CEMView Data Acquisition System
CEMView is a family of Modular, High Performance Data Acquisition and Reporting Software for Environmental and Continuous Emissions Monitoring.
Hence, the requirements for a robust application architecture is always at the forefront of the CEMView design requirements.
Developed specifically for environmental monitoring applications, the open, modular and scalable architectures highly flexible and configurable. It is simply the best solution to your needs for a robust CEM DAS.
The view that the CEM system is a separate standalone system which must exist on the periphery of the plant process control system, operated by the environmental personnel and not the process control personnel, in our opinion, is rather antiquated.
The Nexus Solutions vision for the CEM system is that it is simply an extension of the overall plant process control system. It should fit seamlessly into, and simply be an integral part of the architectural backbone of the plant process control system.
The result of our unwavering commitment to product excellence is that the CEMView product family has set the standard and continues to raise the bar for a CEM DAS.
The design philosophy of CEMView is to ensure that you always know everything you need to know…
from any place
from any location
CEMView is designed to simply be the best. A number of world class open technologies and features incorporated into CEMView help to make CEMView the standard for a CEM DAS.
A robust application architecture is the foundation of any great product. The CEMView application architecture meets this challenge head-on by incorporating the OPC Specification standards, the most important open standard for process control systems to have emerged in decades.
The CEMView Environmental and Continuous Emissions Monitoring Data Acquisition System (CEM DAS) is a three-layered application architecture that allows for a highly flexible, modular, scalable and configurable information management system. It is structured to meet the most demanding application requirements and to support future applications. The three logically distinct software application layers are:
Adherence to open industry standard specifications simplify integration of the CEM DAS with current and future plant process control architectures. These technologies also ensure that CEMView can meet and exceed the regulatory compliance reporting requirements for all applications. The CEMView OPC based architecture was an industry first and the technological advantages of the CEMView architecture has proven to be the new standard for process control architectures.
Advanced instrument diagnostics are crucial to operating and maintaining the CEM system and to ensure that overall system availability is maximized. The CEMView diagnostic capability seamlessly integrated into the product is unparalleled in the industry.
The scalable CEMView architecture also ensures that a version of CEMView exists to meet the application compliance requirements and at the same time to offer the best value. Several CEMView versions and configurations are available to suit a spectrum of needs. Additional features include High Availability, Data Mirror, Data Buffer-PAC and a version specifically designed for Stack Testers
Traditional CEM DAS systems interface to the analysis instruments using a CEM data logger or a traditional PLC. How does CEMView acquire data from the analysis instrument and how is this different from a traditional CEM data logger?
CEMView connects directly to the analysis instrument using the serial RS-232/422/485 or Ethernet connection and an instrument specific OPC Server. It communicates directly with the analyzer to acquire the measured pollutant information. There is no analogue signal drift of the data values using this technique.
The CEM data logger or the traditional PLC interface with the analysis instrument’s analogue current (4-20 mA) or voltage (0-10 VDC) signals that represent the measured pollutant. There is no way to eliminate the analogue signal drift of the data values inherent in using this technique.
Analogue signal drift of the analyzer output signal digital-to-analog (D/A) conversion process and the data logger input signal analog-to-digital (A/D) conversion process are an unavoidable fact-of-life. The bit resolution of the D/A and A/D converters also contribute directly to magnitude the signal drift. The lower the bit resolution, the higher the discrepancy, hence, expensive 16-bit resolution D/A and A/D converters should be used. Often with some inexpensive PLC models, 16-bit analog input modules are simply not available.
Additional benefits of the direct connection to the analyzer include advanced instrument diagnostic and parameterization capability that is simply not possible with the traditional legacy discrete and analog signal interconnect of traditional data logger and PLC based approaches.
Reliable computer hardware is also a cornerstone of any robust CEM DAS. Nexus Solutions has a number of standard computer hardware configurations that incorporate several important features such as a RAID 1 mirrored drive array mounted in vibration isolation drive bays, which ensure reliable operation in industrial process control environments.
A data logger or a PLC is effectively a single board computer (SBC) which is housed in an industrially hardened chassis or enclosure. If the data logger or PLC fails, it must be fixed or replaced.
Nexus Solutions offers more than just one choice as a solution to the needs for a robust CEM DAS. With CEMView, this need is balanced with the advantages of directly communicating with the instrument and the inherent benefits that arise in diagnosing and fixing problems with the analyzers of the CEM system. With a data logger or PLC, advanced instrument diagnostics are simply not available to the CEM DAS. Our solutions include:
The High Availability CEMView system is available for applications that require the CEMView DAS to be always available. The redundant system is more than just two computers running the CEMView application in parallel. As a redundant system, it is designed to handle numerous failure modes with automatic failover and recovery capability.
The CEMView Data Buffer Programmable Automation Controller (DB-PAC) is a single board computer (SBC) with a Windows Embedded operating system. This is effectively equivalent to a data logger or PLC and it communicates directly with the instrument.
Finally, the typical CEMView PC that Nexus Solutions strongly recommends is greatly enhanced to increase robustness. It contains a RAID 1 mirrored solid state drive (SSD) array: solid state drives are now standard.
True, if the PC which CEMView is running on fails, then it must be fixed or replaced. But then again, if the data logger or PLC fails, it too must be fixed or replaced.
CEMView Product Family
The CEMView product family can be custom tailored to meet the regulatory compliance requirements of even the most demanding applications.
CEMView is available in several different versions and languages to meet the regulatory compliance requirements for a number of jurisdictions and countries. Additional information and details are also available at this link to our CEMView Versions.
Please consult us if you are unsure of which version of CEMView is suitable for your application. Your country, jurisdiction and industry-specific application requirements determine which version of CEMView is best suited for your site specific needs for a CEM DAS.
CEMView is a UNICODE application and it is currently available in several languages including English, French, German, Spanish, Chinese, Arabic and Russian. Translation to any other language is possible.
Advanced Instrument Diagnostics
CEMView is designed with diagnostics in mind…
CEMView takes advantage of the direct communication interface with the analysis instrument to bring advanced instrument diagnostics to the CEM DAS. With CEMView, it is possible to have a comprehensive CEM system that includes complete software control, configuration parameterization and diagnostics for every analysis instrument of the CEM system.
There is no limit to amount of diagnostic information from an instrument which can be made available in CEMView. Because CEMView interfaces to the analyzer using an instrument specific OPC Server, complete instrument data and status information can be acquired using the communication link. The information can be made available in CEMView itself, to optional CEMView add-on diagnostic, configuration and parameterization software or to any other OPC Client software application via the OPC Data Access and OPC Alarm and Events specification interfaces of the OPC Server.
Context sensitive on-line help is a natural extension of the diagnostic information acquired from the instrument. CEMView allows the user to link the diagnostic status flags to the instrument’s electronic user manual, on-line help files, Adobe Acrobat pdf files or even a URL hyperlink to an intranet or internet web server.
For the Sick Maihak products, the Sick MEPA configuration application products can be added seamlessly to the CEMView system to function as an integral part of the CEMView application.
CEMView Connectivity Options
The CEMView open, modular and scalable architecture is designed for seamless integration with existing and future plant and process control architectures and networks. A number of industry standard open connectivity technologies and solutions are available to integrate CEMView with plant and process control systems.
Connectivity to an analyzer instrument or sensor
CEMView is capable of communicating directly with an analyzer instrument using an instrument specific OPC Server.
For analog (4 – 20 mA, 0 – 10 VDC, etc.) and discrete voltage (24 VDC, 120 VAC, etc.) signals, an I/O sub-system is used. CEMView uses the appropriate OPC Server (Modbus, RS-Linx, etc.) to communicate with the I/O sub-system.
Connectivity to a DCS or PLC-based process control system
CEMView is capable of interfacing with a DCS or PLC process control system using a variety of connectivity options.
Connectivity to process control systems is accomplished using:
- An I/O subsystem for traditional analog and discrete I/O. For example, Schneider Electric’s Advantys STB and OTB Modular Distributed I/O Platform.
- Nexus OPC Client Modbus Slave Link Gateway for Modbus Slave TCP or ASCII/RTU communications
- An OPC Server for the specific DCS or PLC process control system.
CEMView OPC Server capability for OPC Client enabled process control systems.
Connectivity to corporate Environmental Health and Safety (EHS) or Data Historian systems such as SAP, Aspentech or OSISoft PI.
Corporate level Environmental Health and Safety or Data Historian systems can connect to CEMView using the CEMView OLE-DB provider to retrieve historical emissions data or the OPC interfaces for real-time data.
Alternatively, CEMCoRe can be used to consolidate the data from multiple CEMView sources and similarly, the CEMCoRe OLE-DB provider provides connectivity to the corporate level systems.
OSISoft’s PI System interfaces support direct connectivity to the CEMView and CEMCoRe systems by utilizing the OPC and OLE-DB interfaces for real time data and / or historical data.
The OPC Alarms and Event specification is the foundation on which the CEMView Alarm and Event handling mechanisms are based.
In CEMView, three distinct mechanism are supported.
Active Alarms and Events
Active Alarms and Events are generated by CEMView Server and all local and remote CEMView Client applications are automatically notified. Alarms and Events are classified and a rich, multi-level acknowledgement mechanism is supported. Features include automatic and user settable Reason and Action codes, ad-hoc memo logs and generic or user specific acknowledgement with passwords if required.
The CEMView Event Log window is available to browse historical alarms and events.
The CEMView Activity Log window is available to browse the system status and changes. There is an audit trail mechanism in CEMView that records all configuration changes made to the system.
The CEMView Activity log is an audit trail feature that is useful in ensuring that all changes to the CEMView system are recorded.