A new era in data recording

Developments in electronic data recording technology are opening up new possibilities for the collection, storage and retrieval of process data, making them appropriate for use in a host of new applications. John Jagger, product manager, recording and control products at ABB Australia, explains the benefits that electronic data recorders can bring and how they can be used to transform the way in which process data is collected and used.

Developments in electronic data recording technology are offering new opportunities for the way in which 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 use throughout the organisation.

One particular development is the addition of ethernet communications. Last year, automation industry experts, the ARC Advisory Group, predicted that shipments of device-level industrial ethernet products are set to grow 84 per cent annually for the next five years, despite difficult 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 ideal 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 communications, operators can now remotely access and download information from electronic data recorders, particularly ideal 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.

Greater accuracy and flexibility

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, which enable data to be downloaded into an 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 they occurred, unlike paper chart recorders which 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.

The ability to store and archive large quantities of data is another significant benefit of electronic data recorders, 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 additional equipment such as charts or pens, which can add significantly to the initial cost of a paper chart throughout its operational life.

Electronic recorders and 21 CFR Part 11

In the food and 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.

There is the potential with electronic records for tampering by anyone with the requisite skills. For this reason, in 1997, the US FDA introduced its 21 CFR Part 11 legislation, which sets out standards relating to data security and integrity that have to be met by electronic data recorders.

At the moment, the provisions of 21 CFR Part 11 apply specifically just to the pharmaceutical industry, although it is also starting to increasingly be adopted in the food industry as the need for traceability and validation of production procedures gain in importance.

The aim of 21 CFR Part 11 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 criterion focuses on three main areas, namely security, e-signatures and their validity and the management of the recorded data.

Security issues

To protect against the risk of tampering, electronic data recording equipment must be capable of ensuring total secur-ity by preventing unauthorised access and indicating any changes made that could affect the validity of the produc-tion process.

Products such as videographic data recorders, for example, allocate users with individual password and access rights, which allow them to be identified by the system and set restrictions on their ability to perform configuration changes which could affect the process.

Any alterations that are made are recorded by an internal audit trail, which logs the changes made and records who made the changes and when, as well as the details of all data files created and many other events key to process data security, such as calibration changes.

E-signatures

As verification that the correct proce-dures have been followed during pro-duction and to confirm any changes to configuration, 21 CFR Part 11 requires batch records to be electronically signed by a person with the relevant authority.

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.

Data management

Criteria for the way in which recorded data is managed and preserved is also set out by 21 CFR Part 11. Essentially, this criteria is 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 videographic recorders, specialised analysis software is available which enables all data recorded to be downloaded for easy viewing and analysis of recorded process data. The security of data files created by an SM recorder is ensured by the use of binary encryption, which preserves the integrity of the recorded data.

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 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 increasingly open up new applications for electronic data recorders.