Plant Liqu iT enhances Plant Direct iT with the option of mapping entire technical processes in sequences. Each sequence is a class instance with fully configurable parameters in terms of the defined steps, functionality within these steps and their transitions (branching points and step enabling conditions). When engineering the step-internal functionality, already defined objects (e.g. valves, measuring points) and, in particular, the process-related class OCM (Object Control Matrix) are used.
Plant Liqu iT classes which have been specifically tailored to the beverage industry (e.g. FIFO for handling queues and automatic tank changes) complete the basic functionality of Plant Liqu iT and enable the parameterisation of entire process sequences.
Each sequence can be monitored in detail via a separate operating dialogue and, if necessary, also controlled. An online view of the transitions of each sequence allows extensive analyses and direct intervention in the process sequence. All relevant events and data, including possible interventions, are recorded and subsequently available in a detailed sequence record for later checks and documentation purposes.
During operation, an efficient sequence overview provides a precise overview of all the plant sequences and their current status at any time. If irregularities occur, the operator can intervene directly from this overview.
Particularly for plants where a wide range of products and semi-finished products are produced using the same or similar process sequences, Plant Liqu iT offers a special functionality for recipe-controlled processes based on a simplified procedural model. Process sequences are described as procedures, consisting of one or several sub-procedures which in turn include one or several operations.
Each sub-procedure equals an instance of the “sequence” class and the steps defined for this instance represent the operations. By combining this type of procedure with various parameter sets of the same structure, it is possible to generate master recipes, e.g. for producing various products with the same procedure. The system differentiates between recipe and equipment parameters. Various replacement methods are available for the recipe parameters; these methods specify for each parameter whether it should be treated as a constant with regard to a recipe or can be individually specified at the beginning of a process sequence. Equipment parameters describe technical properties of the plant and are thus generally treated as constants.
For multi-product plants with a network structure, Plant Liqu iT enables the complete parameterisation of the usually complex mapping of various routes which might have to be selected depending on the product. This considerably facilitates operation and system adaptations for modifications, extensions or procedure adjustments. A special equipment module, the REM (Route Equipment Module), in connection with OCM objects enables the parameterisation of a fully automatic route control. The sequence addresses a variable number of REM objects which can be allocated to it either statically (technically determined routes) or dynamically (source, target or product-dependent routes). Depending on the part routes or plant sections to be used, each REM addresses statically or dynamically allocated OCMs which check the actuator and sensors allocated to them.
Especially for mapping processes with a high number of source/target combinations, Plant Liqu iT offers two efficient tools for handling tank farms - the Tank Farm Wizard and the Tank Farm Overview. The Tank Farm Wizard provides parameterisation help, enabling the parameterisation of complex tank farms, including the permissible route combinations and interlocks. Adaptations in case of extensions or modifications can thus be planned easily and accurately. The Tank Farm Overview offers a detailed multi-layer online view of the current statuses of the entire tank farm, a tank group or a single tank. All the key parameters (e.g. filling quantity, cleaning status, current order) and the currently executed process steps (e.g. filling, emptying, cleaning) are presented in a clear and concise manner. If irregularities are detected using the tank status display, the operator can access the operating dialogues of the respective tank directly from the overview of the process image.
Plant iT material, the system component for process-related materials management, can be accessed directly from the process control. Transaction-accurate booking records can be created for each individual material transaction more or less in real-time from the current process via system-internal standard functions. This enables material-related process control including inventory management and – combined with superordinate order management – batch tracing.
The equipment modules further increase the efficiency and accuracy of automated process sequences. These special technological classes encapsulate the process functionality of complex technical equipment or entire plant sections, ensure their reproducibility and offer simple and safe operation of complex process functions via the class-inherent operating dialogue in manual or semi-automatic mode.
Equipment modules have been optimised for sequences, but can also be used with any other class. The available modules range from simple applications (e.g. temperature control of a fermenter or fermentation tank) to function encapsulation of complex equipment (e.g. raking system of a lauter tun) or entire plant sections (e.g. malt transportation system).
In order to improve analyses, the operating dialogue of an equipment module provides a special online overview of its communication with the objects which are also involved in the control of the same process.