Serving the needs of drive systems
Original article date: April 2000
A new drive server has been launched promising to save programming and commissioning time for drive systems. Tommy Miller reports
Imagine a situation where there is an inverter drive, a machine interface and a PC linked to the drive so that data can be collected for analysis in, say, Microsoft Excel. The PC can easily be used to write the PLC program for operating the drive, and for programming the machine interface to display the desired screens and to react to the user inputs.
Easy, so far. However, the machine interface and the drive both need to communicate with each other, which might not be so easy to achieve, especially if the two come from different manufacturers. Also, there is a need to define the data sets separately for the drive and the machine interface, and errors can occur here that may take some considerable time to find and resolve.
“There must be a better way,” came the cry from the engineers at Lenze (formerly known in the UK as Simplatroll). So now the company has launched the drive server and this new software tool should make life far easier. Similar in concept to a printer server, the Lenze drive server is an OPC-based interface that is installed on a Windows NT-based PC and instructed as to which fieldbus protocol to use. The drive server then recognises which drives are present and configures itself accordingly, building up a database of all the drive information. Parameter groups can then be arranged and named.
The main advantages of this alternative approach are that the data sets have to be declared once only, and that different fieldbus systems – perhaps serving different types of hardware – can access the database and communicate with each other, whether they are Can, Profibus, Devicenet or almost any other. Because the data sets are only declared once, there is a significant saving in programming time. Furthermore, the opportunity for making errors is vastly reduced, so the time taken up with debugging is also cut.
Lenze estimates that 30-40% of a typical drive project is spent on engineering the interfaces between the various items of hardware, and that a large portion of this time could be saved by using the drive server. After commissioning, further savings should also be possible due to simplified maintenance and upgrading.
- Lenze
April 2000