What are the 3 processor modes?

Can someone explain the 3 modes that are physically located on the CPU? What are the modes and what makes them different? What can you do / not do in these modes? Are these the same modes that are on the RSlogix software in the top left corner? Thanks

Look at a manual.
Seriously. Expend at least that tiny bit of effort.

It really does sound as if you're trying to get someone to do class assignments for you.

If you can't be bothered to do these things for yourself, then you might as well just quit today and find a different career to pursue. An ability to do research and find your own answers to questions is absolutely critical if you actually want to purse this line of work.

I think this is more of a case of "thrown into the deep end" rather than "do my homework".

A-B controllers traditionally use a physical keyswitch to command RUN and PROGRAM modes.

RUN is what you think it is; the controller is executing its control program on a continuous loop.

PROGRAM can be thought of as "Idle" or "Download" or "non-executing Edit" mode. The controller has a user program, and can respond to messages on its communication ports, and even read Input data. But it's not running the user program and does not set any output instructions or values or physical module channels.

The REMOTE position of the keyswitch means that a session of RSLogix software can change the controller into either RUN or PROG modes, and that edits can be performed while in RUN mode.

If the keyswitch is all the way in RUN mode, also called "Hard RUN", software cannot change the operation mode of the controller. Similarly, if the keyswitch is all the way in PROG mode, software cannot change the operation mode of the controller.

Most controllers spend their days and nights in Remote RUN mode, so that they can be easily accessed over the network and edited, while doing their control job.

Lots of folks forget that you can prevent anyone from editing or messing with your controller just by switching the key over to RUN mode.

Thanks Ken! This is close to what I have in my notes. I needed verification. Lets say the physical key switch is in the REMOTE position. I fire up my software and want to make an edit in the program while its executing. Is this mode now referred to as REMOTE PROGRAM? So now I'm done with my edits and finalize them. I will break this part down to two questions. Will it convert to REMOTE RUN automatically or do you have to select the function after your edits? Is this the name of the position, REMOTE RUN mode?

In conclusion, are REMOTE RUN and REMOTE PROGRAM software elements of the physical REMOTE mode?

To The Top!

In general, the machine does not have to switch from Remote RUN to Remote PROGRAM to perform an edit.

In fact, that's one of the things that distinguishes controllers with "real" online editing from those that quickly switch out of RUN mode and back when you perform an edit. Notably, the Koyo/Automation Direct controllers do this, and while it works fine for many processes, some machinery and processes cannot tolerate a pause in the control loop.

Generally a ControlLogix will be running along in Remote RUN mode.

You'll connect up to it and start an edit. Only the specific rungs (or function blocks, or ST routines) you are working on will be affected. You'll go through the Accept and Test and Finalize steps. The controller never leaves Remote RUN mode or stops executing the program.

The usual reason for switching to Remote PROGRAM mode in a ControlLogix is to prepare for a program download or to perform a nonvolatile memory store or restore function.

Logix Controllers - Key Switch Modes

To add to Ken's info...

StoneNewB said:

...Lets say the physical key switch is in the REMOTE position. I fire up my software and want to make an edit in the program while its executing. Is this mode now referred to as REMOTE PROGRAM?...

Click to expand...

No.

If the key is in the REM position and the program is running, and you open the software and go online, you will see the key position displayed in the software as "REM". You will also see the status "Rem Run", and to the right, the small controller icon with a dropdown arrow will be Green. To the right again, the status box will be Green and the text "Run Mode" is displayed beside it. The controller is still in REMOTE RUN mode. If you now make and apply edits, the controller remains in REMOTE RUN mode throughout. Here, the controller never goes out of REMOTE RUN mode, and never enters PROGRAM mode. This is Online Editing while in REMOTE RUN mode.

To change the controller to REMOTE PROGRAM mode, you would have to select the Green dropdown arrow icon and select Program Mode. This will take the controller out of REMOTE RUN mode and into REMOTE PROGRAM mode, stopping the execution of the scan. Now you will see "Rem Prog" and to the right, the small controller icon with a dropdown arrow will be Blue (Turquoise). To the right again, the status box will be now be Gray and the text "Program Mode" is displayed beside it. If you then make and apply edits, this is similarly applying Online Edits, but now it's Online Editing while in REMOTE PROGRAM Mode. Once finished editing, you select the dropdown arrow icon again and select "Run Mode". This takes the controller out of REMOTE PROGRAM mode and into REMOTE RUN mode, re-enabling the execution of the scan.

StoneNewB said:

...are REMOTE RUN and REMOTE PROGRAM software elements of the physical REMOTE mode?

Click to expand...

Yes.

Physically, there are three positions of the key switch, but there are actually five selectable modes available for the Logix controllers. Three of those are accessed while the key is in the REM position.

Key to the left: RUN mode (1)
Key to the right: PROGRAM mode (2)
Key to the centre: REMOTE mode (3, 4, 5)

In REMOTE mode you can select through software...

REMOTE RUN mode (Rem Run)
REMOTE PROGRAM mode (Rem Prog)
REMOTE TEST mode (Rem Test)

REMOTE TEST mode is also accessed through the dropdown arrow icon. Alternatively, all the modes are also accessible through the "Communications" dropdown menu at the top. Now you will see "Rem Test" and to the right, the small controller icon with a dropdown arrow will be Yellow. To the right again, the status box will be now be Gray and the text "Test Mode" is displayed beside it. REMOTE Test mode allows you to execute the logic as if in RUN mode, except it will not manipulate the Outputs. The Outputs are set to the same state as when in PROGRAM mode.

As mentioned, when in "Hard Run" mode i.e. key to RUN, you can "Start Pending Rung Edits", which will only apply the edits in the software offline, and not in the controller that you are online with i.e. you cannot Accept, Test, Assemble, or Finalize rung or program edits to the controller. Pending Rung Edits, that only exist offline, even though you are online, will have lowercase letters "i,r,d". If you start a Pending Rung Edit and then go offline, you will see it is still pending. With it still pending, or cancelled, you can go back online. this is because the offline project and the online project are still matched. If you go offline with a pending edit and accept it, and then try to go back online, there will be a mismatch, because the two are now different. You will get a message: "The open project has offline changes that are not in the controller." Upload/Download, etc.

Between selectable and non-selectable, the Logix controllers can be in any one of seven modes, that I know of. The last two being LOAD mode and FAULT mode.

Regards,
George

Crystal clear now

Thank you so much!

There is, or at least there was a "TEST" mode too. It ran the program, but all the outputs were disabled.

Zombie thread alert!

Lets take this to another prospective, If you are talking about RW then yes Ken is right, however, in general there are many different types of controllers. For examples: RW do have run/remote run & stop. Siemens traditionally on older models only have run or stop (not forgetting the reset position (many have found that one & cleared everything) In this processor in run mode you can download the total program, although it will download in correct order if you neglect to add certain blocks (not in the source file it will go into stop), Mitsubishi will allow a limited change to be downloaded in run mode and does not have a remote run mode, this is limited to a rather small change. some smaller models will not allow on-line change in run mode at all and will request a remote change to stop. The only thing I will add that it is imperative that a programmer is aware of on-line changes and it's consequences.

I don't see a test mode in studio 5k, but that seems very useful. Would program mode do the same?

There is a "TEST" mode in Studio 5000. It's not selected by the keyswitch. It is selected via a dropdown menu in the controller status.