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Panagiwtis

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Panagiwtis last won the day on November 22 2014

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  1. So, after all, what solutions i've got now, except changing the expansion card or moving the VFD away from the PLC? Any suggestions?
  2. Thanks for the reply. At the moment I haven't the final electrical drawings on hand but I think that the 0V signal of the analog output is connected to the 0V, but I have to discuss it with the electrician that made the wiring. At the moment I am many kilometers away from the plant, so I can only assume things. The main thing is to make sure that IS NOT a bug of the program...
  3. That's exactly what's happening, the inverter works in the minimum 25% and in the HMI screen shows that it works 100% (as it should from the PID), and the tag related to the output has a value (4095), but the PLC sends 0V to the psysical output. Any suggestions?
  4. Thank you for the reply, I have a similar pdf named "System Wiring Guidlines" but it seems that the one you posted contains much more info which I am about to start reading it now. The thing is that I am facing the exact same problem (with the exact same expansion card) as described in the first post here --->http://www.unitronics.com/forum_old/topic.asp?TOPIC_ID=137 Any opinions and suggestions are more than welcome because I am trying to prove to my supervisor that I am innocent and its not a "bug" of the program, because in the tags monitoring I can see that the MI that is related with the output has a value and the same time the voltmeter reads 0V...
  5. I have a serious problem with V200-18-E2B (connected to a V570) that controls the inverter (GRUNDFOS CUE) of a pump via an analog output (0-10V). We are talking about a cooling system and I am using PID in order to control this analog output. The process value is a temperature sensor and the control value is the MI that controls the analog output (after Linearization) that goes to the inverter. When the PID is not active I use a strore direct function that stores the number 300 (30%) in the MI. The problem is that sometimes while the system seems to function normally, the HMI correctly shows that the inverter is working at 100% and I can see in the visilogic that the current value of the output MI is 1000 (100%) and 4095 in the real output (out of linearization block). However, in reality the inverter is working on its minimum safety setting (from its manufacturer) of 25% and when I measure the analog output of PLC with a voltmeter, the reading is 0V!!! I can't figure out why this happens, this problem drives me crazy and its a disaster for the customer...... Please, I need some help to find a way out of this..... PS1: I am not 100% sure but I think (i am many kilometers away from the plant at the moment) that this happens only when the system has made a complete cycle, the user has made a shut down to the system and restart it after this first shut down. PS2: The inverter sits inside the electric control panel and it's near the plc. Could this create a problem like this, or I can exclude that because of the fact that the problem doesn't occur all the time?
  6. Couldn't agree more, definitely these are the top 3 disadvantages of Visilogic. No change, even in one of them till today about three years later...
  7. Hello to all, I have this project that my supervisor wants to control the inverter (model is GRUNDFOS CUE) of a pump that supplies with cold water a tank. I want the plc to be able to control the revs of the motor proportionally with a setpoint (temperature) and send more or less cold water to the tank. I think that this can be done via a PID control loop, but I don't know the way and I couldn't find any related examples or topics in the forum. Has someone any experience with similar system or any clue how to achieve this? Any suggestion is more than welcome.
  8. Sgull, in the second screenshot in the first comment line you write: "Use MI3 value for a totaliser", but I can't see any MI3 in the ladder... I suppose that you mean ML0 instead of MI3, is this right? I imagine that totaliser is the one I want to display in the numeric variable in the HMI, isn't that right?
  9. Sgull I can't thank you enough for your response!! That seems to be the way to do it, I have to examine it more thoroughly but I am very confιdent that this is the solution to the problem I am facing. If this is any further help, the energy meter is from Schneider Electric and is model A9MEM3110.
  10. Hello EduMarg and many thanks for the reply. The problem is that according to the electrical scheme, the energy meter appears to be connected to a digital input of the plc, not an analog one. So , if I understand correctly your post, there isn't any linearization to be done...
  11. Hello unitronics community, I am relatively new to unitronics plcs so forgive me if the problem I am facing is ridiculously easy to solve. I have a project that includes an energy meter, that is connected with one digital output in the V200-18-E2B expansion card (connected to a V570). I would like to display in a screen of my V570 the energy consumption in kwh via a numeric variable. I know that I must use pulse in order to do that, but at this moment I can't manage to find a way to achieve this. Any help? Every suggestion is more than welcome...
  12. Thank you all for your answers. I thought that some kind of system bit existed for disabling touch screen. I believe that the simplest way is to create a blank screen and call it for some amount of time with the use of a timer. Kikisf20c: Geia sou Patrida. Mipws eisai apo Lamia meria?
  13. Hello , first Unitronics experience for me, many hours of watching webinars and reading about. I couldn't find how to make a button called ""Clean Screen" for instance that when is been pressed, the screen will freeze for some amount of time in order to clean the surface of the screen from dirt, dust etc. Any suggestions? Thanks in advance.
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