swimmy67

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Posts posted by swimmy67

  1. Posted

    Hello all, My employer wishes for me to evaluate the Siemens S7-200 micro PLC. In our facility we currently use Mitsubishi FX PLC's. We have had a few customer requests for Allen Bradley PLC's. We are trying to find a solution that we will use for the next five years. This will be a move exclusivly to the product lines. What are the pros of the S7-200 system? What are the cons of the S7-200 system? I look forward to the responces. Thank you, swimmy67

  2. Posted

    One other thing you may want to concider is the speed of the com port. From the Transfer Set-up you can choose the speed. The FX2N will not communicate if the speed is faster than 9.6K. When connecting to a new FX2N you may have to set this and save the program to save the communication settings. Set the comm port to your Comm port ie.. Com 1, Com 2 etc. Set the port speed to 9.6K. and then click test communications. I hope this helps. swimmy67

  3. Posted

    Colin, During my years programing the SLC 500 or even the MicroLogix PLC, I have got into the habit of uploading and saving the existing program residing in the PLC before I do any edits. I too have found out the hard way that the data could be different from a backup file that was used for the first download. I have applied this practice on all of the PLC's that I work on. If I go to a customers location to edit the program, I first upload and save the existing program even though I have the original copy of the program. I want the latest and greatest program to fall back on. I hope this helps. swimmy67

  5. Posted · Edited by swimmy67

    Ryan, What this means is that you need to reset the fault in the processor. The cause of the problem was removing the power supply under power. This is what caused the fault light to start flashing on the processor. You will need RSLogix 500 and RSLinx to communicate with the SLC to clear the fault and a copy of the program to download back into the SLC. I hope this helps. swimmy67

  6. Posted · Edited by Michael Walsh
    Repaired Links

    Hello all, Here is the attached ladder file for the FX3U PLC. I saved the Ladder file in PDF format so everyone will be able to see. Thanks, swimmy67 Edit: I have attached both files for review. FX3U PLC LADDER 1.PDF Original ladder diagram for unsuccessful PID auto tuning. FX3U PLC LADDER.PDF Edited ladder diagram where the PID auto tune was successful. FX3U_PLC_PROGRAM_LADDER.pdf FX3U_PLC_PROGRAM_LADDER_1.pdf

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  7. Posted

    Hello All, After running trials and changing code I was successful with the Auto Tune today. The whole issue was running two different PID loops. One for Auto Tune and one for running the process control. I changed the code to run only one PID loop. With the auto tune I set the parameters and loaded them into the pid parameters. After the auto tune finishes, the bits that were set for auto tune turn off. I monitored the bit for when it turned off and saved the values in battery backed registers. Here are the parameters that I used for auto tune: (S3) - 500 (S3)+1 Set bits 0, 4, and 6 (S3)+2 - 10 (S3)+3 - 0 (S3)+4 - 0 (S3)+5 - 5 (S3)+6 - 0 (S3)+25 - 0 (S3)+26 - 4000 (S3)+27 - 0 (S3)+28 - 0 When the auto tune finished the values were saved in D400 to D406 registers. The saved values were: (S3) - 500 (S3)+1 Set bits 0, 4, and 6 (S3)+2 - 10 (S3)+3 - 20869 (S3)+4 - 331 (S3)+5 - 5 (S3)+6 - 829 I ran the pid for about 2 hours after auto tune. I set parameters: (S3) - 2000 (S3)+2 - 95 This seemed to stabilize the MV output value. I will post the finished code after I clean it up from the trials today. I wish to thank everyone that gave me so much help with this project. Thank you all, swimmy67

  8. Posted

    Well I was not successful in using the Auto Tune to obtain the values needed for the PID control. I used many different suggestions and even on from tech support in Japan through Mitsubishi Electric. The biggest problem is the Auto Tune never finishes. Yesterday I started the Auto Tune at 1:00pm and by 4:30pm the auto tune was still operating. I aborted the auto tune process and tried the valuse that I received from Colin. I am attaching the program to show the changes that I made from the original program. I hope all will ba able to learn from it and apply any further suggestions. Thanks to everyone that helped me with this project. swimmy67 FX3U_PID_Program.zip

  9. Posted

    TW, Setting the RTC is much like setting it in a SLC500. One way to set the clock is with the Function Files RTC tab. Click "Set Date & Time" button. See attached image. To load integer values from a communication or a move instruction the format is: RTC:0.YR for year. RTC:0.MON for month. RTC:0.DAY for day RTC:0.HR for hour. RTC:0.MIN for minute. RTC:0.SEC for second *(seconds are updated every two seconds)*. RTC:0.DOW for day of the week. Thanks, swimmy67 ML1100_RTC_Setup.bmp

  10. Posted

    TWControls, I wish to say thank you for the post for the ML1100. It is a great write-up of the trials of the ML1100 PLC. I wish that I could have done a project with the ML1100 but as of yet all I have is one sitting on the shelf. This PLC was intended to replace the Mitsubishi FX3U PLC that I am using on a current project. The PLC will be used on additional projects instead of the FX3U PLC. The Ethernet can be configured in RSLogix 500. Double Click "Channel Configuration" and choose Channel 1. I have attached a bitmap showing the parameters that I set to view the Web Server. I could not get our network to assign an IP address so I set it manually. Overall I like the ML1100 PLC. Granted it has its limitations but for what it does in such a small package it is a good choice. Thanks, swimmy67 ML1100_Ethernet_Setup.bmp

  14. Posted

    Colin, Thanks for the information. I will look it over and try and see if I can get it to work. The Honeywell Modutrol is used for Natrual gas flow in the Eclipse burner. Low flame to high flame control. The burner is heating cooking oil to 190 deg C. I am trying to control the burner with the PID function in the Mits PLC. So far I have not had any luck in controlling it correctly. I will keep you posted on the situation. Thanks, swimmy67

  15. Posted

    Colin, With the FX3U PLC the PID function is a little different than the FX2N PID function. There are added parameters that have to be set for the PID when auto tuning. FX2N PID has fewer parameters. The parameters are (S3) to (S3)+24. The FX3U PID has parameters from (S3) to (S3)+28. In addition the parameter (S3)+1 has additional parameters to set. Parameter (S3)+1 bit6 sets "Step Response Method" or "Limit Cycle Method" for the auto tune. When selecting Limit Cycle there are additional parameters that also need to be set. Parameter (S3)+25 to (S3)+28 also need to be set. The problem that I have is the PID not functioning as it should. I have set the Proportional gain to 10%, The Integral time to 60, Differential gain to 0, Differential time to 0. I set parameter (S3)+22 to 100, parameter (S3)+23 to 0. When the PID runs ,continuously of course, the output percentage does not maintain at a percentage between 0% and 100%. When the PV is low the output is 100%, when the PV is high the output is 0%. when the PV is at setpoint the output is 0%. Any ideas would be helpful. Thanks, swimmy67

  16. Posted

    Collin, Thanks for the reply. I have read the post and tried the settings but it still did not work. I personally do not think that the Mitsubishi PID is able to work for gas heating applications. All of the sample code that I found was for Electric heat and not for gas heating. The problem is for the PID to control the MV output from 0% to 100%. Every parameter that I put into the PID would not work. When the temperature is below setpoint the MV output is 100%. When the temperature is above setpoint the MV output is 0%. There is no in between. The PID will not control at say 20% to 30% when the temperature is near the setpoint to maintain the temperature. I have tried the auto tune to establish the proper settings but the auto tune would not finish. I aborted the auto tune and put in values that I calculated from the FX3U analog manual. Thanks for your help. Kari Swimelar swimmy67

  18. Posted

    I have been working on a project that uses the Inverter communication instructions, and the PID instruction in the PLC. The inverter communication was easy to setup. The PLC is communicating with four mitsubishi FR-E540-0.4K-NA inverters. When the PLC first starts, the parameters are loaded into the inverters via the RS-485 communication instructions. This allows the inverter to start, stop, and change speed. The PLC receives the status of each inverter to monitor if the inverter is running or there is a fault. What I am having trouble with is the PID instruction. The FX3U Analog Instruction manual goes in detail about the setting of the PID but it doesn't give very good information for the way I need to run the PID. I need to use the Limit Cycle method. Here is what is used for setting the PID: (S1) Target Value (SV) (S2) Measured Value (PV) (S3) Parameter (D) Output Value (MV) The PID uses 29 points in the parameter section for the calculation of the MV value. The setting values are from (S3) to (S3) +6. I am using D50 for the (S3) point in the PID instruction. This will occupy D50 to D78. For PID operation I am setting (S3)+1, or D51, bit0 to 1: Backward operation, used for heating. D51 bit5 to 1: Upper and Lower limits of the output values are valid. For the Autotune operation I set D50 (Sampling Time) to 2 seconds. D51 bit0 to 1, bit4 to 1: Autotune Is Exicuted, bit6 to 1: Limit Cycle Method. D52 (Input Filter) to 10%. D53 (Proportional gain) to 545%. D54 (Integral time) to 315 x 100 ms. D55 (Differential gain) to 0%. D56 (Differential time) to 787 x 10 ms. Limit Cycle parameters: D75 (PV value threshold) to 0. D76 (Output value upper limit) to 1000. D77 (Output value lower limit) to 0. D78 (Wait setting for end of auto tune) 100%. When I exicuted the auto tune, I let the instruction run. 6 hours later the auto tune was still operating. It was never able to automaticly get the parameters. Is there something that I missed? For the Limit cycle parameters, should I set D75 to something other than zero? I measured the actual PV threshold at 2.3. Should I input this value into D75? I am using GX Developer FX version 8.25B I am attaching the working program for review. This program is also a very good example of the Inverter communications. Thanks for looking and all of your help. Kari Swimelar swimmy67 FX3U_PLC_Program..zip

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  20. Posted

    Hi All, I have almost completed the programming of the FX3U PLC and the GT1000 touch panel. Here is the hardware that is being used: FX3U-64MR/UL FX3U-4AD-PT-ADP FX3U-485-ADP FX3U-USB-BD FX2N-16EX-ES FX2N-2DA GT1585-STBA I am connected to four FR-E540-0.40K-NA Inverters over RS-485network. Everything seems to be working. I am having a hard time with the Touch Panel getting things to display correctly and setting up message boxes. The GT1000 has a ladder monitor function built. You can upload the ladder from the PLC and view and make modifications from the touch screen. The PLC has enough memory that I was able to download the comments. I am attaching the working program. This is a new program that we are developing for our machine. Look the program over and see if you can see some peoblems or easier ways to do some things. I will accept all criticisms from all comers. Thanks, swimmy67 Kari Swimelar FX3U_PLC_Program..zip
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