Recent developments in electronic data recording technology are offering new opportunities for the way in which process data can be used.

As well as recording the details of a production process, electronic data recorders are opening up a wealth of new possibilities for the way in which data can be analysed, presented and utilised throughout the organisation.
One particular development is the addition of ethernet communications. In 2002, the ARC Advisory Group predicted that shipments of device-level industrial ethernet products were set to grow 84 per cent annually for the following five years despite difficult trading conditions in automation markets.
Ethernet's worldwide acceptance in industrial and office environments has created an eagerness to expand its responsibilities on the plant floor and beyond. Its performance capabilities make it highly suitable for tasks such as data monitoring and program maintenance.
Where data recorders are concerned, ethernet communications are helping to transform the way in which data is retrieved and accessed. Using ethernet, operators can now remotely access and download information from electronic data recorders, which is particularly beneficial for large sites using multiple recorders or for applications where data may need to be collected from several geographically remote sites - such as in the water and waste treatment sector (Fig. 1).

Variations in data

Electronic data recorders allow precise variations in process data to be recorded and displayed as required. They also offer a range of possibilities for presentation, including the ability to create and print graphs and reports.
Many suppliers can now also offer units that enable data to be downloaded into a Microsoft Excel spreadsheet, allowing it to be interrogated in greater detail.
The validity of the recorded data is also greatly improved by electronic data recording devices. Events can be automatically recorded together with the actual time when they occurred, unlike paper chart recorders that may rely on additional details being manually added to the chart by the operator. Most electronic data recorders also now enable authorised operators to add an 'electronic signature' to recorded data to help in tracing who was involved in the process and any changes they may have made that might affect product quality (Fig 2).
Another significant benefit of electronic data recorders is the ability to store and archive large quantities of data, particularly in industries where records are required to be retained for several years.
Electronic data recorders can also offer a significantly reduced cost of ownership. The solid-state construction of electronic data recorders means there are no mechanical components that need to be checked or maintained.
There is also no need to replace consumables such as charts or pens, which can add significantly to the initial cost of a paper chart recorder throughout its operational life.
In the food, beverage and pharmaceutical sectors, the main concern in the take up of electronic data recording technologies to date has been their ability to safeguard the security and integrity of recorded data.
Electronic records can potentially be tampered with by anyone with the requisite skills; for this reason, in 1997, the FDA (USA Food & Drug Administration) introduced its 21CFRPart11 legislation to set out standards relating to data security and integrity that have to be met by electronic data recorders (Fig. 3).
At the moment, the provisions of 21 CFR Part 11 apply specifically to the pharmaceutical industry alone, although it is increasingly starting to be adopted in the food industry as the need for traceability and validation of production procedures gain in importance.
The aim of 21CFRPart11 is to set out criteria by which electronic records and electronic signatures will be accepted in the place of paper records as proof of the validity of a manufacturing process.
In particular, this criteria focuses on three main areas: security, e-signatures and their validity, and the management of the recorded data.
To protect against the risk of tampering, electronic data recording equipment must be capable of ensuring total security by preventing unauthorised access and indicating any changes made that could affect the validity of the production process.

Videographic data recorders

In response to these needs, ABB has developed the Informit videographic range of data recorders. In these devices, all users are allocated individual password and access rights that allow them to be identified by the system and restrict their ability to perform configuration changes that could affect the process.
Any alterations that are made are recorded by an internal audit trail that logs the changes made and records who made the changes and when, as well as the details of all datafiles created and many other events key to process data security, such as calibration changes.
As verification that the correct procedures have been followed during production and to confirm any changes to configuration, 21CFRPart11 requires batch records to be electronically signed by a person with the relevant authority.
ABB's videographic recorders have a user-specific password-protected menu, from which the operator can elect to 'sign' for the data recorded by typing in a message. This 'signature' is then time stamped and logged by the recorder to provide a traceable trail of all changes made, including when they were made and who authorised them.
Criteria for the way in which recorded data is managed and preserved is also set out by 21CFRPart11. Essentially, these criteria are geared towards preserving the same standards of data integrity as during the recording process and to eliminate the risk of unauthorised tampering or alteration of recorded data.
In the case of ABB's videographic recorders, specialised analysis software is available that enables all data recorded to be downloaded for easy viewing and analysis.
The security of data files created by an ABB SM recorder is ensured by the use of binary encryption that preserves the integrity of the recorded data.

Information stored on all of the recorders in ABB's Informit SM range can be securely accessed via an ethernet network. An embedded web server provides online access to web pages created within the recorder containing details of real-time process data, which is archived in a secure binary encrypted format.
Continuing developments in recording technology, together with an increasing realisation of the benefits that electronic data recorders can offer - such as remote communications, immediate access to current data, enhanced security and improved reliability - will continue to open up new applications for electronic data recorders. m

Martin Binney is a product manager for ABB Limited. www.abb.com