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Hello everyone, Not sure if I have the right forum, so please forgive me; but... I have a control loop to tune, and it's the first one that I've ever been in charge of. My question is about tuning PID. The loop I have to tune is controlling a pressure reactor to setpoints ~3000psi with a safety valve that blows around 4500 psi. My question is what procedure you might go through to tune it safely. I'm quite honestly a bit afraid of the high pressures and I really don't want to make anything "pop". What also makes it tricky is that the reactor has to heat up to get to full pressure. Without heat, the reactor will reach ~1000 psi, then it sits there for a long time and eventually the heat kicks in and the pressure can rises up very quickly. I currently have a very small gain value, something like 0.009 and an integral time of ~7sec. I'm getting pretty good results in that the PID controller will bring the reactor up to pressure without major overshoot, but it oscillates at ~ +-100psi, which seems excessive to me. [The situation is further complicated by the material in the reactor, a slurry, which has variable density often causing pressure spikes and drops as thicker sediments blob through. Then, valves that we are using to control appear to be only opening ~10% to maintain setpoint, meaning I only get 1/10th the resolution I would be hoping for. Also, the valve responds quite slowly to command signal changes. The controller will be attempting to open the valve in 0.1% increments, but it only responds at minimum to 0.4% changes in the control signal, and when it reverses directions it seems to only respond after a ~5% change in control signal. This alone appears to cause oscillations that I don't know if a PID loop could ever get ahold of.] Anyways, aside from the obvious valve issues, is there any tips for tuning a system with this high pressure? I need fast response, but slow buildup... (Oh yeah, I'm also having to use connected components workbench for control software. At least the newest version of CCW seems to have a nice iPID control block; but man, I have never had to ctrl-alt-delete a program more times due to freezing while building or downloading...so frustrating...).

I want to maintain my CCW PLC design in Source Control (Bitbucket) but I want to only check in the files that are needed for the build (the source) and not the build products. Does anyone know what files are the "source" files for a design?

Hello, We replaced a motor so I decided to do the static auto tune by using CCW. When I clicked "Finish" button at the end, I got a message "Failed to write a new value message - This parameter is only editable on the Identity Page." Is it because I opened a project with using discovery option? Has anyone seen this error before? Any help would be appreciated. Thank you Sinamics(G120) - F7800.pdf

First of all, I'm running version 20.01.00 CCW. I have a project that uses a mciro870 and panelview 800. It also has 11 powerflex 525 VFD's attached, all ethernet. Everything has been going well but today I hit a wall when importing tags into the Panelview device group. I currently have a little over 800 tags and will have about 1400 I think when finished. The Plc section shows tons of memory available and when I check through 'config' on the Pv800 itself, it also has tons of memory left. When I do the import, it brings in 744 tags and then skips the remaining one. It even includes that in the msg block after the import. It has to see that tags or it wouldn't know that they are being skipped. I've been trying to work with Rockwell support ( of course I got the new guy who's never seen the software before) and my local distributor. I've looked through the rockwell knowledge base, the manuals and online and I haven't seen this problem posted. Does anyone know if there is a limitation on the number of tags? I can't image an odd number like 744. thanks, mark

Hello, I have a Micro850 PLC that has 5 2080-IF4 plug-in modules attached. Each of these modules are programmed to read 4-20 mA output signals from various sensors. It also has interlock switches connected to embedded digital input ports. When I download the program to the PLC from CCW, the message prompt that enables 'Remote Run' does not appear. I can't seem to switch the controller to run mode. Moreover, while connected, the I/O tags all read 0. I have tested the sensor wire leads with multimeter and they do give out output signals in the range of 4-20mA. Not sure why CCW is unable to read. The DI status LEDs also light up when I turn on the switches. I assumed that it might have to do something with the firmware, so I reset the firmware to default, that didn't help either. Any ideas on what the issue is or how to fix the issue? Thanks.

Hello all, I am working on a project where I am communicating with a Mensor CPT6100 pressure transducer using a Micro-850 PLC. For this, I have used an AWA instruction to write some ASCII characters to the sensor. The sensor then responds to the write instruction by sending ASCII characters to the RX buffer and I used ACB and ARD instructions to read the ASCII characters. Now, I have set the ACB trigger type to 0 (msg triggered only once) and it successfully reads from the sensor. However, when I set the ACB trigger type to 1 (msg triggered multiple times), I do not get any reading in the ARD block. As a matter of fact, the ACB Q bit switches off every time the program is executed when the trigger type is set to 1. I am trying to get continuous readings from the sensor, but when the trigger type is set to 0, the program latches on to the first and only reading and it won't change. My question is, how can I change my program so that it can continuously and autonomously read from the sensor without me having to manually trigger the AWA and ACB instructions every time. I am attaching the program to this thread for your reference. ASCII_Test_Copy.ccwarc

I have been working on a PLC project that requires sending ASCII commands/queries to an external pressure transducer using the Micro 850 PLC (2080-SERIALISOL module) via serial port communication (ASCII protocol) and in response the PLC would read pressure readings from the transducer. I was able to write a ladder logic program that reads ASCII code from the transducer and converts it into string and inversely converts string output from the computer to ASCII and sends it to the transducer. However, I am uncertain as to how I should send the command string from my computer so that the external transducer receives it, recognizes it after the <cr><lf> is encountered and sends a pressure reading. Any suggestions as to how I can type in commands from my computer and receive responses from the transducer?

I have a function that reads ASCII code from a transducer, converts the code into characters and places the characters from the serial buffer into a string. Now, I am trying to convert the value in the string into a 64-bit float number. Any ideas on how to do that on the CCW?

Hi all, I am new to the forum as well as being new to programming PLC's. I am trying to set up a simple data logging program using a Micro830, taking pulse readings from an energy meter. I have completed the program using tutorials, but i am struggling to set up the data log. The DLG function shows error 8 (real time clock is invalid) so i have tried to set up a real time clock but there are very little tutorials on how to do it. The RTC currently shows status 2 (RTC set operation failed). Please could someone please help me out so my boss doesn't disown me :( Thanks so much in advance! Andy

Hello all! I have a two part question - both revolve around using Rockwell's CCW software. 1) in rs500 you can mov a value into the an int memory slot and call that int up later on for comp. instructions to see where you're at. Example, if x switch is active, mov value 0 into N7/0. If y switch is active, move value 1 into N7/0. If both x & y are active, move a value of 2 into N7/0. How is this done in CCW??? I've found the mov command but not sure where/how to store this value. 2) How do does one shot [ONS] work in CCW?!? From what I've gathered the r_trig and f_trig is its replacement, and thought it made plenty of sense. But no matter what I do the triggers never work out correctly. Thanks, -g

Hello - I am currently setting up a program to control a downlane conveyor motor and ran into the issue of operators leaving the conveyor on through their breaks/at the end of the shift.... I know, shocking . Anyways, the essentials of the program are the following - ladder logic, start/stop PB station, a sensor that says when I've seen a box for x-amount of time I will turn off, when the eye is clear for x-amount of time I will turn back on. When trying to 'solve the problem' of the operators leaving them on, I figured this would give me a chance to use a RTC (real time counter) and program it so that at various times of the day I will send a single shot to verify the relay is CT is open. I've enabled the RTC on the Micro810, dropped a TOW but do not really understand how to set the TOW block up. Hopefully that all makes sense. Thanks, grubb

Hello , I'm using Allen Bradley Micro850 - 2080-LC50-24QWB PLC. I downloaded a program to that PLC by CCW. My customer wants to build an application (like a GUI) on a PC which ables to read and write the I/O's , therefore he needs me to send him the registers of the I/O's that i have used in the program. so i woule like to know the register for every tag or I/O. where can i get that information from? for example , i would like to read : _IO_EM_DI_00 , how could i know what this tag's modbus register is? thanks in advance.

Hello, I'm using Allen Bradley Micro850 , 2080-LC50-24QWB. I wrote a program using Connected Component Workbench which reads certain indications and controlling contactors. My customer would like to connect that PLC to a PC by an Ethernet cable RJ45 and read those input registers and write those output registers into his application that he had built. He would like to know the commands in order to read or write the data and the TCP/IP data structures and frames. I would like to have the registers mapping of this PLC as well. i have been searching this information in the data sheets and have found none. i hope you could help me or at least instruct me becasue that's really urgent. thanks in advance.

Hi everybody, Recently, I started working on a project. I want to develop a program for a Micro820 controller (2080-LC20-20AWB) using CCW (Connected Components Workbench). I built a little motor circuit for testing purpose. However, after building the program and downloading it to the controller, I tried to connect to my controller via CCW, but I can't. When I click the button "Connect", CWW crashes OR a window saying : "The controller has unnacepted changes" appears and asks me if I want to "Download current project to the controller" (wich I already did) or "Upload the project in the controller to overwrite current project content" (wich is grayed out). When I choose to "Download current project to the controller", CCW starts downloading the resource, but fails. In the "Output" window, there's a line saying : "Download failed for Device:Micro820: An error occured while reading from GETACTIVERESOURCELIST.". The problem is that there's no documentation at all concerning this error. I even tried to reinstall CCW, but it didn't fix the problem. I joined some images so you guys can see what I'm talking about. Don't mind asking for more details !

Hi, My Powerflex 525 Drive is currently working in the Project. I wanted to observe the drive parameters when the drive is running and live with PLC. I usually do that by getting online with the PLC (1756L72S) from RSLogix5000 and then by going in to the Drive Properties from the I/O Configuration folder i use to click on Drive tab and from there i was able to observe all the Drive parameters with the real-time values on which drive is running. Now when i try to observe the Same real time parameters on my other PF525 drive, i follow the same procedure as mentioned above till going into the Drive properties and when i try to click on drive tab its gives me a Screen with a message "AUTOMATIC CONNECTION FAILED". The status of drive in the drive properties still shows me that the drive is running. How can i observe the Real-time Parameters for this other PF525 Drive? Thanks.

Hiya Guys, New here (first post!) - and I'm fairly new to Connected Components Workbench, so apologies for the mammoth post! I am currently developing a System using one Micro850 PLC and one PanelView C600 HMI. I am able to update the current HMI time by sending Unsigned-Integers to Global Connection Tags: System Clock – Hour ($SysClockHour);System Clock – Minute ($SysClockMinute);System Clock – Second ($SysClockSecond);However, if using the same “update time” more than once, this method does not work as the HMI is looking for a “change” in a Tag before an update occurs (Tag-specific). For example, we require to be able to receive a “synchronisation signal” on a digital-input on the PLC each day at 15:00:00. This will only work once as, even though the HMI’s current time updates every second, I will still be sending the values “15”, “0”, and “0” to the above Tags (which will therefore not force an update – as they haven’t changed). I cannot reset these Tags without updating the current Time – as any number “out of range” causes an error (incidentally the errors are shown on the HMI to occur on Tags “SysClockSecondTimed”, “SysClockMinuteTimed”, and “SysClockHour” – note the omission of the word “Timed” on the Hours error…). There appears to be no reference to these “Timed” Tags anywhere in CCW, and I have no idea why the “Hour” update errors on a different (the correct?!) Tag. It’s a pretty confusing problem and difficult to explain… it took me a while to get my head around it – and I can see what the code is doing! J I've looked for documentation on how these Global Connection Tags work, but I can't find anything. Everything I (think I) know so far is from extensive testing... so if anyone knows of any documentation, or has any suggestions as to how I can achieve the required result - that would be massively helpful! Thanks for taking the time to read all this! Cheers, Steve.