SIGMA's Pneumatic Level Switches are used in application where electrical switching is not recommended or electricity is not available. The working principle is the same, except that the magnet indirectly actuates a 3/2 valve for changeover. This 2 system requires minimum 2 kg/cm clean filtered air, preferably through an AFR.

Side Mounted (with / without cage) : Buoyancy force of process liquid on a float causes the float to move with the liquid's surface. Float movement pivots a magnet into the field of a like-charged switch magnet. As the magnets repel each other, the switch magnet moves, actuating the switch.

Top Mounted :Float / Displacer (with / without cage) : Operation is based upon simple buoyancy, whereby a float or a spring loaded weighted displacer rises following the liquid level. A magnetic sleeve, connected to the float / displacer, moves up and operates within a non-magnetic enclosure tube. The magnetic sleeve attracts a pivoted magnet, actuating a switch mechanism located out-side the enclosure tube to give NO or NC changeover. A fall of liquid level will de-actuate the switch mechanism

SIGMA's Pneumatic Level Switches are used in application where electrical switching is not recommended or electricity is not available. The working principle is the same, except that the magnet indirectly actuates a 3/2 valve for changeover. This 2 system requires minimum 2 kg/cm clean filtered air, preferably through an AFR.

Side Mounted (with / without cage) : Buoyancy force of process liquid on a float causes the float to move with the liquid's surface. Float movement pivots a magnet into the field of a like-charged switch magnet. As the magnets repel each other, the switch magnet moves, actuating the switch.

Top Mounted :Float / Displacer (with / without cage) : Operation is based upon simple buoyancy, whereby a float or a spring loaded weighted displacer rises following the liquid level. A magnetic sleeve, connected to the float / displacer, moves up and operates within a non-magnetic enclosure tube. The magnetic sleeve attracts a pivoted magnet, actuating a switch mechanism located out-side the enclosure tube to give NO or NC changeover. A fall of liquid level will de-actuate the switch mechanism