Mettler-Toledo checkweigher measures up to ATEX safety standards

GIESEN, Germany - Manufacturers and production lines for food, pharmaceuticals, cosmetics and fast-moving consumer goods may benefit from the improved safety protection added to the ATEX certified checkweigher by Mettler-Toledo Garvens. The model has a weighing sensitivity that minimises the instance of costly product giveaway and an advanced design to comply with European ATEX safety requirements for devices used in areas at risk of explosion. Featuring an anti-static belt conveyor, the checkweigher is also suitable for the inspection of small, lightweight products.

The European Union Directive 94/9/EC (ATEX 95) stipulates essential safety requirements for equipment used in explosion hazard zones, such as those involved in the production of dusty, powdered products or flammable gases and aerosols. These materials can, in the right quantities, and with an appropriate source of ignition, cause an explosion.  ATEX standards classify such production lines into zones according to the nature and gravity of the explosion risk to specify appropriate devices. Prior to selecting equipment for the line, manufacturers must also ensure they acquire zone confirmation documentation, including all the information necessary to enable suppliers to offer the most appropriate solutions for compliance.

In addition to offering exceptional levels of weighing sensitivity, the XS3 checkweigher has been certified by ATEX assessors as a Category 3 device, making it suitable for use in Zone 2 gassy environments (Category 3G) and Zone 22 (Category 3D) dusty atmospheres. The system’s conveyor belt, designed for the transport of lightweight products, is made from anti-static plastic, which, combined with the conductive stainless steel shell, encasing the conveyor motor and weigh cells, minimises the risk of sparks caused by the build-up of static charge.  

The control cabinet – which is one of the three main components of a Mettler-Toledo Garvens checkweigher – has been designed as a hermetically sealed enclosure to avoid any contact of the ambient, potentially explosive atmosphere with the electronic and electric elements protected inside the cabinet. Antistatic materials have also been used in the construction of the operating terminal to further reduce the risk of electrical sparks that could be an ignition source. What is more, special connector feeds for cabling, as well as energy limitation features for switches and sensors, have been developed to maximise explosion protection.

 “Each section of the ATEX XS3 checkweigher, including the weighframe, operating terminal and control cabinet has been constructed specifically to meet the strict requirements of the safety standards”, said Thorsten Germersdorf, product manager. “In most scenarios onlyAir Jordan