SITRANS WM100 is a heavy-duty zero-speed alarm switch. This non-contacting unit provides cost-effective equipment protection even in the harshest conditions. This rugged unit is impervious to dust, dirt, build-up and moisture and is ideal for such primary industries as mining, aggregate, and cement. Operating where other systems are prone to failure, the non-contacting design eliminates the need for lubricating, cleaning and part replacement. Downtime and clean-up expenses associated with conveying equipment failure are reduced by the SITRANS WM100. It alarms to minimize spillage, prevent extensive damage or even fire caused by belt slippage at the head pulley and warn against conveyor malfunction. The SITRANS WM100 has built-in selectable start delays and 1 Form C relay contact. With an aluminum body, it operates from -40 to +60 °C (-40 to +140 °F). Key Applications: tail pulleys, driven pulleys, motor shaft sensing, screw conveyor flights, bucket elevators

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  • Up to 100 mm (4") gap between SITRANS WM100 and targets

  • Rugged, low maintenance suitable for tough environments

  • 1 SPDT Form C relay contact

  • Provides cost-effective protection

  • Visual indication of target triggered pulse


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Safety is key in the process industries. A failure in instruments relevant for safety may have serious implications for humans, the process and the environment. Therefore, a wide range of our process instruments come with on-board safety features for maximum risk reduction.


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Whether you need to measure pressure, temperature, flow, level or weighing, Siemens has best-in-class instruments to suit the unique needs of your plant or application - along with a global network of technical support available 24 hours a day, 7 days a week. Our high-performance and cost-efficient range of industrial solutions also includes devices for valve positioning, process protection, recording, controlling, communication and more.

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