Tag Archives: programmable logic controller tutorial free

Productivity 1000 Series PLC System Hardware

The Productivity 1000 series of programmable logic controllers has a slim stackable super compact design. This is sometimes also referred to as a shoebox PLC because of the shape and way in which expansion modules are added. This new Productivity 1000 series PLC is the latest in the Productivity series of controllers that have hit the market.
Productivity 1000 Series PLC System Hardware
Productivity 1000 (Stackable Micro PLC)
Productivity 2000 (Micro Modular Programmable Controller)
Productivity 3000 (Modular Programmable Controller)

These three series currently make up the Productivity Series from Automation Direct.
Productivity 1000 Series PLC System Hardware

The Productivity 1000 series PLC provides the following features for your automation control panel.
– 50MB user memory – Can handle very complex applications easily.
– 4 built-in communication ports – Easy connectivity to your network. This would include your PC, HMI, Networks, etc.
– Data logging up to 32 GB on a microSD card
– Add up to 15 IO modules to communicate to your field sensors.
– Free Software and 30 days of free training with every CPU from Automation Direct.
– Interactive PLC Configuration Tool
– Tag Names
– Auto-discovery IO – Physical I/O tags will be generated based on each module’s position in the base. You can also reconfigure the setup and assign new tags manually.
– I/O Modules have QR codes under the wiring cover. This can be scanned so you can have the latest specifications/wiring diagrams for the module.
– Limitless PID – Autotuning – Individual or Cascade Mode – etc
– Web Server and Mobile Access
– Advanced Software instruction set

We will be looking at a lot of these features of this powerful controller. Let’s start by looking at the hardware. Continue Reading!

Omron CP1H Data Control Instructions

The data control instructions in the Omron CP1H programmable logic controller are used to manipulate the outputs based upon control conditions. Control is the main purpose of these instructions within the PLC. Instructions include PID (Proportional, Integral, and Derivative), PID with Autotuning, Dead Band Control, Limit, Dead Zone Control, Time Proportional Output, Scaling, etc.
We will be looking at some of these instructions in the Omron CP1H PLC. Examples of the instructions will be presented. Continue Reading!

Omron CP1H Program Control Instructions

The Omron CP1H programmable logic controller has several different ways to control the program and the way in which your program executes. Sequence control, Subroutines, and Step instructions can be used. These are just a few ways in which the controller will execute your logic using a synchronous PLC scan. Understanding the PLC program scan will explain the synchronous and asynchronous program scanning.
Interlocks, Jumps, For Next Loops, Subroutines and Step instructions are some of the ways in which we can control our program in the PLC. We will be looking at some of these instructions in the Omron CP1H PLC. Examples of some of the instructions will be presented. Continue Reading!

Omron CP1H PLC Programming Counters

The Omron CP1H series of programmable logic controllers are capable of having 4096 basic counters. There are two basic counter instructions in the PLC. Each of the basic instructions can be either binary or BCD. The memory area for counters has separate areas for the Counter PVs (Present values) and the Counter Completion Flags. We will be looking at the basic Counter instructions in the CP1H along with some programming examples. Continue Reading!

Omron CP1H PLC System Hardware – CP1 Series

We will now look at the system hardware of the Omron CP1H controller. The Omron CP1 series of programmable logic controllers consists of three different units. CP1E is the cost-effective unit, CP1L is the high-performing controller that can come with embedded Ethernet and the Omron CP1H is the position control and comprehensive programmable logic controller.
We will be looking a the Omron CP1H for this series, but a majority of the information can be applied to the CP1E and the CP1L controllers as well.
Let’s start by looking at the Omron CP1H hardware.

The CP1 series is designed with the same basic architecture as the CS and CJ Series. The special I/O units and CPU bus units of the CJ series can then be used. Always use CPM1A expansion units and CPM1A expansion I/O units when expanding the I/O capacity. The following diagram indicates the position of the unit with respect to the CJ and CS series hardware. Continue Reading!

How to Troubleshoot a PLC – Ladder Logic

We will look at how to troubleshoot a plc racing condition.
Two examples are explained in racing conditions in the PLC. The PLC will update only at the end of the program logic. Items set will not happen until the I/O is refreshed. How to trigger events when you want them is discussed.
Your control system does not work. Where do you start? Let’s walk through a series of questions to determine where the problem lies.

how to troubleshoot a plc



Troubleshooting a PLC – Starting

Is this a new installation or a previous installation that was running fine? Determine if the system has been running well in the past and has currently stopped working correctly. This is the indication that the problem relies upon the system.

Is there anything that has happened outside of the system? Has there been a lightening strike, blown drives on other systems, etc.?  This can point to the original cause of the malfunction.

how to troubleshoot a plc

Gather Information for Troubleshooting

What is the system doing now, and what should it be doing? Gather all of the information you can from every resource you can.

  • Supervisors  – machine, location, time of the error, other happenings in the plant, etc
  • Operators – What is it currently doing? What should it be doing? What do you think is wrong?
Operators of the equipment are your key resource in finding, correcting and ensuring the error does not happen again. They know the equipment from an operational point of view which can assist you greatly in troubleshooting.
PLC fatal and non-fatal errors:
Troubleshoot a PLC

If the machine is still running partially, then this is an indication of a non-fatal error. Cannot run at all is usually a fatal error.

how to troubleshoot a plc

Take a look at the PLC indicator lights on the CPU. Refer to the operation manual for the PLC for troubleshooting specific lights on the CPU. The following are general tips:

If no lights are on, the possible cause is a power supply. This is usually the most common of errors on a PLC system. Meantime before failure (MTBF) is rated on the lowest rating of components which is typically the power supply.

If the run light is on and an error light is flashing, this usually indicates internal errors such as batteries, scan time, etc. It is usually not the reason for the lack of operation.

If the run light is on and no other errors are seen on the CPU, we can put the PLC program at the bottom of the list of items that could be the cause.

Check the input cards of the PLC. You should see the individual sensors lighting up the inputs. If not, check the power supply to the input card/cards.

Ask the operator what is happening and what is supposed to happen. Try to follow the sequence of events in the PLC to determine whether an input or output device is not working.
Some items to watch:

New PLC installation troubleshooting

If this is a new PLC program that you are doing, start with a logic flow diagram. This will determine the procedure to start programming.
Every program can be done in several ways. The best method is the most documented one.

Documentation is the mark of a good program.

how to troubleshoot a plc

Some trouble with new programs can be racing conditions. This is usually a case of not understanding how the PLC scans logic. The PLC will generally scan from left to right, top to bottom. The output bits/words are available to the inputs of the next rung of logic. (Modicon PLCs will scan differently.) Actual outputs and information are not read until the end of the scan of the PLC. Racing conditions happen when the outcome is set on multiple rungs but will not get set until the end of the scan. Think of it as the last action that will always win, so if this happens, move the logic to the end of the program and see if it works. Then go back and see where the output was also set. (Refer to your programming software on how to get cross-references.) Cross-reference guides are ideal for this purpose.

how to troubleshoot a plc

We have discussed just a few troubleshooting techniques. Hopefully, now you know how to start looking for the errors in your system. Let me know how you make out.

Watch on YouTube: How to Troubleshoot a PLC

Do you know of additional tips or methods to share?

If you have any questions or need further information, please contact me.
Thank you,
Garry



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