Programmable Automation Controllers (PACs)
A Programmable Automation Controller (PAC) is a rugged industrial embedded device with the software flexibility and programmability of a PC. Think of a PAC as a very, very smart PLC. It has the environmental specifications for operating temperature, vibration, and shock of a typical PLC. It runs a real-time Operating System just like a PLC. But unlike a PLC it supports an open flexible software architecture, and is programmable at a level that would typically be associated with a PC.
Use PACs for applications that are too computationally demanding for a PLC, in environments that are too harsh for a PC. Think PAC if your industrial application includes any combination of these requirements:
- Complex I/O, including verbose device communications, and mixes of high- and low-speed signals;
- Deep on-board memory for high capacity data logging;
- High-precision and/or traceable analog measurements;
- Custom algorithms for analysis and control;
- Remote data access or control, over Enterprise networks or the Internet.
The PAC as an Alternative to SCADA
The traditional industry solution to problems that require both industrially hard I/O, and PC level software smarts, is to implement a SCADA system - a small network containing one or more PLCs to perform the industrially hard I/O and local control tasks, and at least one PC to perform high-level software based tasks like data logging, supervisory control and HMI management.
This is not an ideal solution. Implementing and maintaining a SCADA system requires access to three distinctly different skill sets:
- Programming and deploying the PLCs - typically an electrical engineering function;
- Programming and maintaining the host PC - typically an IT department or PC specialist function; and
- Installing and maintaining the network - typically an IT department function.
It is rare to find a single individual with uniformly high skills in all these areas, which can severely complicate maintenance and fault finding.
A PAC combines the capabilities of both a PLC and a PC, so it can perform all the required functions of a SCADA system from a single device, without the separation of tasks over a network. One device, one skillset, and no network to maintain - the PAC wins by a knockout!
The Ultimate PAC
Many industrial automation companies now offer PAC solutions, but in our opinion not all offerings on the market meet the full definition of a PAC. In particular the requirement for open, fully flexible, industry-standard software support is often not fully realised.
In our experience the National Instruments LabVIEW Platform includes the ultimate PAC device currently available on the market. CompactRIO combines a real-time embedded controller, reconfigurable FPGA hardware, and ultra rugged modular I/O in a single LabVIEW programmable device. It supports analog acquisition up to 500 KSa/s, with control loop rates to 10s of kHz. It is fully network enabled, and can support multiple simultaneously active industry standard communication protcols.
To see details of relevant ICON Technologies projects that use PACs, go to the Projects Page, and select "Programmable Automation Controllers (PACs)" from the "Project Type" popup menu.