drforsythe

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About drforsythe

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  1. Robot vibration

    There is an important detail that we must all know in order to begin helping:  Is this a new problem on an existing system, or are you just commissioning the unit for the first time?  If it is an existing system and the problem just started, you should look at what could have changed in the mechanical system (such as a loose or damaged coupling, or a change in payload or a program change that modified the speed or acceleration / deceleration).  If you are starting this system up for the first time, then the tuning parameters will need to be changed.  It has been a while since I used Mitsubishi servo drives, but I seem to remember an auto-tuning setting that described the rigidity of the system.  If you have this setting too high, but have a compliant mechanical system, then the motor will make noise at the beginning or end of each move.
  2. micrologix1100 explict message for power flex 525

    Please post a screen shot of the MSG block.
  3. can we control LN298 motor driver with PLC?

    The L298N is an integrated circuit, so a lot of us on this site are not going to be familiar with their use.  If possible, it is best to attach a specification sheet to help us help you.  A quick search shows that the L298N is a device that takes TTL inputs and drives inductive loads such as solenoids, relays and stepper motors.  That being said, the Q Series has output cards that produce TTL levels.  The manuals are available online.
  4. If I remember correctly, there is a box labeled "Replace Communications" on the download screen.  Make sure this box is checked.
  5. What is M code in mitsubishi qd75d4?

    Crossbow, that is not the way I understand it.  I was taught that G codes typically deal with the motion control aspect of a CNC and M codes deal with the canned functions like turning the coolant on and off or turning a spindle on and off.  I am not a CNC expert, but the motion controllers I have used operated this way.  A quick Google search confirmed this.  Maybe it is device specific?
  6. kaiser_will:   Thanks for the response.  I am trying to hone in on my spec by asking what is out there and for experiences of those out there.  My primary experience is control system design.  I have a call in to some reps, but I don't want to rely on salesperson advice only.
  7. What is M code in mitsubishi qd75d4?

    M Code is a standard instruction set for CNC machines.
  8. Hello All: Our plants are going through some expansion and the forecasts for more business are looking quite nice.  I have been tasked with determining where we stand in regards to available electrical power, chilled water capacity and compressed air availability.  For now, I am going to concentrate on the electrical aspect, but maybe there is a device that could cover all three.  I am looking to monitor the three phase voltage, power, frequency and calculate power factor on at least eight (8) main transformers.  I may decide to monitor to the bus level at a later date.  I would like a system with an OPC server that can serve this data to our OSI PI data collection system.  Regarding the chilled water system, I have four (4) systems to monitor. I would simply monitor set point (which may be manually set), outgoing water flow and temperature and return water flow and temperature. I have two air compressor systems to monitor.  For that, I would simply need pressure. I could always connect the sensors for the chilled water and compressor into a PLC and then connect our OPC server to that device, but for the electrical power, I would like something off the shelf.  Ideally, if I could have one device do all three, that would simplify things. If you have any experience with a device that would work, please share.     Thank you in advance.
  9. Controls Engineering

    I will offer this advice:  When designing controls, picture yourself in the position of the operator(s) of the equipment you design.  Try to think of all the ways that the process could fail, then design hardware and software that can help mitigate those issues.  If you work for a company that will allow it, spend some time working as an operator of the equipment you will be designing/programming/improving.  Build empathy for the daily users of the equipment.  If you can understand what it is like to be a daily operator of a machine or system, you can then make it friendlier to use.  Also, use your ears more than your mouth.  Listen to suggestions from those around you.  Being humble will earn you more friends than being cocky and thinking you know it all.  We all want to think that we are the best designers with the every detail thought out.  It is easy to get trapped in the pit thinking that our way of thought is the only, best way.  The truth is that people who regularly use the equipment know a lot and have valuable info to share.  By developing empathy for the users and including them in your design process, you will earn their respect and have allies when it comes to solving any problems that might creep up.  Classes are helpful, but not as helpful as fully immersing yourself into the situation.  If I had to suggest one class, it would have to do with communications.  Not the communications that deal with networks and devices, but interpersonal communications.  Learn how to communicate with the varying types of people you will deal with.  Sorry for the long-winded post.  Best of luck!
  10. Micrologix 1400 Post mortem

    You mentioned that it only made 300 parts.  Unless the output cycles several (hundred) times per part, it sounds like the load requirements do not match the output capabilities, as others have said.  If the inrush is too high for the plc output, place a socketed relay between the plc output and the load.  This way, if the relay fails, it is easily replaced and much less expensive than the plc.  Plus, then no work would have to be done on the plc (changing output addresses or downloading program to new controller).  If you still wish to drive the load directly from the plc and it is inductive, put an appropriate snubber on the output, as others have said.
  11. Request to Print ACD to PDF

    I just sent a PM to you with the pdf file.  I had to zip it to reduce the size.  Forum would not let me post as a reply due to size.   Good luck.
  12. Call ot Old Timers A0J2 & DOS MEDOC

    You should be able to completely clear it by removing the ROM, unplugging the backup battery (if installed) and removing power from the unit for at least 30 minutes.  It has been a while since I regularly supported Mitsubishi products, but their RAM seemed to be backed up for a long time using a capacitor circuit that allowed change out of the battery without losing the RAM.  Even though you have a ROM module, the program is loaded into RAM upon power-up.
  13. Call ot Old Timers A0J2 & DOS MEDOC

    Wow.  I haven't heard of that processor in MANY years!  One thing to think about:  Do you know what the plc was originally programmed with?  The dedicated programming units (GPP?) also known as the "big orange programmer", were widely used before the prices of PCs came down.  When I first got into this business, they were still quite popular - especially with the automotive plants.  The GPPs were able to access parameters that Medoc was not able to.  The biggest parameter set I had problems with were the MELSECNET/MINI parameters.  If a machine was programmed with a GPP and then someone used MEDOC to upload and download, the MELSECNET/MINI devices would no longer work.  The only way to get them to work was to add TO/FROM lines in the logic to set up the network.  The TO/FROM logic replaced the tabular settings available in the GPP. All that said, if the machine was set up originally with a GPP, there could be a parameter that Medoc cannot access and therefore give you a mismatch.
  14. control roon

    You should also explain what your goals are in monitoring these systems.  As kaiser_will added, comm options are important.  Some additional questions to ponder: - Do you want to archive the data, or just see the processes while they run? - Do you need to display alarm conditions? - Will you be using this as a monitor-only function, or will information pass from the control room to the processors? - Do you require some intelligence to predict how your processes will respond in the future? - Will you be programming from this control room?  If so, what firmware is in your CPUs? (This is important to know what OS you will use and if you need to have VMs installed to manage multiple rev levels of the programming software) - Will you need to be notified automatically via text message or email if an alarm occurs?
  15. Looking for programmer help

    Just sent a PM to you with a suggestion.