Companies today face a growing number of challenges including reducing total cost of ownership (TCO) and improving efficiency. They must also deal with a growing amount of information needed to make informed decisions.
Conventional industrial recorders have been used primarily to monitor and record data in the field. In order to quickly extract information that is valuable to a user from this sea of data, recorders need to be made intelligent. This means they need to have advanced information processing and communication capabilities.
Whilst the market for paper recorders of all sizes continues to fall, the market for paperless or data acquisition terminals continues to rise at quite a substantial rate, new applications as well as paper recorder replacement programs are responsible as engineers start to appreciate the benefits of paperless networked solutions. Data acquired in production systems does not have to be isolated from the company’s decision making process any longer. The Networking capabilities of data acquisition terminals allows plant wide integration of data at any level within the company from the shop floor right through to the boardroom.
To understand what the new paperless systems can do it is important to understand how the network functions within them operate. A number of the new network features are outlined below with an example of possible use.
File Transfer Protocol (FTP) allows entire files of data to be sent across a network to a specified location on a server. To give a simple example of how FTP is used, imagine a plant with a number of data acquisition terminals (DAT’s) located in various key-monitoring areas. Each DAT would be plugged into the site network making it accessible from any PC connected to the network. Utilising commercially available FTP software each DAT could be configured to download a daily file via FTP to the server. The server could be set up such that it had a directory for each DAT, making it very simple to find the appropriate file for the right area for the desired day.
One important aspect of this example is the network loading. All through the day the DAT’s do not use the network and do not, therefore, add an additional load to the network, which could slow it down to an unacceptable extent. The only time the network is being loaded is when the files are transferred to the server from the DAT units, which only takes a few seconds for each unit. Re-viewing historical files is also very simplistic as the required file is simply opened from the appropriate drive on the network rather than transferring information physically from each device to be used on a local drive.
Utilising this functionality allows a large number of devices to be connected to the network without it becoming overloaded, or for the need to slow down the scanning rate of the DAT units. Various types of information can be transferred from the DAT units including data files, alarm files, and report files. For example, the weekly steam usage could be calculated for various areas of the plant and consolidated into a weekly and monthly report.
At any time several users from different locations can monitor the data acquisition terminals real time. This can be achieved through a number of different mechanisms such as OPC servers, proprietary software, or Standard web browsers. With proprietary software many other features of the DAT’s are available to the user such as configuration, but for simple and quick monitoring applications the web browser solution can be a real benefit.
A major plus for the web browser solution is that there are no license requirements, the only software needed is a web browser which usually comes as a feature of windows operating systems.
Other advancements in this field include fieldbus functionality, allowing analogue transmitters to be connected to a fieldbus system via the data acquisition terminal or direct connectivity of fieldbus inputs to a paperless system. This market is expanding at a remarkable rate and future advancements are already in the pipeline. The only thing we can do is to watch this space.