ISaGRAF

ISaGRAF is the instrumental graphical environment of development of application programs for the programmable logic controllers (PLC) in languages of the IEC 61131-3 and IEC 61499 standard allowing to create local or distributed control systems.

Fundamentals of technology — the application development environment (ISaGRAF Workbench) and the executive system (ISaGRAF Runtime) adapted for different hardware-software platforms.

2015: ISaGRAF ACP 6.4 и ISaGRAF 6 Target

Webinar "New versions: ISaGRAF ACP 6.4 and ISaGRAF 6 Target" (2015)

In a webinar an idea of the changes executed in the application development environment for ISaGRAF ACP 6.4 controllers and executive system of ISaGRAF 6 Target on the basis of the version of a packet of PRDK 5.50 is given.

2014

ISaGRAF 6.1

The ISaGRAF software package - built in software and work benches of industrial automation compatible to the IEC 61131-3 and IEC 61499 standards. ISaGRAF 6.1 includes important innovations in a development environment (Workbench) and new version 5.3 of C5 of the environment of execution (firmware). Having powerful tools of Microsoft Visual Studio 2010 in the basis, now ISaGRAF 6.1 Workbench became much quicker, offers the new and advanced user interface and expanded management of packets.

ISaGRAF 6.1 Workbench is a modular and flexible environment which gives the chance to users to add or delete components. Each component in Workbench was developed on ISaGRAF technology on the basis of Microsoft®. net Framework which is called the Single Platform of Automation (ACP, Automation Collaborative Platform), and performs interaction by means of this technology. ISaGRAF ACP provides capability to add or delete different plug-ins for accomplishment of special requirements of a product of automation.

ISaGRAF 6.1 includes interfaces of program expansions (plug-ins, plugins) for adding of new opportunities and also plug-ins for implementation of a number of functions which made so popular ISaGRAF 5 among customers worldwide. The editor of IEC 61499 is again provided to ISaGRAF 6.1 Workbench. Other available languages include the LD, FBD, ST, SFC languages and SAMA.ESHCHE of one function important and available now in this last release control of versions (Version Source Control) which provides means for joint work of several users over the same elements (for example, such as device, resource, POU) by means of registration of an input and output from a system is. It also gives the chance to users to work with several versions of the project, to create backup copies and to recover the whole drafts or separate elements of the project and to compare the files executed in different versions. Interruption of the user (User Interrupt), failure recovery (Failover), a dependency tree (Dependency Tree), library of blocks, the monitor of blocking of variable (Variable Lock Monitor) and the status of the controller (Controller Status) belong to other new opportunities of ISaGRAF 6.1. As different types of applications require different types of interruptions (for example, time, an impulse, an input/output...), implementation of interruptions in ISaGRAF is provided using a set of work benches (toolkit) which allows manufacturers of the equipment (OEM manufacturing) to define and display the interruptions in the ISaGRAF application. Toolkit also includes plug-ins for configuring and programming of interruptions by the end user.

Failover is an operation mode at which functions of a management system are assumed by a secondary management system in that case when the main system becomes unavailable because of a hardware failure or at the planned idle time. This function is used to make a management system of more fault-tolerant. Function of failure recovery in ISaGRAF 6.1 gives the chance to users to modify solutions of management and to change conditions under which the controller receives or runs away. The plug-in implementing a dependency tree (Dependency Tree) gives to users a complete overview of all coupled elements in the application so they can see all dependences of variables and also the ascending and descending dependences for each variable. The library of blocks is an improvement of the user interface which gives to users the chance to drag (drag and drop) any function or functional unit in the program instead of implementation of the choice from the selector of blocks. Functions and functional units are context-dependent from the selected project, the device or a resource, they are grouped in the range or category, and users can execute search of the name of the block also. The monitor of blocking of variables (Variable Lock Monitor) outputs the list of all blocked variables.

Function of the status of the controller (Controller Status) provides users with the main information on the controller, including the version of the project with which they work and also time of a cycle and number of the blocked variables. New version 5.3 of C5 Firmware has several new templates, including, templates of Microsoft Windows and Linux for new features of the user interruption and failure recovery. Priorities of SFC for simultaneous transition in case of OR branching are among other new characteristics. ISaGRAF 6.1 still include the free version consisting of ISaGRAF Free Firmware working at the platform of XP Embedded, the 32-and 64-bit version of Windows XP®, Windows Vista® & Windows 7® and completely functioning version of ISaGRAF 6.1 Workbench using which developers can create the finished applications. ISaGRAF Free Firmware includes the Modbus TCP Client drivers and also Modbus TCP Server.

The mode of reservation and recovery (Failover) in ISaGRAF 6.1

In ISaGRAF 6.1 support of the mode of reservation and failure recovery (Failover) is implemented. Failure recovery is an operation mode at which functions of a management system are assumed by a secondary management system in that case when the main system becomes unavailable because of a hardware failure or at the planned idle time. Use of this function increases fault tolerance of a management system. Function of failure recovery in ISaGRAF 6.1 gives the chance to users to modify a management system and to change conditions under which the controller receives or runs away. In the Failover mode the ISaGRAF 6.1 environment implements the following key features: unaccented transition to the reserve machine, work with any POU type (SFC, FBD, LD, ST, 61499), automatic loading of the project (at the same time on primary and secondary station), automatic switching from Workbench to the necessary station in a debug mode, automatic switching of OPC servers. At present support of stored (retain) of variables is not implemented.

Let's consider implementation of the Failover mode in a core of executive system of ISaGRAF. After loading of the application on the active controller its transfer on the reserve controller is automatically executed. Both controllers begin to run the same application in parallel. Input variables are transferred from the main controller to the reserve controller before each cycle of accomplishment. At the end of each cycle check on the calculated checksum is executed to guarantee integrity yielded and results. In case of discrepancy all area of data of the active (main) controller is transferred to the reserve controller. At failure on the active controller the reserve controller becomes active (basic) and begins to manage process. For communication between the main and reserve controller the TCP/IP network is by default used, but also other networks (serial link, UDP, optical fiber) can be used. Setup of a condition under which there is a change of the main controller is allowed. Configuring of Failover consists of installation of the following parameters: IP address, port number and values of timeouts.

Results of testing of the Failover mode by ISaGRAF Inc company.

Test conditions: 85 thousand variables of the user, 4 thousand input variables, the volume of the TIC code is equal 247k, the size of buffers of communication 64k, the main controller works running Windows 7 OS, reserve under control of VMware of Windows XP OS. Results of testing: time of a cycle of 1 ms with the turned-off Failover mode, time of a cycle of 13 ms with the included Failover mode and complete synchronization of data (88102 bytes in 2 frames), time of a cycle of 6 ms with the included Failover mode and partial synchronization of data (4127 bytes in one frame).

Results of testing of the Failover mode on LinPAC controllers (ICP DAS) specialists of FIORD company

Initial data:

• 1. The LP-5131 controller (ICP DAS) – 1 piece.
• 2. The LP-8441 controller (ICP DAS) – 1 piece.
• 3. Executive system of ISaGRAF5 ++ ACE Target
• 4. Development environment of the ISaGRAF Workbench v projects. 6.1.

For check of an option of reservation in the ISaGRAF Workbench v 6.1 application development environment the project and the program where the variable counter on each cycle (200 ms) is incremented was created, the Failover mode is included and values of timeouts are exposed by default.

Loading of the project was performed on primary controller ('Primary Device') then the built-in Failover mechanism transferred a project code to the secondary controller ('Secondary Device') automatically. Each of controllers was in one of three statuses: Running (active), Standby (reserve), Error (error). But in each timepoint one and only one of them was in Running status (active).

Modeling of situations.

Situation 1.

The stop of the secondary controller, its status changes with Standby on Error. Restart of the secondary controller – its status again Standby. Conclusion: At the working primary controller the secondary controller recovers the status after reset.

Situation 2:

Stop of primary controller: the status of primary Running controller changes on Error; the status of the secondary Standby controller changes on Running. Restart of primary controller leads to the fact that the status of primary controller changes with Error on Standby, primary controller becomes reserve. Conclusion: After failure of primary controller the secondary controller becomes the active controller. After recovery or reset of primary controller, the secondary controller remains active until its stop or failure.

Situation 3:

Rupture of physical communication (Ethernet) between controllers without stopping controllers. The status of primary controller from Running passes into Error, the status of the secondary controller passes from Standby into Running.

After recovery of communication between controllers the status of the secondary controller from Running passes into Standby, and the status of primary controller from Error passes into Running. Conclusion: At communication break active is a secondary controller, but after its recovery primary controller becomes active again, and the secondary controller returns to the mode of reserve.

NB. At the moment it is impossible to use in the project at the same time interruptions and Failover.