CONTROLLING AN ONLINE PROCESS IN A PROCESS PLANT

FIELD OF THE INVENTION

The invention relates to methods and systems for monitoring and controlling an online process in a process plant and more specifically for managing analyzers and analytical sub-systems.

BACKGROUND OF THE INVENTION

An online process in a process plant may be carried out using one or more analyzers. The analyzers may be used for performing chemical analysis on samples or sample streams.

In order to use the analyzers, certain configurations may have to be performed. For instance, a background (also referred to as a reference) may have to be configured for an analyzer, wherein the background provides a reference calibration for collecting a measurement using the analyzer. Further, an analyzer may comprise one or more analytical sub-systems or accessories that facilitate in taking the measurement. Accordingly, it may be required to configure the analytical sub-systems (also referred to as accessories) of the analyzers for collecting the measurement.

There are certain issues in the above as analyzers may be provided by various vendors and may have different numbers and types of analytical subsystems (e.g. illuminators, rotating units etc.).

Depending on the vendor of an analyzer, there may be variations in how the background is managed. For instance, the background management may be performed by the vendor. Alternately, the background management may be performed by the Process Control System (PCS) provider. Accordingly, when one desires to use analyzers from different vendors or in a system where there are analyzers from different vendors, there may be a lot of difficulty in setting up the analyzer / analyzers for collecting measurements. There is no general solution about handling of the background management.

Further, when one desires to use an analyzer or multiple analyzers, all the analytical sub-systems need to be available in a desired state for measurements to be accurate. Otherwise the data extracted from the analyzer would not be of the expected quality. Since there may be various analytical sub-systems, which may take different amount of time to start and may also have to be started individually by various operators manually, there may be lot of delays in carrying out the measurements. In addition, there may be various complications in handling of different analytical sub-systems. For example, it is not advisable to frequently start and stop an illuminator. Taking another example, a rotating unit may have to be rotated to place a sample at a particular angle with respect to a light source. There may also be variations in the workflows of various analytical sub-systems. Accordingly, different process control systems may be required for controlling the analytical subsystems.

Current systems and methods fail to address the above-mentioned issues. Accordingly, there is a need for an improved method and system for managing analyzers and analytical sub-systems.

SUMMARY OF THE INVENTION

The invention relates to a system for monitoring and controlling an online process in a process plant. The system allows executing a pre-configured recipe (also called method) which includes the configuration of,

• The analytical system and sub-systems (analyzer, channel, stream, accessories etc.)

• Process variables (e.g. temperature, pressure etc.)

• Chemo-metric models, which perform the prediction of the analyzer data as well the diagnostics on this data The system executes the pre-configured recipe with the following steps:

a. Select the analyzer stream at run-time.

b. Prepare the sub-system,

c. Wait for the notification from the system that the sub-system is ready for acquisition.

d. Send the command for the data acquisition.

e. Processes the data received from analyzer stream using configured Chemo-metric Model.

f. Store the data as well as the predicted property.

Before step d is executed, it is very important that the system has the required background for the specific analytical instrument settings, to be able to calculate the absorbance (scaled data). In addition, it is necessary to have all the analytical sub-systems or accessories ready before step d is executed. If the analytical sub-systems are not in proper state, the acquisition will fail.

An aspect of the invention provides a method and system for monitoring and controlling an online process in a process plant. The system comprises a Process Control System (PCS) for controlling the online process, an analyzer (also referred to as analytical instrument) for collecting a measurement of a process parameter of the online process and an Analyzer Device Integration (ADI) server for facilitating interaction between the PCS and the analyzer.

The method comprises using the PCS for selecting a mode for background management.

The background (also referred to as reference) provides a calibration for the measurement. ADI specification defines the following other terminologies related to the background:

• Pending background: Last acquired background spectrum. This background is not automatically used for evaluation of scaled data until the end user confirms by setting this background as active background. For example, a background may be used to calculate scaled data (also referred to as absorbance) using Abs = - In (S/R), where Abs represents absorbance, S represents the raw data of a sample and R is the background.

• Active background: Background spectrum used for the evaluation of the absorbance. In the case of spectrometer like diode array that requires black and white background, this is the white background.

The OPC UA specification for Analyzer Device Integration (ADI) exist to take the background from the analyzer. But it does not define the way to manage the background. The manage term broadly refers to the storing and retrieval of the background of the analyzer among various analyzer settings.

The management of the background is required so that one does not end up taking the background every now and then. A new background should be acquired depending upon the user requirements but typically here are the use cases in which a user would take a new background:

• When the analytical instrument is used for the first time (In such cases the background is called initial background)

• Any maintenance has been done on the analytical instrument

• When a predefined time (can be referred as background age) has elapsed

• When user feels that a particular measurement is very critical and hence needs a new background measurement

Background management may consist of several operations and may also vary from vendor to vendor. The most common practices are

• Storage / persistence of last known good background in the system (which could be anything from flat file system, SQL database, XML file etc. with a particular analyzer settings.

• Retrieval of last known good background from system for a specific analyzer settings. • Applying last known good background as an active background in the analyzer

• Taken new background from the analyzer as a pending background and applying the same background as an active background to the analyzer either by the PCS or by the vendor managed ADI server

• Defining and managing background age, background validity etc.

In accordance with the method, the mode for background managment may be set based on an identifier associated with the analyzer. Alternately, other analyzer related parameters may be used for setting mode for background management. Further, an operator may use the PCS to set the mode for background management. Alternately, the PCS may be configured to automatically set the mode. The identifier used for setting the mode for background management may be a device identifier or a vendor identifier. In an aspect, in order to set the mode, the identifier is compared with stored information for determining an agreement between a provider of the PCS and a provider of the analyzer for the mode for background management. For example, the PCS and the analyzer providers may agree beforehand regarding who will perform the background managment and such information may be stored in a storage associated with the PCS and/or the analyzer. Further, such information may be linked with the identifier to facilitate the mode selection using the PCS.

The mode may be selected from a PCS managed mode, an analyzer managed mode and a mixed managed mode. In the PCS managed mode, the background management is performed by the PCS. In the analyzer managed mode, the background management is performed using the analyzer by the vendor or provider of the analyzer, and in the mixed managed mode the background management is performed using the PCS and the analyzer.

The method further comprises configuring a background based on a setting of the analyzer for collecting a measurement. The background is configured using the PCS, the analyzer, or both the PCS and the analyzer based on the mode.

The background can be configured by checking the background that is already set in the system. As per the ADI specification, the background that is set in the system is referred to as an active background. The method checks if the active background is valid for the measurement based on an age of the active background. This check may be performed at the PCS or at the analyzer depending on the mode. Further, the check may be performed automatically by the PCS or at the analyzer. Alternately, the check may be performed by an operator by utilizing the PCS and/or analyzer. Other parameters may also be used for checking the validity of the background.

Optionally, the method comprises collecting a new background for the measurement. This may happen if there is no background that is set as the active background. Alternately, this may happen if the background that is already set (i.e. the active background) is invalid. This step may also be performed at the PCS and/or the analyzer based on the mode. For instance, in the PCS mode, the step may be performed using the PCS.

Once the background is configured, the method comprises collecting the measurement using the analyzer. The analyzer collects the measurement based on the background. In one aspect, collecting the measurement comprises determining the availability of an analytical sub-system of the analyzer. For instance, the PCS may be utilized to communicate with the analytical subsystem via the ADI server to determine whether the analytical sub-system is available. The method may also comprise preparing the analytical sub-system upon determining that the analytical sub -system is not available. In one aspect, the PCS sends a signal for preparing the analytical sub-system upon determining that the analytical sub-system is not available. BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the invention will be explained in more detail in the following text with reference to exemplary embodiments which are illustrated in the attached drawings, in which:

Fig. 1 illustrates a simplified diagram of a system for monitoring and controlling an online process in a process plant in accordance with an aspect of the invention;

Fig. 2 illustrates another simplified diagram of the system for monitoring and controlling the online process;

Fig. 3 illustrates a flowchart of a method for monitoring and controlling an online process in a process plant in accordance with an aspect of the inveniton;

Fig. 4 illustrates a flowchart of a method for background management in a PCS managed mode in accordance with an aspect of the invention;

Fig. 5 illustrates a flowchart of a method for background management in an analyzer managed mode in accordance with an aspect of the invention;

Fig. 6 illustrates a flowchart of a method for background management in a mixed managed mode in accordance with an aspect of the invention; and

Fig. 7 illustrates a flowchart of a method for checking availability of one or more analytical sub-systems in accordance with an aspect of the invention.

DETAILED DESCRIPTION

Refering now to Fig. 1 , which illustrates a system 100 for monitoring and controlling an online process in a proces plant in accordance with an aspect of the invention. As illustrated, system 100 comprises a Process Control System (PCS) 102. PCS 102 provides various functions related to controlling the online proces. In accordance with the aspect, PCS 102 assists in selecting a mode for background management (described hereinafter in conjunction with description of Fig. 3). Further, PCS 102 assists in performing background management and collecting measurements.

PCS 102 may be accessible via a client 104 such as, but not limited to, a desktop, a laptop etc. Further, PCS 102 may comprise a storage (not illustrated). Alternately, PCS 102 may be connected with an external storage such as 106. The storage can store various information that can be used for carrying out the online process in the process plant. In addition, PCS 102 may comprise an execution engine (not illustrated) that assists in carrying out one or more methods of the online process. Further, PCS 102 may comprise various modules (not illustrated) that assist the execution engine in carrying out the one or more methods. Such modules can be a method configuration module, a model setting module, an analyzer setting module, a process values model and so forth.

System 100 also comprises one or more Analyzer Device Integration (ADI) servers such as, but not limited to, an ADI server 108a, an ADI server 108b and an ADI server 108c. An ADI server can be part of a vendor system that has properties (e.g. namespace) descibed by the vendor. Further, the ADI server should be such that it can be accessible via PCS 102.

Each ADI server facilitates interaction between PCS 102 and a corresponding analyzer of system 100. For example, ADI server 108a facilitates interaction between PCS 102 and an analyzer 110a. Similarly, ADI server 108b and ADI server 108c facilitate interaction between PCS 102 and an analyzer 110b and an analyzer 110c respectively.

An analyzer (also referred as analytical instrument) can be used for collecting a measurement of a process parameter of the online process. Each analyzer of analyzer 110a, analyzer 110b and analyzer 110c collects a measurement of a process parameter of the online process. System 100 may include a single analyzer or multiple analyzers (as illustrated in Fig. 1 and Fig. 2). The measurements collected from the analyzers of system 100 are provided to prediction server 112 by PCS 102. Prediction server 112 may utilize one or more models such as, but not limited to, chemo-metric models, for processing the measurements collected from the analyzers. The measurements can be processed for one or more of, but not limited to, diagnosis and prediction.

Each analyzer of system 100 comprises one or more analytical streams. Each of the one or more analytical streams comprises one or more channels. Each of the one or more channels comprises one or more slots. One or more analytical sub-systems such as, but not limited to, an analytical sub-system 114a, an analytical sub-system 114b, an analytical sub-system 114c, and an analytical sub-system 114d may be connected with the analyzers of system 100 as illustrated in Fig. 2. For example, two analytical sub-systems may be connected with one analyzer (e.g. 114a and 114b) or a single analytical subsystem may be connected with one analyzer (e.g. 114c and 114d). An analyical sub-system assists an analyzer in collecting measurements. For instance, an anlaytical sub-system can help in one or more of improving the quality of data and provide additional data to be used in process control. An example of an anlytical sub-system is an illuminator, which may be used to provide adequate light while collecting a measurement for a sample. Taking another example, a rotating unit may be utilized to place a sample at a particular angle with respect to a light source for collecting a measurement.

Referring now to Fig. 3, which illustrates a flow chart of a method for monitoring and controling the online process. At 302, a mode for background managment is selected. The mode of background management can be selected from a PCS managed mode 304, an analyzer managed mode 306, and a mixed managed mode 308 (described in detail in conjunction with description of Fig. 4, Fig. 5 and Fig. 6).

In one implementation, the mode is selected by an operator of system 100. In another implementation, the mode is selected by PCS 102. The mode is selected based on an identifier associated with a corresponding analyzer of system 100. For example, if there is one analyzer (e.g. 110a), an operator can select the mode based on an identifier of that analyzer. The identifier may be a device identifier or an identifier of a vendor of the analyzer. The identifier can be compared with information already available with PCS 102 and/or the operator to determine an agreement between a provider of PCS 102 and the analyzer (110a) regarding the mode for background management. Taking another example, where there are multiple analyzers. In this case, the identifiers of each of the multiple analyzers can be analyzed to determine the mode for background management for each of the multiple analyzers. Here, it is possible, that each analyzer may have a different mode for background management (e.g. analyzer 110a in PCS managed mode, analyzer 110b in analyzer managed mode and analyzer 110c in mixed managed mode).

In an aspect, background age configuration and management is done only by PCS 102. In accordance with this aspect, a vendor of any of the one or more analyzers has no control over the background age configuration and management.

Once the mode for background management has been selected, a background is configured for each analyzer that is used for collecting a measurement. For example, when one analyzer is used, the background is configured for that analyzer. Taking another example, if three analyzers are used, then for each of the three analyzers a background is configured.

Depending on the mode for background management, the background is configured using one or more of PCS 102 and one or more analyzers of system 100.

Once the background is configured, the measurement is collected using the one or more analyzers of system 100 at 312. In an aspect, before the measurements are collected, PCS 102 checks for availability of each analytical sub-system of system 100 (described in detail in conjunction with description of Fig. 7). Further, PCS 102 enables the measurement if all the analytical subsystems are available. The measurement can then be sent to prediction server 112 for processing.

Refering now to Fig. 4, which illustrates a flowchart of a method for background management in PCS managed mode 304. In PCS managed mode 304, the entire responsibility for background management is at PCS 102. This may be handled by one or more of a provider, an owner and a user of PCS 102. Further, a vendor of an analyzer of the one or more analyzers for which PCS managed mode 304 is selected, does not take any responsibility for the background management in PCS management mode 304.

Initially, PCS 102 stores backgrounds corresponding to analyzer settings in a storage such as storage 106. Thereafter, whenever a measurement with a particular analyzer setting is requested, the corresponding background is identified and set as active background by PCS 102.

The method starts with PCS 102 first checking the mode for background management. If it is PCS management mode 304, then at 402, PCS 102 will check if a background is available for the analyzer setting for which the measurement has to be collected.

If a background is available, then PCS 102 checks the validity of the background at 404. In one implementation, for checking the validity, PCS 102 retrieves the background validation related configuration settings defined in a configuration sub-system associated with PCS 102. To check the validity of the background PCS 102 checks if the persisted background timestamp is compliant against the background age configured in the configuration subsystem of PCS 102. If the background has expired, then PCS 102 directs the user of PCS 102 to collect a new background. If the background has not expired, then PCS 102 performs a validation for the background settings. If the background settings are valid, then PCS 102 retrieves the background from the storage and sets this as the active background at 406. Once set, the background may be used to calculate scaled data (absorbance). For example, the background may be used to calculate absorbance using Abs = - In (S/R), where Abs represents absorbance, S represents the raw data of a sample and R is the background.

If at 402, PCS 102 determines that a corresponding background is not available or if PCS 102 determines that an available background is not valid, then at 408, PCS 102 directs the user to collect a new background for the measurement according to the analyzer settings. Thereafter, the user (e.g. an owner, provider or administrator of PCS 102) collects the new background from the analyzer and provides the new background. Optionally, at 410, the new background is passed through a validation routine. For instance, the background may be passed to diagnostic models (e.g. chemometric models). If at 412, the background is found to be invalid, then PCS 102 again directs the user to collect a new backgound. Otherwise, PCS 102 sets the new background as active background at 406. The active background may also be stored as the last known good background in the storage along with the analytical instrument settings. Subsequently, the analyzer can be used for collecing the measurement as per the active background.

Referring to Fig. 5, which illustrates a flowchart of the method for background management in analyzer managed mode 306. In analyzer managed mode 306, the entire responsibility for background management is at analyzer (e.g. the analyzer for which analyzer managed mode 306 is set). This may be handled by one or more of a provider (e.g. vendor), an owner and a user of the analyzer. Further, PCS 102 is not allowed to set the active background in the ADI server in this mode.

In accordance with the method, PCS 102 firstly checks if the mode for background management is analyzer managed mode 306. If it is analyzer managed mode 306, then PCS 102 obtains the configuration settings defined in the configuration sub-system and applies the configuration settings to the vendor's ADI server. Once the configuration settings are applied, at 502, the vendor's ADI server will check if the last known good background corresponding to this configuration settings exists in an associated persistent storage. If a background exists, then the vendor's ADI server applies this background as an active background in its namespace at 506. Once set, this background may be used to calculate the scaled data (absorbance).

If however, the vendor's ADI server does not find a corresponding background, then an empty background will be applied as active background.

Prior to setting of the active background, PCS 102 at 504, checks if the active background's (provided by vendor's ADI server) timestamp is compliant wiht the backgroud age configured in the configuration sub-system of PCS 102. If the background is expired, then PCS 102 directs the end user to collect a new backgroud. Further, additional validation checks such as background diagnostics may be applied on the acive background provided by the vendor's ADI server. If the background diagnostics does not provide good results, then also PCS 102 may direct the end user to collect a new background.

If a background is not available in the storage or if a background provided by the vendor's ADI server is not valid, then at 508, PCS 102 directs the end user to collect a new background. In the case, the vendor collects a new background for the measurement as per the analyzer settings. Optionally, at 510, the new background is passed through a validation routine. For instance, the background may be passed to diagnostic models (e.g. chemometric models). If at 512, the background is found to be invalid, then PCS 102 again directs the user to collect a new backgound. Otherwise, the new background is set as active background at 506. The active background may also be stored as the last known good background in the storage along with the analytical instrument settings at the analyzer side. Subsequently, the analyzer can be used for collecing the measurement as per the active background.

Referring to Fig. 6, which illustrates a flowchart of the method for background management in mixed managed mode 308. In mixed managed mode 308, the background management is handled by both PCS 102 and vendor system (e.g. vendor's ADI server). Here, vendor system is responsible to store and retrieve the background along with corresponding analytical instrument settings whenever applicable from an associatd persistent storage. However, the vendor system does not write the background to the active background. This means, till the user of PCS 102 does not find the collected background as suitable (either by visible inspection or by way of diagnostic models), PCS 102 will direct the user of the vendor system to keep collecting a new background. Once an acceptable background is identified, PCS 102 writes that background as the active background to the vendor's ADI server.

In accordance with this method, initially PCS 102 checks the mode for background management. If it is mixed managed mode 308, then PCS 102 obtains the configuration settings defined in the configuration sub-system and applies the configuration settings to the vendor's ADI server. Once the configuration settings are applied, at 602, the vendor' s ADI server will check if the last known good background corresponding to this configuration settings exists in an associated persistent storage. If a background exists, then the vendor's ADI server applies this background as an active background in its namespace at 606. If the active background in the vendor's system is empty, then PCS 102 directs the user of the vendor system to collect a new background.

If the active background in the vendor's system is not empty, then at 604, PCS 102 checks if the active background's timestamp is compliant with the background age configured in the configuration sub-system of PCS 102. If the background has expired, then PCS 102 directs the user of the vendor system to collect a new background.

If a background is not available in the storage or if a background provided by the vendor system is not valid, then at 608, PCS 102 directs the user of the vendor system to collect a new background. The user collects a new background for the measurement as per the analyzer settings. Optionally, at 610, the new background is passed through a validation routine. For instance, the background may be passed to diagnostic models (e.g. chemometric models). If at 612, the background is found to be invalid, then PCS 102 again directs the user of the vendor system to collect a new backgound. Otherwise, the new background is set as active background at 606 by PCS 102. The active background may also be stored as the last known good background in the storage along with the analytical instrument settings at the analyzer side. Subsequently, the analyzer can be used for cohering the measurement as per the active background.

Referring to Fig. 7, which illustrates a method for checking availability of one or more analytical sub-systems in accordance with an aspect of the invention. As mentioned in the description of 312 above, prior to collecting the measurement, PCS 102 may optionally check for the availability of the analytical sub-system (or sub-systems) of the corresponding analyzer (or analyzers).

In accordance with the method, at 702, PCS 102 upon receiving an input for collecting the measurement checks if all the analytical sub-systems are available. For example, a user of PCS 102 can trigger a measurement at an analyzer. Accordingly, PCS 102 checks if all the analytical sub -systems of the corresponding analyzer are available. This check can be perforrmed by sending a communication from PCS 102 to each connected analytical subsystem. Alternately, each analytical sub -system can provide a notification at a corresponding slot of the analyzer, which can be read by PCS 102.

If PCS 102 determines that all the analytical sub-systems are available for collecting the measurement, then at 704, PCS 102 indicates that the measurement can be performed. Further, the analyzer can be operated (e.g. by PCS 102 directly upon the determination) for collecting the measurement.

If PCS 102 determines that one or more of the connected analytical subsystems are not availabe, then at 706, PCS 102 sends a signal to the corresponding analytical sub-systems for preparing all the analytical sub- systems. In addition, at 708, PCS 102 subscribes for a ready signal from each analytical sub -system (or at least the analytical sub -systems that are not avaialble yet). Subsequently, at 710, PCS 102 periodically checks for availability of all the analytical sub-systems. If all the analytical sub-systems are available, PCS 102 proceeds to 704 indicating that the measurement can be performed. Further, the analyzer can be operated (e.g. by PCS 102 directly upon the determination) for collecting the measurement. If the analytical subsystems are not available, then at 712, PCS 102 waits for a certain period before checking for availability of each analytical sub-system. It is possible to provide a notification that the measurement cannot be performed if any of the required analytical sub-systems are not available (in the first check or after a predetermined number of checks or time period).

In one aspect of the invention, it is assumed that the vendor of the analyzer has implemented the ADI specification and an ADI server such that a generic client can be developed by PCS 102 vendors. In accordance with the aspect, the invention would allow controlling the analytical sub-systems / accessories using two properties in the process control system. These two properties are named "Prepare" and "Is Ready". The first property "Prepare" allows starting / preparing the sub-system. Preparing involves one or more operations that can be performed in the sub-system depending on what is desired to be performed in the system/sub-system. For example, an accessory which starts the internal cooling can start the cooling when the "Prepare" property value is set to true. When the temperature comes down to a particular preset, it marks the "Is Ready" to true. This means the "Is Ready" indicates if the desired state / status of the sub-system is achieved and that the sub-system is ready to perform the intended operation.

Depending on the analytical sub-system, there may be certain variations in the start-up process of the analytical sub-system. Consider a scenario where the analytical sub- system is an illuminator, which is a device that provides illuminattion in a particular frequency range. When a measurement is to be collected, the illuminator needs to be started. It takes a few seconds for the illuminator to get started. Therefore, the acquisition should be executed only when the illuminator is stable. There are certain constraints while using an illuminator. It is not advisable to frequently start and stop the illuminator else the lamp of the illuminator may get damaged. If the illuminator is not stable, the acquisition request should be rejected. PCS 102 should be able to determine if illuminator is ready for the measurement as opposed to PCS 102 polling the illuminator each time a measurement is required. The end user should switch off when the illuminator is no more in use.

In accordance with the scenario, the user of the illuminator can set a status of the illuminator as not available or "Prepare" only a few times a day. PCS 102 accordingly sets an equivalent operation in the vendor's ADI server. Further, PCS 102 can subscribe for a notification status such as "Is Ready" so that it gets to know about the availability of the illuminator as soon as it is ready.

Consider another scenario where the analytical sub-system is a rotating unit which when prepared, makes a complete rotation of the container (as per the configured speed). Further, when the sample comes in a particular angle of the main light source of the instrument (angle is also configured with threshold), the acquisition should be performed. There may be certain constraints in operating the rotating unit. For example, the rotating unit needs to be started (Prepare) every time the acquisition to be performed. Further, if the light source is not in a threshold angle, the acquisition request should be rejected. PCS 102 should be notified when the sample is in a threshold angle of the light source (e.g. notification of "Is Ready" = "True") rather than PCS 102 polling the rotating unit each time a measurement is required. Further, the illuminator may also be required in addition to the rotating unit. Accordingly, the condition of both the sub-systems should be satisfied before an acquisition is performed. In case of the rotating unit, the end user sets the "Prepare" property value to true each time an acquisition is requested. This is a frequent operation and each time prepare is set, PCS 102 shall set the equivalent operation in the vendor's ADI server. The unit will rotate at a predefined speed and once the desired angle is achieved, the vendor ADI server system will set the "Is Ready" to true. Once the acquisition is done, the ADI server will set "Is Ready" to false so that end user can control it for the next acquisition.

In case the sub-systems perform an auto prepare, i.e. they do not expect the external system to send a prepare command, the subscription to the "Is Ready" will be sufficient. The prepare command may be ignored in such cases. User actions can also be set by using an external control system (e.g. controller logic, sensor output, batch application etc.).

Thus the sub-systems are controlled with manual user interaction or the controller logic, but the application level logic will be generic for all the subsystems of the analytical system.

The invention provides the following advantages. A single process control system can manage multiple analyzers and analytical sub-systems. Further, a single process control system can manage different vendor's background management workflows. Since the system supports controlling multiple vendor's background management workflows, the system is interoperable. Customers using one vendor's analytical instrument and ADI Server application can easily migrate to other vendor's analytical instruments and ADI server application using a single ADI compliant process control system. The process control system can support more than one vendor's analytical instruments and analaytical sub-systems simultaneously during an online measurement. The process control system supports configuration of different background age for different analytical instruments. The process control system also supports the diagnostic model execution from different chemo- metric vendors. Maintenance is easier as it is easy to deal with a generic solution in the process control system.