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Maintenance Station – User interface for maintenance
The SIMATIC PCS 7 Maintenance Station software package is available as an alternative to SIMATIC PCS 7 for imple- menting Plant Asset Management. You can use this soft- ware package to expand an Operator Station to a Maintenance Station.
The maintenance engineer can process the diagnostics messa- ges and maintenance requests of the assets on the Maintenance Station. Via the Maintenance Station the engineer can access:
•Electronic components of the process control system: intel- ligent field devices and I/O modules, field bus, controller, network components and plant bus as well as servers and clients of the operator systems.
•Mechanical components that do not belong directly to the process control system such as pumps, motors, centrifu- ges, heat exchangers or control loops (passive or indirect assets). These are represented by proxy objects in which the diagnostics rules are stored.
Monitoring and diagnostics of mechanical components
Exceeding the limits of the pump's rated operating range and deviations from the anticipated characteristic curve are repor- ted to the user as maintenance alarm via the PumpMon block. The block outputs are simultaneously made available for further processing. In this way, the user gets the opportunity to intervene in a preventive way to prevent damage to the pumps, which helps to reduce plant downtimes and increase its availability. It also allows the pump layout to be optimized.
For mechanical components without
Pump monitoring with the block PumpMon
The diagnostic block PumpMon is used for
•Warning of pump damage when there is blocking, dry run- ning, gas in the transported substance, cavitations, over- load, or improper running;
•Early detection of initial pump damage, such as wear or de- creasing pump efficiency;
•
PumpMon block: Transport characteristic curve with current operating point
Valve monitoring with the block ValveMon
Abrasion, cavitation, corrosion of the valve plug or seat as well as caking (fouling, deposits) are the most common signs of wear for valves. ValveMon monitors the valve status according to specific process values and enables the detection of mal- functions and impending failures at an early stage.
Heat exchanger monitoring with the block HeatXchMon
The main problem with heat exchangers is fouling. Fouling re- sults when residues of the process medium are deposited on the transfer surfaces and thus impair efficiency. HeatXchMon determines deviations of the current heat flow from the refe- rence heat flow in the clean state. The current degree of fou- ling, the energy loss and daily costs can thus be precisely cal- culated and displayed.
The HeatXchMon block not only indicates the current performance capa- bility of the heat exchanger, it also calculates the daily energy loss due to the degree of fouling.