robust instrument.
  • No dead band or dead zone like float based/ultrasonic instruments.
  • Trim-Pots for span and zero adjustment.
  • Plug and play with reference probe and rod.
  • Remote electronics as option with 2 Metre long coaxial cable.
  • Standard enclosure weather proof-cast Aluminium or Nylon 66.
  • Flame proof as optional.
  • Our new introduction is Micro processor based Blind Switch.
  • Suitable for operation from 12 to 32 VDC, with reverse polarity protection.

Additional information

Frequecy of operation

5 to15kHz.

Probe Material

Stainless Steel / Teflon insulated 10/12/16 mm rod up
Max 3 Metre length

Process connection

3/4",1",1.1/2" BSP(M) or 1 "ASA 150 lbs flanged but thickness 12mm
(or as per customer specification)

Power supply



1 SPST or 2 SPST

Span & Zero adjustment

Trim pots

Max.Working Pressure


Max.Working Temp.



±0.5%, ±1% or ±2%


Cast aluminium weather proof with PG9 cable gland or Flame proof
(IS2148-2004,Gr II A and B gases); Optionally available for Gr. IIC
gases also.

Cable Size

3 core, 0.75 screened PVC cable.