With the use of the I-7242D external module, the NPE/iMod industrial computer is perfect for control and management of the objects in the DeviceNet networks. The communication between the module and the computer is carried out through the Modbus RTU protocol. Next, all the data can be transferred to a local HMI or using the GPRS - to a control station.
Networks using the DeviceNet protocol are widely used in communications between a PLC and the I/O devices. An unquestionable advantage is that it can be powered directly with a data transmission cable and the fact that it is an open standard. This network enables connection up to 64 devices, the cable length can reach up to 500 metres.
The DeviceNet networks are mainly used in Industrial Automation. The main features are easy installation, high efficiency and minimum number of cables. The use of the NPE/iMod computer enables transfer of collected data through the GPRS network - it reduces the number cables used for installation. This solution is all the more beneficial since you can get access to data from the control panels hundreds of kilometres away.
The communication between the telemetric module and the converter is carried out through the RS-485 interface and the modbus protocol. The I-7242D module works as a Gateway - it connects DeviceNet slaves to Modbus RTU masters. The converter is fully transparent, which means that all the data from controlled objects are sent directly to NPE/iMod.
PostgreSQL Server for Embedded Computers
The PostgreSQL database support has been recently added to the NPE/iMod functionalities. Due to this functionality an industrial computer can operate both as an SQL database server and an SQL client. In order to make the PSQL support easier, we created a built-in module for the innovative NX Dynamics Web interface. This module fully supports both local and external PostgreSQL database in accordance with the SQL syntax. It enables an easy database connection as well as viewing and modifying the tables in the database.
All the typical SQL queries supported by PSQL are fully compatible with the module. In case of entering a wrong SQL query or an error in the syntax the module returns the error and points to the place where it occurred. In addition, the NXDynamics package module can save the set data and SQL queries, so you can easily look through the content of a set table. With the included, free of charge SDK, you can easily modify the module according to your needs.
A work time recorder might be a good example - a system supervisor modus rtu can easily control the working time of employees by monitoring the archived data. With the use of simple SQL queries you can easily preview the recorded in/out time of selected employees and adjust the presentation of data according to your preferences. The NXDynamics Web interface is available on every device, so each NPE/iMod user can write an SQL query in a fast