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Mick

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Everything posted by Mick

  1. Thanks Joe for the advice, The PID work well now. I think the problem was that I was not using the full range on the PID input, and moreover there was noise on the measurement due to the proximity of the power converter. I use the full range with a little numeric filter on the 4-20mA converter. It works well with good accuracy. Mick
  2. Sorry for the response time, I was working on another project. Yes my file is to big (0.56MB), : "Drag files here to attach, or choose files... Max total size 0.01MB " I understand that it would be easier with the code. I would have preferred also to send it to you . For explain the context, i use a PID loop to regulate the voltage of a battery charger according to the battery voltage. There are different components between the charger and the battery (cable, diode etc ..), so a voltage difference according the current, temperature etc.. . Using a PID loop would ensure a accurate voltage setpoint on the battery terminal whatever the conditions. For the answer : 1. What is the model number of the Samba? => SM35-J-RA22 2. Which physical input is this PID loop connected to? => The physical input is a battery voltage. The nominal voltage could be 24V or 48V ( Wherever possible I would like to make a single program for both configuration 24V and 48V) => for the 24V : the min voltage is about 20V (at the end of the battery autonomy) the max voltage is about 30V (During a boost charge) => For the 48V : the min voltage is about 40V (at the end of the battery autonomy) the max voltage is about 60V (During a boost charge) => So i use a 0-100V / 4-20mA signal converter for the input measure. The linearization is : X1=3273 / Y1=0/ X2=16380/ Y2 = 10000/ X=MI1 / Y=MI247 3. Which physical output is this loop connected to? => The physical output is a 0-5V signal for controlling output voltage of a 24VDC or 48VDC power converter ( Use for power supply and battery charger). The response of the power converter is for 24VDC power converter 1V = 9.6VDC / 5V=30V, and for the 48VDC power converter 1V=19.2V /5V = 60V => I also use a signal converter for the output because i need a isolated signal. it's a 4-20mA / 0-10V converter 4. You said the input is 0-100V. Is this being scaled somewhere else? => Response at §2 5. You have the output range limited to 1700-2400. Is there a good reason why? This is way too tight. => F or the operation i would prefer stay between 20V to 30V for the 24V system and between 40V to 60V for the 48V system => So i use a 4-20mA / 0-10V signal converter then the output range is about 1700-2400 , corresponding about (if i don't make a mistake) at 20V-30V (24V converter) or 40V-60V (48V converter. 6. Is the analog output being scaled somewhere else? => Response at §3 Michaël
  3. OK, i did not know the PID could work without auto-tune. I'm a beginner in programming... I will try manually. On the attach : - The first : i recorded the image when it worked a few day ago. Now the PID status stay at -11 - The second : The PID status stay at -2 (Control value go and stay to high or low limit)
  4. Hello, I use the PID with autonune of the Samba PLC. It doesn't work well and i don't understand why. That is my hardware set up for PID : => analog input is 4-20mA (voltage measure 4-20mA : from a 0-100V / 4-20mA converter), => analog output is 4-20mA. ( control voltage 4-20mA : to a 4-20mA / 0-5V converter) At first the PID status stayed at -11. I've read on the help file that it's could be the noise at the input, so i follow the advice by increase the high limit and decrease the low limit on the PV input. After tying a lot of different setting the autotune then PID finally works. Now, i try an auto-tune and it doesn't work anymore, two situation : - I set a wide range in the PV input : the control value go on the max value or the min value, the PID status stay at 2 - I set a smaller range in the PV input : The PID status stay at -11. For information i use on the Samba the 4 analog input, and the 2 analog output. Could the problem come from the speed between the input and the output? I need help. I try for several day to fix the problem, but i still no understand and I'need PID function on my project. My program file is to big for attach. Mick
  5. Hello, On my project i would to choose the alarm name on the digital input I0-I1-I2-I3-I4-I7-I8. On the attached file : ladder "Alarm display" and the HMI "activ alarm" On the data table "alarm name 2" i created 7 column, on each column there is 16 rows for the alarm name possibility. For each columns i increment a MI for read the row. I choose for each column the alarm name. It work, so : what I can not do : When I0 switch, i would read the cell corresponding of the position of the MI. For example : MI column1 at 0 => When I0 switch i would read "Arret d'urgence" MI column 2 at 10 => When I1 switch i would read "Défaut temp" MI column 3 at 14 => When I2 switch i would read "Défaut réserve 3" Etc... How i can do that? I don't understand how to link 2 data table. Thanks for the help. Michaël pgrm V1 20171107.vlp
  6. Hello Henny, I do not remember having made a mistake in the Ladder. I just used the FB modbus as in the example. Yes, I tried several times to repower the plc, but still the same message in the event log: "Send break signal" ect... I'm not really sure, but I think rather a bad manipulation of Realterm (this is the first time I use it) in Modbus. Michaël
  7. It works now! For information, that's what I did: - enter Info mod - Push on "Working mode" - Push on "Exit to factory boot" - the screen turn red, and at this step i send a new program from visilogic to the PLC - Communication was done correctly Thank you for your help. Michaël
  8. Hello Henny, Thank you for the answer. I was in the infomode, and there is no communication even in stop mode. I also tried with a new empty program, the connection is not possible. There are always the same messages in the EVENT LOG: - "SEND BREAK SIGNAL" - "UNABLE TO SYNCHRONIZE - PLC COMMUNICATION PARAMETERS CAN NOT BE SET I had never had the message before. It appeared after the use of Realterm to try the communication in Modbus. Is there a possibility of knowing where the problem comes from? It's a problem coming from the PLC or the PC? Michaël
  9. Hello, Since yesterday, communication between the PLC Samba and visilogic no longer works. I tried another communication port, another PC, a USB / RS232 emulator and still no possibility to connect. This happened when I was working on a MODBUS example. it is always the same message (see attached files) I do not know what to do. Could a reset of samba plc solve the problem? Michaël
  10. Ok, I did not understand what the store function was used for. Thank you!
  11. Ok, i undersatand , but don't find a buffer MI. Could you tell me what is a buffer MI?
  12. Hello! I make a program for a battery charger. For charge the battery i need two voltage level (Floating at 270V and Boost at 276V) : The piece of programm is in the attached file. I use two set point ( I can increment or decrement the two set point on the screen) : - MI20 : Floating voltage set point - MI22 : Boost voltage set point Then, i use a SUB function to obtain MI4 : the difference between MI22 and MI20 Next , i use a ADD function to obtain MI23 : The sum of MI20 and MI4 The MI23 is linearized and send to the analog output MI21 This doesnt work because the out of the math function not include the state of the bit MB 31 at the input. In fact, i would send 270V (MI22) to the analog output when the MB31 is off, and send 276V (MI20) to the analog output when the MB31 is ON. Would anyone have a solution? And sorry for my english!
  13. Hello, I use a Samba HMI for control a power supply, and i begin on visilogic. I send a setpoint to analog output for voltage and curent and I would like protect the setting with a password. I've try the variable "numeric password", but i don't know how to link the password to the button. The screen is on the attached file. Would anyone have a method to protect access to the settings? Michaël
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