drforsythe

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Posts posted by drforsythe

  3. Posted

    I have seen the B&R stuff in use mostly on molding machines. We have two major brands of injection molders in our company and both use the B&R platform. We are not able to view code, so I cannot speak about the programming environment, but the hardware has seemed pretty solid. I also liked the statement "IMO you can't really design good software in ladder anyway". It made me chuckle.

  4. Posted

    I remember seeing a device just as you describe. It was a "packaged solution" for verifying that screws or nuts were tightened in the correct sequence. It was recipe driven so doing multiple parts was not an issue. Like I said, it was several years ago, and I cannot remember the name of the manufacturer. I did, however find a similar unit. I have no experience with this one, so I am not endorsing it. I am just sending you to their site for a reference in case a purchased device would be feasible. the website is www[dot]mountztorque[dot]com. I am not sure if you are quoting a machine for a customer or if it is for your own use, but a purchased solution may save you time, development costs and ultimately keep you more profitable. Let us know how you do.

  8. Posted

    Balluff has an inline signal conditioner that is designed to be used with switches like proximity and optical switches. It can be taught to act as an ON delay or an OFF delay with an adjustable time. This product would probably work in your application. Other manufacturers of industrial switches have similar devices. The Balluff unit is known as a "Signal Adapter BOS S-T". Info for this device can be found on their website. If you happen to have a Balluff catalog, it will be in the 'Accessories' section. Does your cutoff machine have a controller in it? If so, you could modify the program to only act on the positive transition of the switch. I am sure you have already thought of that and are looking for an alternative, though. Hopefully this is helpful.

  10. Posted

    If loading using straps or chains and a hoist (which you probably are), a spanner is definitely the safe way to do it. Nylon straps work better than chains. Once the Hoffman hooks are in place, they typically do not move if the even tension is applied to each hook. Another option could be magnets if there is room on the subplate after assembly. It is common to move large steel plates using this method. The lack of open panel space after assembly would probably not allow this, though.

  11. Posted

    Hoffman Enclosures has panel lifting hooks available. The catalog number is APLH. The catalog does not state the maximum load, but we use these to place large and medium size panels into the enclosure and onto the studs. Check out www.hoffmanonline.com for more info.

  12. Posted

    We have systems in-house that utilize a "brake override" to allow maintenance of the axis. It utilizes a normally open relay contact (as described above) in parallel with the contacts for the safety and monitoring circuit. The coil leads are run to a connection point where an external power source is connected. The external power source has a momentary pushbutton in it to allow power to flow to the coil of the oveerride relay when pressed. The connection point utilizes a connector to make connections easy. We store the brake override power supply in a separate location from the machine where only our Maintenance or Engineering departments can access it. BE CAREFUL DOING THIS ON A VERTICAL AXIS, THOUGH! Doing this on a vertical axis requires a good procedure and proper devices to control the descent of the axis when the brake is released. You may want to think about how you would do that on your machine (blocks, slings, crane, come-along, etc).

  13. Posted

    A standard way to do this is to use a brake that must be energized to release. You would then create a series circuit for the power for that brake. The series circuit would include your safety circuit (MCR or safety relay), the fault output for that axis and an output from the servo drive that is active when the servo is enabled. You may need to use relays on the fault output and enabled output, if they are not already contact outputs on the servo drive. This way, if the safety circuit is not enabled or there is a fault on the drive or if the servo is not enabled, the brake will clamp the motor shaft and not allow it to move. Depending on the application, you may need to use a safety relay with a time-delayed output for control of the brake.

  14. Posted

    If I were in your position, I would start by taking an inventory of the controls equipment that I would be responsible for. I would record model numbers on all PLC CPUs, I/O cards, analog, motion, network or other cards in the rack. I would also look into the types of human machine interface products. If you have drives, record them also. Then I would check to see how all of the stuff on the equipment "talks" to each other (digital I/O, ethernet, MelsecNET, CCLink, serial, etc). Once you have an idea of all of this, I would ask your local Mitsu rep for a list of classes that might assist you on your journey. Depending on your troubleshooting and other electrical skills, you may also want to look into some general classes. The bottom line (as you probably learned long ago) is that the classes will give you the foundation or starting point. Old fashioned, hands-on training will get you the farthest. I hope this response was not too general for you. Take care and best of luck!

  15. Posted

    I agree with kaare_t. We need more information. As an alternative, have you tried getting your local Mitsubishi office or distributor involved? If they are too far from your location, there may be a local integrator that they can refer you to.

  16. Posted

    If you have replaced the drive and card, did the correct parameters get loaded? A little more info on the hardware might be helpful as well. You might also want to say where you are located, as one of the talented people on this site might be able to pitch in some on-site help if properly per$uaded.

  17. Posted

    Does this fault occur only when you stop the motor, or when it is commanded to run? Does it ever happen when the motor is sitting still? Can you connect a meter or recorder to the output of the drive? You could monitor the actual voltage on the motor leads when the motor is stopped. If the drive is in a stop condition but voltage is present, then it is indeed regen. An alternative thought is that you may have a high input voltage condition. The high input voltage will cause a higher DC bus on the drive. When the DC bus gets high (either due to regen or a high input voltage), you will get an F05. If your incoming power is high, you can suggest gathering more info on the power supply. If it is always on the high side, you may need to change the tap on your plant's power transformer. If the trips occur only at certain times of the day or night, then it could be the power company switching their power factor correction capacitors. If it is a slightly high power or from a fluctuating incoming power, a line reactor could be added to the input power side of the drive (if not already equipped). Sorry for the brain-vomit- I just typed issues that I have seen in the past with variable freq. drives.

  18. Posted

    RussB: We understand the risks of buying such equipment. We have a problem to solve in order to make a more manufacturable and easier to use product that this machine can help with. The machine was purchased to be used as a research and development project. We knew full-well that the machine was inferior to anything we could design and build ourselves. However, the machine was a standard piece of equipment, readily available and already doing some of the features we need at our Chinese manufacturing facility. We will be taking the lessons learned about our process needs and the existing machine to create one that will fully meet our needs. If anyone is interested in hearing about the shortcomings of this machine, I can show you the list we generated prior to ordering it when we justified the cost. Guess what? The cost was still justifiable even with the changes. Will the machine run 20+ years with no issues? No way, but it will run long enough to suit our needs. That being said, hopefully I can get a response from someone who can source me the software so I can correct the spelling mistakes and streamline the screens.

  19. Posted

    All: We recently purchased a very inexpensive cutting machine that utilizes an operator interface touchscreen from China. The manufacturer is MCGS and the part number is TPC 7062KX. Do any of you know where I can get the software for this? I have done some web searches, but most of the hits are Chinese websites with no English text option. Any suggestions? Obviously, I can convert to another manufacturer, but the purpose of this machine is R & D, it was low cost to develop a process. The machine is not a long-term solution to our problem, so I don't want to convert at this time. Thanks in advance for any input you may have.

  20. Posted

    Check for a good ground for the vfd supply and make sure the motor is grounded at the vfd ground connection. I have seen this before. I have even seen a drive show this fault when the motor was not commanded to move and the motor de-energized. The drives are set up to protect both the motor and vfd. Sometimes this sensitivity can lead to nuisance faults. I don't guarantee this is the problem, but I have seen this problem disappear after ensuring good grounding practices were used. Good luck, Derek

  21. Posted

    Are the inputs and outputs that you wish to use already in your system (spares)? If so, are they on the main rack or on a network node (like Flex I/O?) If they are on the main rack, then locate the rack location and I/O point in that slot. (All slots are numbered starting at 0 (from the left). If it is an input, the address will be Local:x:i.data.y, where x is the slot number and y is the input point. For outputs, the numbering is the same, but replace the I with an O.

  23. Posted

    What type of acceleration setting do you have? Also, what mode are you running the drive in? If it is set for DTC (direct torque control), then you will need to let the drive do and ID Run. This sets up the DTC settings. If not set properly, the motor will not perform properly. See the manual.

  25. Posted

    This happens to us occasionally when our annual negotiated pricing expires. You get what you give out of your vendors. If you simply place orders when you need something without reaching out to your vendors, you may get pricing that is close to list price. Our AB distributor is fantastic. They help when needed and stay away when I don't have time. I keep them posted on my projects and they keep me up to date on new products and technical issues. I recommend checking out your available distributors and finding which one can give you the best LONG TERM bang for your buck. You may find that once they get to know you and the potential your company has to their bottom line, that you can get good discounts AND good service.