Building Better, Tougher, and Simpler Industrial Systems
The standard tools of choice for implementing a local monitoring & control or test system in industry have traditionally been the PLC or the PC. The PLC is very robust and reliable, but lacks the processing power, data management flexibility, and network functionality that is required for demanding industrial applications. The PC is powerful, flexible and network aware, but is not industrially robust.
So how do you deal with applications that demand both PLC robustness and PC power? ICON Technologies uses PAC technology integral to the NI LabVIEW Platform to build industrial systems that push or exceed the boundaries that can be achieved using traditional PLC/PC-based devices and SCADA networks. To understand more about how the tools in the NI LabVIEW Platform compare with traditional PLCs see our Frequently Asked Questions (FAQ) page for the NI LabVIEW Platform in industrial environments.
What is a Programmable Automation Controller (PAC) and Where Would You Use One?
A 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 robust, 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;
- Integrated machine vision and/or multi-axis motion control;
- Deep on-board memory for high capacity data logging;
- High-precision and/or traceable analog measurements;
- Custom algorithms for local data analysis and control;
- Remote data access or control, over Enterprise networks or the Internet.
- Full network awareness, including the management of multiple simultaneous communications protocols, and data distribution & remote access over Enterprise networks and the Internet; and
- The flexibility to quickly adapt the system to suit changing needs and new technologies as they arise.
These requirements are typically found in, but not limited to:
- Pilot plants or pilot scale facilities
- Control systems for small-to-medium scale plants that produce boutique or specialised products; and
- Specialised control and automation sub-systems that exist within larger, more traditional DCS environments
Bringing the Industrial IoT to a System Near You
A lot has been written and spoken about the industrial Internet of Things (IoT), sometimes also talked about as Industry 4.0. Whether you believe that the IoT is already here, or you think that it has a long way to go, there is no doubt that some aspects of it are here, and here to stay. In particular, many manufacturers of complex industrial machines and systems are building significant local processing power, diagnostics and internet connectivity into their devices. These so-called “edge devices” – able to collect data and make intelligent decisions at the coalface, and communicate the results directly back into the organisation’s business systems – are the key to the industrial IoT.
But what about all those “un-intelligent” machines and devices already in the field? Do they have to exist outside the industrial IoT? A PAC Controller is rugged enough to be deployed at the coalface, but includes all the processing power and network communications capability necessary to act as an “edge device”. By designing new measurement and automation systems around PACs, and upgrading legacy systems to include PAC Controllers, all your systems will be IoT-ready.
The PAC as a Smarter 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. Each component of the system must be functional for the overall system to work as intended. A simple network failure that limits data transfer and communications between the PC and PLC nodes can invalidate the whole system. And managing the skills base, spare parts and maintenance schedules to support such a heterogeneous system can be complicated.
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. So it is a more robust and capable solution for many applications that would traditionally be handled by a SCADA system. One device, one skillset, one spares inventory, and no network to maintain – the PAC wins by a knockout!
Traditional PLC-based SCADA systems will continue to be widely deployed in many sectors of the measurement and automation market. But substituting a more robust PAC Controller for the fragile PC in the supervisory role makes a lot of sense. ICON Technologies can upgrade or extend the functionality of legacy SCADA systems with modern PAC components.
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 protocols.