A PLC simulator (also known as a programmable logic controller (PLC) simulator) converts your existing PC into a virtual PLC. With many different PLC manufacturers in the marketplace, choosing a PLC to teach programming techniques can be a difficult decision. Even if you choose a particular brand, the cost of equipping your laboratory with that PLC and its associated programming software is very often above the available budget. A software-based simulator is a good solution as it cuts the cost of setting-up multiple stations in your lab. A PLC simulator like LADSIM would fulfil the above ideal stipulations.
The PLC Simulator
LADSIM is a fully-functional Ladder Logic Editor and PLC Simulator that incorporates all the basic functions used in plc programming. The desktop simulator has
- Shift Registers
These enables you to develop ladder programs efficiently. The aim of a simulation is to recreate ‘real’ process in order to give practitioners the chance to test the understanding of something like Ladder Logic Programming. For each simulation you must develop the necessary ladder code to effect safe control of the scenario. A programmed simulation like that can be used as a stand-alone teaching aid, as well as being capable of controlling external applications via one of your PC Internal Interface cards.
Examples Of A PLC Simulator
- The SIMATIC S7-200 Micro PLC
- The PSIM PLC simulator
The SIMATIC S7-200 Micro PLC – also called a mini PLC), which is fast, communication-capable and highly productive in real-time mode. The consistently modular design facilitates the creation of tailor-made, expandable solutions in the low-end performance range. The S7-200 Micro PLC can be used as either a stand-alone Micro PLC solution or in conjunction with other controllers.
The PSIM PLC Simulator – The PSIM is in essence three programs combined into a single package. First, PSIM contains a PLC Ladder Logic editor that allows users to create and edit PLC programs using Allen Bradley PLC-2 family instructions. Secondly, PSIM emulates the scanning sequence of a PLC. When placed into the “RUN” mode, the users program is scanned and the appropriate I/O is updated just as would occur in an actual PLC. Thirdly, PSIM contains a number of animated simulations which respond accurately to the inputs, and outputs of the emulated PLC. A conveyor based filling line, Traffic intersection and Batch mixing simulations present life-like challenges for the student programmer.
More About The PSIM PLC Simulator
The obvious bonus of the PSIM PLC simulator is that it is free. PSIM was developed in 1993 when training for Allen Bradley PLC2 and PLC3 processors was at its peak. At the same time computers were showing up everywhere in Educational and Training facilities. What was needed, was a software based PLC training package that would run on these new computers and reduce if not eliminate the need for $25K-$50K PLC training stations. Also, if the software could also simulate some real-time industrial processes, so much the better. PSIM was developed to fill that niche. Even though PSIM is DOS based and emulates an older generation of PLCs, it is still a valuable tool for introducing students to the fundamentals of PLC programming.
PLC programming is the individual programming of a programmable logic controller (PLC) or programmable controller.
- A PLC is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or lighting fixtures.
- Programmable Logic Controllers and Motion Controller – Machine Design offers engineers useful information regarding programmable logic controllers, articles and diagram information.
- The PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact.
- A PLC is an example of a real time system and is individually programmable – which is what is defined as PLC programming.
Back in the day – the day being the early 80s – the programmable logic controller unit was programmed using proprietary programming panels or special-purpose programming terminals, which often had dedicated function keys representing the various logical elements of PLC programs. These programs were then stored on a track cassette tapes. Facilities for printing and documentation were very minimal due to lack of memory capacity. The very oldest PLCs used non-volatile magnetic core memory.
These days technology has progressed so fast that programming PLCs is an entirely different ball game. It’s become far simpler and it’s more a kind of PLC programming for dummies now. PLCs are now, more often than not, programmed using application software (PLC Software) that has been specifically written for use on desktop computers, and connecting between the desktop computer and the PLC such as via Ethernet or RS-232 cabling. This kind of software allows for easy editing and changes of the ladder style logic as well as sometimes offering additional functionality to assist debugging and troubleshooting the software. Some of these programs even come with a PLC tutorial on programming, which covers most PLC basics. Finally, the software may allow uploading and downloading of the program between the computer and the PLC, for backup and restoration purposes.
- PLC programs are typically written individually in a special application on a personal computer, and then downloaded by a direct-connection cable or over a network to the PLC.
- The program is stored on the PLC, either in battery-backed-up RAM or some other non-volatile storage device or flash memory.
- Often, a single PLC can be programmed to replace thousands of relays.
- That very concept shows how the advent of the PLC has moved along with the technological times and has therefore made life easier for all involved, saving industrial operations time and money.
An example of a PLC programming tool for PLCs is Omron PLC software’s User Manual for CX-Programmer. It is a PLC programming tool for the creation, testing and maintenance of programs associated with Omron Sysmac, CS/CJ-series , CV-series and C-series PLCs. It provides facilities for the support of PLC device and address information and for communications with OMRON PLCs and their supported network types. The CX-Programmer operates on compatible PC with Pentium-II or better central processors, including Pentium II. It runs in a Microsoft Windows environment (Microsoft Windows 95, 98, Millennium, 2000 or XP and NT4.0 with Service Pack 5 or later).