Production monitoring in EX Zone 0, acetone vapor
Cellulose is a versatile material, the best known and most common application being as the basis for paper production. However, cellulose fibers are also suitable for other products, for example as a raw material for filters. In order to be used as a filter, however, the cellulose requires a pretreatment that also involves the use of the highly explosive acetone. Continuous production control in this environment is difficult, but possible with so-called Namur sensors. In the described plant in the Brazilian state of Sao Paulo, about 1000 of these sensors (EXi) are used.
Of course, such an installation can be wired in the EX zones in the classical way with appropriate sub-distributors and complex installation technology. However, there is a much better option that not only significantly reduces the installation effort and costs, but also offers additional diagnostic possibilities.
In diesem Projekt wurden dafür 300 spezielle AS-Interface Module der Firma Sense eingesetzt. Die gesamte Fertigungsanlage am Standort besteht aus 14 Maschinen, die jeweils mit einem AS-Interface Netzwerk ausgerüstet.
In this project, 300 special AS-Interface modules from Sense were used for this purpose. The entire production line at the site consists of 14 machines, each equipped with an AS-Interface network.
AS-Interface offers the simple wiring and connects sensors and actuators with the control system. For this purpose, the AS-Interface transmits power and data for the connected nodes on a two-wire cable.
AS-Interface itself is used for wiring in zone 1 and 2. With AS-Interface, the power supply for all connected devices is routed via one cable, which offers the advantages in wiring and saves additional lines but brings additional potential ignition energy into the hazardous areas.
For this reason, the system is only used as far as Zone 1, from where the Namur sensors are then routed into hazardous Zone 0.
This installation was made possible by the ASI3.2-MD-4EN-Ex modules from SENSE, which have the appropriate approvals for use in such environments. Further information about the module at: https://www.sense.com.br/produtos/detalhes/1440013/por/3/144/redes-industriais/modulos-i-o-asi-md/ASI3.2-MD-4EN-Ex