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Siemen’s Maintenance Station supplements Simatic PCS7 to provide a valuable instrument for asset management
The Maintenance Station integrated in SIMATIC PCS 7 process control system provides a complete status overview of all plant components and offers an effective diagnostics, service and maintenance of the plant. The SIMATIC PCS 7 Maintenance Station maximises the economic value of the plant assets by helping you reduce unplanned downtime and efficiently use maintenance investment. If one considers the total maintenance involved in an enterprise then the Maintenance Station is focused on the area of plant asset management. Asset management for plant engineering is the administration and management of plant equipment, particularly industrial and commercial (I&C) equipment, as well as all activities and measures that serve to retain or increase the value of a plant. This includes the following maintenance strategies: Corrective maintenance: In response to existing fault and diagnostics messages
Failures are risked by redundant configurations Maintenance is undertaken in the form of repair or replacement Preventative maintenance: Preventative diagnostics and maintenance of equipments Appropriate maintenance measures are initiated before a fault even occurs Maintenance in the form of timedependent or status-dependent maintenance (dependent on degree of wear) Predictive maintenance: Predictive diagnostics for timely detection of potential problems and to determine the remaining service life While the plant operator obtains all relevant information that is necessary for focused intervention in a process via the operator system, maintenance and service personnel can check the hardware assets and process their diagnostic messages and maintenance requests from the Maintenance Station.  For this the Maintenance Station offers access to: Components of the process control system: intelligent field devices and I/O modules, fieldbus, controller, network components, and plant bus, as well as servers and clients of the operator systems. Assets that do not belong directly to the process control system, such as pumps, motors, centrifuges, heat exchangers or control loops. These are represented by proxy objects in which the diagnostics rules are stored. Maintenance cycle The status of all components or of a device can be determined by monitoring (acquisition and analysis of process values and status values). For example, if a sensor no longer delivers a signal, the diagnostics function indicates that there is an open circuit. This triggers a maintenance request which in turn results in a maintenance measure. Following completion of maintenance the status displays are reset to the normal status on the maintenance station. The complete maintenance cycle is documented on the Maintenance Station without gaps— automatically and without additional configuration overhead. Architecture Depending on the project-specific Simatic PCS 7 architecture, the Maintenance Station can be implemented on the basis of a Simatic PCS 7 BOX RTX/416, a Simatic PCS 7 Single Station, or on the basis of a client-server combination. For asset management, it uses hardware and software components from the engineering system (ES) and operator system (OS).
As a result of the close interlacing, the ES, OS, and asset management functions execute on common hardware. Such a multifunctional station cannot only be used for asset management, but also for system engineering or HMI. The message system, GUI, display hierarchy and operator prompting are oriented according to the HMI philosophy of the operator system. The diagnostics data of all assets is displayed on uniform faceplates.This means that working with the maintenance station is simple and intuitive, complex familiarisation is not required. The diagnostics displays structured according to the plant hierarchy with the operating states of all Simatic PCS 7 components can be displayed on the maintenance station and also on an OS client. However, enhanced online diagnostics functions in conjunction with HW-Config or Simatic PDM , and can only be called from the maintenance station. The user management and access control for the maintenance station accept the Simatic Logon integrated in Simatic PCS 7. Configuration The Simatic PCS 7 asset management is based on the hardware and software project of the application, which is generated during the standard configuration with the engineering system. With system support, all data relevant to asset management is derived from the project data of the application, and the diagnostics displays are also generated, simply by pressing a button. The procedure is simple, and no additional overhead is required for the asset management. It is composed as follows: Generation of the hardware and software project of the application System-supported generation of the diagnostics displays with all components present in the project, including the display hierarchy according to the project's hardware structure Compilation of the configuration data, and downloading to the operator station and maintenance station with subsequent test and commissioning phase. Conformity to international standards, specifications, and recommendations Simatic PCS 7 Asset Management with the Maintenance Station conforms to international standards, specifications, and recommendations. Simatic PCS 7 asset management takes into account the Namur requirements (process control standards committee in the chemical and pharmaceutical industries) defined for systems for asset management at plant level and for status messages from field devices: Namur recommendation NE91 (requirements for systems for asset management at plant level) Namur recommendation NE105 (requirements for the integration of fieldbus devices in engineering tools) Namur recommendation NE107 (status messages from field devices): “Device failure”, “Maintenance requirement”,“Function check”). In addition, it follows the IEC 61804-2 for describing devices by means of the Electronic Device Description Language (EDDL) and specifications made by the Profibus and Profinet International (PI) organisation: Profibus Profile Guidelines Identification and Maintenance Functions Profibus PA Profile for Process Control Devices. Asset Management function characteristics As the system interface for the maintenance organisation, the Maintenance Station with the integrated asset management software makes consistent maintenance functions and information available. Standard diagnostics functions. In order to obtain information on the diagnostics status of individual plant areas or components, maintenance engineers can change from the overview display to the respective diagnostics display of the subordinate hardware level. If a fault is signalled in the overview display, the ‘loop in alarm’ function permits rapid switching to the diagnostics faceplate of the associated component. The information is filtered according to the area of responsibility of the user. The following information can be offered: Display of diagnostics status determined by the system Information on the component, such as process tag name, manufacturer or serial number Display of diagnostics messages of a component Visualisation of type and current state of initiated maintenance measure. Information on passive or indirect assets For passive or indirect assets without self-diagnostics (pumps, motors, control loops, etc.), inadmissible operating states can be derived from various measured values and their deviations from a defined normal status using the programmable logic block AssetMon. These are displayed as a maintenance alarm on the maintenance station. With the aid of the AssetMon, individual diagnostics structures, projectspecific diagnostics rules and condition monitoring functions can be implemented.  Extended information for assets according to IEC 61804-2Additional information can be called for assets described by the electronic device description (EDD) according to IEC 61804-2. This information is automatically read out from the components and made available by Simatic PDM in the background. Detailed diagnostics information: Device-specific information from the vendor, information on fault diagnostics and troubleshooting Results of internal conditionmonitoring functions Status information (eg changes in local operation, local configuration) Display of modification logbook (audit trail) of the component with all entries on the persons, times and types of operator intervention on the component Parameter view of the assets (display of parameters saved in the component and in the project; if required, also differences between them). Conclusion The Maintenance Station is based on the Plant Asset Management and enables preventive and predictive diagnostics, service, and maintenance of the production plant. In parallel with process control, the Maintenance Station makes available consistent maintenance information and functions for all system components (assets).
The Maintenance Station not only provides the information that a fault exists but provides detailed guidance to the maintenance personnel so that necessary corrective or preventative action can be performed. Courtesy: Siemens |
