NI’s PACs replace PLCs for advanced centrifuge control

Austin, TX—Researchers at the University of Colorado at Boulder recently implemented National Instruments’ (NI) programmable automation controllers (PACs) and NI’s LabView graphical development environment to streamline experiments involving a 400 g-ton centrifuge.

By Control Engineering Staff May 31, 2005

Austin, TX— Researchers at the University of Colorado at Boulder recently implemented National Instruments ’ (NI) programmable automation controllers (PACs) and NI’s LabView graphical development environment to streamline experiments involving a 400 g-ton centrifuge. This device is one of the nation’s most powerful centrifuges, and is capable of spinning two tons of material at 200 times the force of gravity.

Using industrial PXI chassis and LabView real-time controllers, researchers replaced the existing 200 I/O-point PLC, along with 2,000 lines of antiquated PLC ladder logic, to create a more efficient, rugged and easily upgradeable system that reduces system setup time and increases reliability.

Users working with large centrifuges must handle a demanding environment, control large dc drives, and are required to perform control and data acquisition on several hundred I/O points. PXI’s ruggedness, modularity and reliability reportedly made it ideal for replacing the centrifuge’s existing PLC with an NI PXI-8176 embedded controller running LabView real-time software.

The university’s researchers bolted the new PXI system, which is more than 20 times smaller than the existing PLC system, into the same location as the original PLC. PXI offered I/O compatibility with the existing PLC system, helping researchers reuse original wiring and replace hundreds of individual conductors with standard Category 5 Ethernet. In addition, they replaced the existing collection of data acquisition equipment with a single PXI-based PAC running a Windows OS and LabView.

‘The rugged PXI form factor was ideal for withstanding stresses in industrial settings like the centrifuge, and its modularity and high level of integration increased the reliability and productivity of the system,’ says Robert Wallen, professional research assistant in UC Boulder’s civil, environmental and architectural engineering department. ‘We also saw substantial savings by using LabView to program both the control and data acquisition systems, and with LabView and PACs, we were able to reduce the system setup time by 75%.’

By using one development environment for the centrifuge control and data acquisition systems, researchers saved development time by reusing existing code and replacing ladder logic code with LabView code. The researchers used one development environment, LabView, and flexible hardware to create a solution for their control and data acquisition needs in a minimal amount of time with substantial cost savings compared to buying a new PLC control system.

NI adds that its PACs combine the flexibility of PCs with the ruggedness and reliability of PLCs. Its PAC platform consists of industrial hardware programmed with LabView from PXI for industrial control and data acquisition applications to Compact FieldPoint for distributed I/O and control, as well as CompactRIO for FPGA-based control. NI says its PACs are unique because they offer integration with motion and vision, and are based on commercial technologies.

‘The centrifuge control application at the University of Colorado at Boulder illustrates how flexible hardware and a single development environment can replace control systems traditionally implemented with PLCs,’ said Ray Almgren, NI’s product marketing and academic relations VP. ‘In addition, the use of NI PACs at this leading academic institution is an example of the NI’s commitment to supporting research and teaching with advanced technology as professors and researchers work to solve the challenges of tomorrow and train the engineers of the future.’

Control Engineering Daily News Desk
Jim Montague, news editor
jmontague@reedbusiness.com