Weighing module SIWAREX WP321

The weighing electronic SIWAREX WP321 is a technology module for the distributed I/O system SIMATIC ET 200SP. Due to the diversity and the flexibility of the SIMATIC manager and TIA Portal, it is possible to realize best solutions for small and medium automation systems. SIWAREX WP321 covers typical tasks of non-automatic scales: Both level measurement in silos and bunkers and platform scales can be seamlessly integrated in the automation environment. The internal update rate of 100, 120 or 600Hz allows a fast and accurate force measurement, too. Scales in hazardous areas (if so with Ex-interface SIWAREX IS) can also be realized. The configuration package and the “ready for use” sample application offers a very fast development and implementation of customer- and industry specific solutions. SIWAREX WP321 can be integrated and used in SIMATIC Step7 V5 as well as in TIA Portal.

Industry Mall

Select and order


  • Uniform structure and universal communication through the integration in  I/O SIMATIC ET 200
  • Parameterization of the scale via operator panel, CPU or PC
  • Flexible configuration possibilities in SIMATIC TIA Portal resp. SIMATIC Step7 V5
  • Measuring of weight and force with a resolution of up to +/- 2 million parts
  • 600 Hz measuring rate (high speed)
  • 100/120 Hz measuring rate (efficient 50/60Hz interference frequency suppression)
  • Scale internal control of freely definable  limit values
  • Easy commissioning  via software  SIWATOOL without SIMATIC knowledge
  • Automatic adjustment without adjustment weights possible
  • Replacement of module without a new adjustment of scale
  • Direct use in ATEX zone 2 possible
  • Various status- und diagnostic information
  • „Ready for use“  sample application

Technical specifications

Integration in automation systems

SIMATIC S7-300/400



Communication interfaces
RS485 (SIWATOOL) via USB-RS485 converter (please consider the notes in the manual) 
Internal resolution
Up to +/- 2 million parts

Download, Support, Services

Find downloads, support and services for Siemens Weight Measurement

The fastest way to the experts

Proposed solutions for your queries and direct access to our experts in Technical Support.

Service offers

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.

Service catalog

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.

Your direct line to Siemens

Contact your regional partner