Pharmaceutical Checkweighers

Advanced pharmaceutical checkweighers from METTLER TOLEDO achieve accuracy of up to 10 milligrams (depending on product characteristics, conveyor speed, and environmental conditions) with low standard deviation, making them suitable for detecting weight variations less than a single capsule or a broken tablet. FlashCell™ Electro-Magnetic Field Restoration (EMFR) technology enables precise detection of missing components and incomplete fills in packages. These accuracy levels are critical in pharmaceutical production, where even small weight deviations can indicate missing tablets, leaflets, or other critical components that can result in patient safety risks.

Dynamic checkweighers from METTLER TOLEDO are designed for seamless integration into pharmaceutical production environments with minimal disruption to existing operations. Their compact footprint and standardized communication protocols, such as Fieldbus and OPC UA, make it easier to connect them to current line equipment and digital systems without extensive redesign.

In pharmaceutical manufacturing, integration must support strict requirements for product quality, data integrity, traceability, and validation. Our checkweighers can be connected to MES and ERP systems through OPC UA or OPC DA servers, helping enable real-time data exchange, production monitoring, and feedback control. This supports immediate adjustments at the filler or upstream process to reduce product giveaway, avoid waste, and maintain consistent weight accuracy.

These systems can also be integrated with other inspection technologies, such as metal detectors and x-ray systems for contamination detection. A single HMI simplifies operation and training across the line. For manufacturers working with OEMs or complex packaging systems, we collaborate with your preferred partners to deliver flexible, scalable solutions that fit existing workflows and help reduce the need for re-validation.

Professional services are also available to support installation, calibration, validation, and operator training, helping accelerate time-to-production while meeting pharmaceutical industry requirements.

Reliable pharmaceutical checkweighing depends on selecting the right product handling solution for the package type, product size, and production requirements.

For small, lightweight products such as vials, bottles, cartons, pouches, or blister packs, specialized handling options help to stabilize the products, improve spacing, and maintain accurate positioning on the weigh conveyor. This reduces misalignment and minimizes false rejects, which supports consistent weighing performance and contributes to ongoing process stability, reliability, and reduced downtime.

Infeed solutions help prepare products for accurate weighing by improving control and spacing:

• D15 conveyors are smaller, 15 millimeter diameter conveyors that are often used in high-precision weighing applications for handling compact pharmaceutical products
• Adaptors, adaptor plates and nose rollers support critical transition zones between conveyors
• Transfer units use a top belt and bottom conveyors typically placed after a side-grip conveyor in carton applications; they provide smooth transfer in the transport direction and help position products correctly on the load cell for accurate weighing
• Spacing conveyors create or increase the gap between products so that only one item enters the weighing conveyor at a time
• Side-grip conveyors support products by contacting the sides, making them useful for difficult transfers or transitions between different conveyor sizes
• Starwheel side-grip conveyors use guide rails to stabilize items before the starwheel creates the required infeed gap and transfers the product to a side-grip system prior to weighing
• Timing screws gradually increase product spacing as the screw pitch changes along its length, allowing products that enter close together to be separated for accurate weighing

Outfeed and reject solutions should be selected based on product type and how gently the rejected item must be handled:

• Air blast systems use compressed air through a nozzle to blow non-conforming products off the conveyor; this method requires immediate airflow, proper package density, and even material distribution
• Pushers use an air cylinder and plate to gently push rejected products off the conveyor; this is a flexible option for many package types
• Lift gate conveyors are often used in multi-lane applications, where rejected items are allowed to fall below the conveyor; they are especially effective for products that are difficult to divert in the direction of travel

For liquids, bottles, vials, or uniquely shaped containers, specialized sorting methods can help reduce breakage, spills, and tipping:

• Swing gates rotate to guide products toward the collection area using an air-cylinder-driven motion
• Finger sorters with collection platforms provide stable, gentle rejection for bottles and tall products by slowly pushing items aside while keeping containers upright
• Servo rotary sorters use rotating plates driven by a servo motor to quickly move rejected products into the reject bin; this is well suited for high-throughput applications
• Askew package detection protects downstream packaging machinery like case packers and/or shrink foil wrappers

Weighing accuracy depends on sensor sensitivity, product positioning, conveyor speed, and environmental conditions such as temperature, humidity, and vibration. Pharmaceutical checkweighers from METTLER TOLEDO use patented weighing technology, including FlashCell™ EMFR technology with automatic zero-setting or re-zeroing, to provide consistent performance across product batches and deliver the highest accuracy. The modular design and specialized handling options minimize the impact of product misalignment. Regular calibration, validation, and maintenance services help keep systems optimized for specific production environments and maintain accuracy throughout their operational life, supporting product quality and regulatory compliance.

Intelligent pharmaceutical checkweighers can support validation activities through controlled recipe management, electronic storage of critical system settings, and traceable configuration records. These capabilities help manufacturers verify that approved operating parameters are consistently applied and maintained throughout the validated lifecycle of the equipment. In addition, software and configuration management features can support a risk-based approach to change control, helping to minimize the scope of assessment and requalification required when software updates are implemented, in accordance with site validation procedures.

Pharmaceutical checkweighers can be supplied with documentation and service support for Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ), helping manufacturers streamline validation efforts and maintain audit readiness.

With METTLER TOLEDO checkweighers, operating software updates can be managed through a documented change-control process designed to support efficient lifecycle management. Depending on the nature of the change and the site's validation strategy, software updates may be implemented without the need for a full system re-validation, reducing downtime and validation workload while maintaining compliance with GMP requirements.

Pharmaceutical checkweighers can support data integrity programs by generating secure, traceable, and reviewable production records throughout the manufacturing process. Features such as role-based user access, electronic record keeping, audit trails, recipe management, and automatic recording of inspection results help ensure that production data remains attributable, legible, contemporaneous, original, accurate, and complete (ALCOA+ principles).

By providing secure user management and electronic documentation of process parameters, alarms, events, and inspection results, checkweighers can help manufacturers maintain traceability, improve record review processes, and support investigation readiness. Integration with manufacturing and quality systems further enables consistent data capture and strengthens confidence in the integrity of production records across GMP operations.

Modern pharmaceutical checkweighers, such as those from METTLER TOLEDO, can also support compliance with data integrity requirements through features including electronic audit trails, controlled access rights, secure data storage, and documented change management, helping organizations maintain trustworthy records throughout production and quality review activities.

In addition, METTLER TOLEDO intelligent checkweighers are equipped with a broad range of industry-standard communication protocols, connectivity interfaces, and software integration options, enabling seamless connection to manufacturing execution systems (MES), SCADA, historian platforms, and enterprise systems. This supports real-time data exchange, enhanced process visibility, and digitalized production workflows, providing a strong foundation for Pharma 4.0™ and Industry 4.0 manufacturing strategies.