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, buildup and moisture and is ideal for primary industries including mining, aggregate, and cement.

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  • Up to 100 mm (4") gap measuring range
  • Rugged, low maintenance suitable for tough environments
  • Provides cost-effective protection
  • Visual indication of target triggered pulse
  • Maximum 3000 pulses per minute


Power Supply

115 V AC/50 to 60 Hz, 7 VA 

230 V AC/50 to 60 Hz, 7 VA 

± 10 % of rated voltage

1 SPDT Form C relay
Operating Temperature

-40 to 60 °C (-40 to 140 °F)



2"NPSL process mounting

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To remain competitive, companies in industry must ensure – and ideally increase – the availability and productivity of machines and plants. As your partner, we offer a unique range of services and support based on our extensive technology and industry expertise.

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As your partner, we offer a unique range of services and support based on our extensive technology and industry expertise. With our offerings, you can expect a high degree of reliability and a successful digital future for your company.

Well trained for excellent handling

Receive standardized or individual expertise directly from the manufacturer – with training centers in more than 60 countries.

Safety integrated

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.


How can we help you?

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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