Limit switch range provides thousands of options

21st November 2006

ES Admin

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Carlo Gavazzi has introduced a comprehensive range of over 8000 limit switches to complement its existing portfolio of position and level sensors. Developed in response to customer demand, the switches are offered in thousands of body, head and contact-block options, both standard limit switches and safety types. There are models with plastic and metal bodies in six different sizes, 10 contact-block variants and over 50 alternative heads in plastic or metal.

Body sizes are from 60mm wide providing three cable inlets, down to 30mm and 35mm with a single inlet. As well as the four standard bodies in plastic and metal, two miniature 30mm versions are available.

Standard plastic bodies are double insulated, providing protection against dust and water ingress to IP65. Manufactured from reinforced UL-V0 thermoplastic fibre-glass, they offer high immunity to electromagnetic disturbances. New metal bodied switches ensure high mechanical resistance, along with IP66 protection. Types PS21 and PS42 are made from zinc alloy (Zamack), whilst the type PS31 and PS43 are aluminium. Miniature versions are offered in either double insulated thermoplastic material or die-cast zinc. Sealing with epoxy resin at the base ensures a higher degree of protection than standard models – IP67 – enabling these devices to operate in underwater applications up to 1m.

Across the board these switches are rated for insulation voltage of 500V and conformity to IEC 947-5-1 (EN 60947-5-1).

Cable gland options for the range include PG13,5, 0.5-inch NPT, PG11, M16 x 1,5 and M20 x 1,5, and there are also pre-wired versions.

Ten different contact block variants are available, featuring Zb type design in which the two moving contacts are electrically separated. Normally-closed contacts feature a positive action, with either a snap action or slow actuation. Snap breaking of moving contacts is independent of the switch actuator’s speed and contributes to regular electric performance - even for slow switch actuator speeds.