plastic

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  1. Frustrations

    PLC 5 (1771) Analog modules typically have HARDWARE configuration jumpers, and SOFTWARE Configurations that are written to the card once during PLC first pass power up. Blindly swapping modules without confirmation of hardware jumpers being set to application design, can lead to unsafe machine operation. I also would not expect the module to operate correctly as the configuration file probably won't be written to the module during a HOT SWAP. Tell your boss that you will do it your way, (following the rules and instructions), and if that does not please him, let him do all the "hot-swapping", and he can incur the unhappy results of doing so.
  2. Panelbuilder32

    Most systems integrators merely create a PBA PanelBuilder Apllication, then compile it to a PVA, PanelView application, and then download it. This is all by default. Then after than, any one can upload the pva, decompille, and edit. There are (2) different scenarios that will will inhibit future uploads. If the originator is trying to protect thier intellectual content, they may elect to make the PVA so that it can not be de-compiled. The second scenario, is one that we ran into, is that if your application exceedes hardware memory limit, you can elect to make the PVA not de-compile, and eke out a few more screens.
  3. RSlogix 5000 and PIDE

    mplummer, We have integrated CompactLogix control retrofits of injection molding machines. You are right; an improperly tuned PID will have massive overshoots at cold-start. This is typically due to integral wind-up. The construction of injection molding machine barrel is where electric heat is applied to the "skin" of the barrel, but the measuring point (thermocouple or RTD) is typically buried to the core. This physical installation has a large thermal lag time between when heat is applied, and heat reaches the measurement point. Small machine = small problem, big machine = big problem. We migrated away from standard PID to PIDE. There is an AUTO-TUNE feature to the PIDE. We used the auto-tune and experienced satisfactory results. VERY IMPORTANT NOTES to consider: 1. You will NOT decrease the cold-start time using the programmable controller alone. 2. The heat up to temperature without overshoot required time is dependent on the existing physical installation. 3. Auto-tuned PIDE will allow you as the integrator to get the fastest response without over-shoot achievable with the existing physical installation. 4. Make sure each heater band is functioning in each heater zones. You can do this with an IR image of each band, and amp draw measurement on each band, or simply touching a sprue of plastic to the exterior of the band during heating. It is VERY important to have 100% healthy heating zones, prior to the auto-tune, to obtain the best results. Check the AB web-site for documents relating to auto-tune application examples for PIDE. We actually incorporated auto-tune on engineer accessed screens at the HMI for our convenience. Here is an overview of how the auto-tune works. It is absolutely mandatory that the thermal load is at a steady state. On a large injection molding machine, this typically is only after the barrel heat has been turned off for about 24 hours. If you invoke an auto-tune, you will only have one shot at it in any 24-hour period. The key reason for the barrel needing to be at steady-state (room temperature) is so that accurate data measurements will need to be recorded of system dynamics and capabilities during the tune. Auto tune steps. 1. Set each zones manual output to 0.00%. Set each zone to expected run time temperature (several hundred degrees above ambient) 2. Set each zone to MANUAL mode 3. Turn on all zones. They will sit at 0.00% output 4. Enable all zones to auto-tune The auto-tune feature will go on-line with each zone, and ensure there is a "steady-state" temperature, (neither rising nor falling). About 30-60 seconds later the auto tune will kick the output to your pre-defined max output level, (we used 100%) The auto tune will then internally start a timer. The auto-tune will be collecting key information about the dynamics of each zone. The first thing the auto-tune will document is the time from the start of applying heat, to the time heat is seen at the point of measurement. This is the "thermal-lag" time. The auto-tune will also find the "slope", or rate of change actual with a known percentage output. On a typical injection molding machine when several zones are auto-tuned simultaneously, the nozzle will finish first. (Least thermal mass). The center sections of the barrel will typically finish tuning later, (up to 10 minutes on a 2,000 tone molder, and the rear zone most likely will finish last, as it has the throat pulling heat away from it. Once all of the zones have auto-tunes complete. The auto-tune feature returns (3) set of suggested PID parameters. (Slow / Medium / and Fast). We could often use the Fast parameters, but if your IMM is 3,000 to 4,000 Ton, you may want to use medium gains. Once we read the auto-tune returned suggested PID parameters, we would enter those into the PIDE. We were quite satisfied, as we were using MATH, and not "tweaking" to achieve a "tuned loop". How do you know if you have done a job? It is important to collect data BEFORE tuning and AFTER tuning. If you have an HMI with trending feature, you should be able to graphically plot the temperature approach to set point before. (Sluggish? Aggressive, but with overshoots that take hours to recover?) Then after the auto-tune, and using the suggested parameters, you should graphically see a confident temperature approach to set point with minimal overshoot. Again, You will NOT be able to heat the barrel any faster by pushing buttons alone. The key takeaway here is that you will have the best values to heat-up and maintain the barrel temperature for molding operations. With SSR control of electric heat you do not need to have a MAX on of 15 seconds. During cold-start the outputs will be held on until the PIDE throttles back. SSR's can be switched frequently, I suggest a (5) second period for your main barrell zones, and a (2) second period for your nozzle zones. ie 50% CV for barrel would be 2.5 sec on and 2.5 sec on. 50% CV for Nzzle would be 1 sec on and 1 sec off.
  4. I was defragging, and looking around under the hood of my company laptop. When I went to Contol Panel\Add Remove Programs, if I SORT by SIZE then "Rockwell Software Hardware Maintenance Tool" shows up as the BIGGEST HOG at 992mb. What is it? Can I remove it? We use: RSLogix 5000 RSLogix 500 RSLogix 5 RSLinx RSView ME RS Networkx Panelbuilder and blah, blah, blah But if I press Start\Programs\Rockwell Software\... I can't even find "Hardware Maintenance tool????
  5. CompactLogix 1768 and IAI

    For RS-232 control from a Micrologix, we have always used these instruction. AWT - ASCII Write (Your ascii strings sent). AWA (Your ascii strings sent, with an appended LF and CR), and lastly a ACL ASCII Clear Buffer - We turn this on when no data is being sent, this allows you to plug, and unplug RS-232 equipment, and keep any stray garbage bits from coming into the receive or transmit buffer of the PLC, and then hanging up the next desired ASCII WRITE to the destination device, due to garbalage. That's it for simple RS-232 ASCII type devices.
  6. And another caveat..... We just integrated (10) Microscan QX-830 Ethernet scanners to a Compact Logix. I used the Microscan document that you posted. It works just as they show it in the document. You will notice on the last page of the document (in the blue highlighted box), that the ASCII characters come in broken up into each individual character, and in NUMERICAL value. You only see ASCII character if you toggle the TAG monitor to display ASCII. NET RESULT: We had to overcome two minor hurdles. One - Convert each numerical value into a true ASCII character Two - Get the segmented characters into one contiguous ASCII string. (for subsequent compare to static strings) I spent one whole day on it, and came up with a robust solution to convert, and concantenate. (It did require creating a static ASCII look-up table in the controller). We are successfull with our integration. PM me if you would like a word.doc of what we did in RS Logix 5000. If you get over the initial Ethernet issue.
  7. CompactLogix 1768 and IAI

    Fire up the original controller. Connect a laptop (in place of the IAI), use HyperTerminal on the laptop to capture ASCII data (commands) being sent by the original controller. Now connect the same laptop to your new 1768 controller, use HyperTerminal to capture the ASCII data being sent from your new controller. This should allow you to easily see if you are adding or ommiting succinct command punctuation.
  8. SLC 5/03 has a port that can be configured for ASCII writes to a RS-232 serial device. What are your label ("ticket") requirements? Paper? Self adhesive label? Label pulled and installed by operator? Label installed automatically by printer? Check out Zebra printers. They can be oredered with RS-232 interface (old-school) but compatible with SLC 5/03. They can spit out a label, the have "print-and-peel" funcitons where the operator grabs a label and applies to the product. How many labels per minute do you need? The ladder code is relatively easy. You can use RTC integer data, and convert it into STRINGS, and then concantenate (add to) static strings, and generate labels. You will need to have static ASCII control codes as part of your RS-232 ASCII write to tell the printer what to do, (font = arial / font = barcode), and also control codes to actually print the label and "form-feed". If you detail your requirements more on the forum, somebody here (inculding me) can send you a sample .RSS file to get some ideas from.
  9. Glad I work in Industrial Electrical...

    The same guy that wired that basement has a day job also, I came across his "handy-work".
  10. Wiring Schematics

  11. Please resist the urge to "story tell" or share a story your heard. No "hearsay", "what happened to me", or "story tell", but a link to another documented incident. http://www.hss.energy.gov/csa/csp/aip/acci...AC_20041011.pdf
  12. PLC Law

    PLC Law 43.1 [43.1 2014 EDITION] The PLC can allways be programmed to overcome any axis (or process) problems where NO sensors exist.