The series SW 705 Magnetic Proximity Switches are available in two broad categories.
• Position sensing switches with Reed Element
• 2-Wire / 3-Wire Magnetic pick-up Sensors
These switches are available in different shapes and sizes. Tubular models are available in Brass/SS enclosures in sizes M12, M18 and M30 and above.
SWITCHES WITH REED ELEMENT (Series SW 705 / 715)
These switches are used only for position sensing application. These incorporate a hermetically sealed sensitive reed element. The object should necessarily be a magnet. These are provided with 2-core built-in cable. The output is a potential free contact & can switch external load directly.
The switching voltage and contact rating depends upon switch size. Special models of latching type switches are available for direction sensing applications.
MAGNETIC PICK-UP SENSORS (Series SW 706 / 716)
These switches are designed to detect the speed of rotating object, such as an engine or motor shaft. These switches senses only ferrous objects / magnets. It consists of an electromagnet that is mounted near the object being measured. The electromagnet produces a magnetic field, which the pickup detects and produces an output voltage proportional to the speed of the object. This output voltage can be used to measure and display the speed of the object, often in revolutions per minute (RPM).
Magnetic pick-up sensors are often used in automotive and industrial applications, such as in tachometers, speedometers, and engine control systems.
HALL EFFECT SENSORS (Series SW 707 / 717)
These sensors can be used only for sensing motion of a ferrous object e.g. Gear Wheel. These incorporate a special high strength ALNICO magnet with a properly designed coil. Special high frequency sensors incorporate a Hall effect sensor. These switches are available in 2/3-wire design. The 3-wire type switches have output logics /operating voltages similar to other types of switches.
The 2-wire switches should be necessarily used with a special controller / amplifier unit.
APPLICATIONS
•Position sensing in hydraulic cylinders
•Roto-meters
•Direction sensing applications
•Level sensing of liquids
•Turbine high-speed sensor
•Bucket Elevator high temperature sensor