Shiner

MrPLC Member
  • Content count

    297
  • Joined

  • Last visited

Everything posted by Shiner

  1. 231 RTD

    We have a spec sheet for a em 231 analog input rtd 4 input module. It only shows four wire RTD terminations. Is it possible to connect a two wire RTD to this module and if so how is this done properly. 6ES7 231-7PC22-0XA0
  2. DL05/06 programming questions

    Being efficient with code is something that can separate a good programmer from a great one. Prior planning with truth tables and flow charts can help in this. It also helps to remember your boolean logic and reductions (I assume you have this since you said you have a computer programming background) to make the most of the steps in your logic. Too many times I have looked over a program and found that either there is redundancy in the logic, or functions can be used in the place of several rungs of logic. Like the DRUM function in AD to replace a sequence of events. Also if you get into any high speed applications, it is good to know all these things and plan ahead of time so that your structure is proper. It does not seem to get enough mention in this forum but if you have things out of order (this often occurs by programming on the fly) your program may do unexpected things. I ran into a situation helping an associate where the machine would not function correctly. Turns out the time base he was using to determine the sequencing was derived from timer X and the reset from timer X occurred in the logic before the compare statement that determined the output. The last step needed to see the timer done bit. Due to program size and scan time sometimes this would occur but other times not. Also as I mentioned he had a longer scan time than was necessary because he had repetitive logic. Again the truth tables. If A & B & C = D then don't reuse A & B & C, use D. It is a resultant of the and statement and therefor a logical minimized equivalent. I really have found that if you think of your basic structure from a logic standpoint, nothing more than a bunch of and or gates ect, then programming in any software family becomes just a matter of finding out what they call each component.
  3. AB vs Siemens

    I don't mind personal opinions, I have my own on alot of things as well. It seems to me that siemens is very much like most of the german people I have met. Very much about I am going to do this one thing, and now I am going to do this next one thing, after that I will do that one thing, never really multitasking, but efficient the same. I do not mean this in a bad way, I have several close friends that operate this way and often it gets results. I have found in learning many different software applications that each has its own set of features or styles, and often those can be used in all apps once the interpretation of each style is understood. Not sure if I am being clear here but for instance, you can take the way AD drum sequencing works, and apply it to AB, Eaton, Mitsu ect once you know how the drum sequencer works. When it is broken down into its elements, those elements can be transferred into any language. I believe learning siemens this will be true as well.
  4. Have an input from a relay that is held by outside power source....run a timer off of that that will initiate your shutdown...
  5. AB vs Siemens

    Thanks again, still learning the siemens side of things and their website is even more segmented than AB. Does anyone else find that these sites are a chore to get the information you are looking for. I am now trying to find data on cabling. I have a 226 processor and a 6" basic touch screen both have the serial port. I have not been able to confirm the wiring pinout or any recommended part numbers. Is there a resource I am missing or a link on their site that will give me that info?
  6. AB vs Siemens

    yeah I have heard the two platforms are as similar as micrologix is to contrologix....same family different features. One of my biggest concerns is the HMI integration. I have worked with AB Eaton, and Mitsu, but not Siemens. Any pointers or resources, similarities to anything I am familiar with would help. Thanks again.
  7. AB vs Siemens

    Thanks for all the advice. I have been working with the 200 series cpu for some time without much trouble, but also without much in the way of a challenge. I know the end user has all AB in one building, this is actually in a different building and the customer already sent them their spec sheets calling for Siemens without any negative feedback. I looked at the 1214 cpu with a 6" color. The only unknown here for me is the communication between the two as far as how tagging works on this platform.
  8. 2 vfd, 1 pot

    The Yaskawas are good for this. On one drive input your 0-10 to V, A1., and AC respectively, program the analog in for 0-10, set reference parameter b1-01 for terminals, set speed ref max and min for analog in and then program the analog out (AM and AC) for 0-10 and then set h4-01 to whatever suits your app
  9. 2 vfd, 1 pot

    There are a few ways to do this. Some work well, some don't. What is your app and drive type. There are drives that can be set as followers in which case you set up drive 1 to read the input (0-10?) and adjust speed accordingly, and then output a signal to the other drive telling it what speed to run. When running two in parallel, you can have voltage fluctuations if the circuit is not designed properly. You should use an external supply, so that the reference is common to both drives and a variance in a power supply from one drive to the other will not cause one to be always faster than the other. Again, it would be easier if I knew the installation and drive type.
  10. Drive Fast Stop

    Is this with or without load. Yaskawa has a stop function on some of their drives that reduces braking time by up to 50% under load over dynamic braking, I can't remember what it is called. I read some of the tech notes on the eurotherm method and it sounds like a similar concept. Realistically, with the way an AC motor works, if you have a large inertial load and plug the motor with enough current it will stop very quickly. It may not do this more than a couple times. The downside is heat, and depending on the manufacturer and type of windings, if the insulation is not bonding the conductors well, short circuit current will cause a conductor to actually move. This is amplified by the number of conducters in the coils, and they all begin to vibrate against each other. Add the heat, the friction of high current situations, and this is a recipie for major failure. You can have drive parameters oversized to do many things to a motor, including shorten its life.
  11. PID

    That sounds about what I was thinking except for creating seperate routines. The main thing right now is, not having alot of PID experience with contrologix, how to set up the smoothing of the incoming signals. They aare very dirty, even though the cabling is shielded in conduit, I see the count jump quite a bit. My cvoncern is it could jump to a high point and set that as the target, and forever chase a point that was nothing more than a spike.
  12. Tag Name Change

    Thanks, Yes you are both correct....most of the tags in the HMI are not affected, it is just a processor name change. There is one tag the customer specified that reflects the processor name and is used for alarms and watchdog configs. I was in quite a hurry and have alot on my plate (like most of us) and initially was nervous this would turn into a big project.
  13. I am nearly finished with a project that involves two systems, each with an L63E and Panelview 1000. The customer has just come to me and requested a name change to the PLC, acknowledging that the tag names will have to be updated as well. Is there a shortcut to this or do I manually have to go through and reassign all my tags on my HMIs.
  14. what platform, drive, analog inputs are you using?
  15. I suppose it could do some protections, depending on how you are using the drive. If you use one of the aux contacts on the drive and set it up so that the contact closes when the drive is outputting full rpm of the motor, but I don't see it as an advantage. Most of todays drives have multiple types of protection built in, making the need for using the E3 for protection redundant and an added headache to set up. If it were me, I would use the drive for all the protections and the E3 just as a monitoring tool.
  16. 24 HOUR COUNTER

    Thank you that is perfect. I understood that there was an incremental increase, and that it causes accuracy problems, but I did not see what your function was accomplishing. Now it is perfectly clear and thank you for sharing a very simple method of coping with scan time delays.
  17. 24 HOUR COUNTER

    If T4:0.acc is greater than 1000 then increment a seconds counter and subtract 1000 from the .acc. I have read a bit of the posts on this and I know that the end result of a timer running its course and being reset is a value greater than the timebase you set so incremental increases (deviation) in used time occur, but the explanation for why what you have works still is not clear to me. Why subtract that value from the timer. Is the math function faster than the reset function? Isn't there going to be deviation already, you are not performing the math when one second is reached, the expression is when it is greater than 1000 (1 second)
  18. Fuse

    In regards to the second drawing two things. The fist example shows a motor feed that is of lower current rating than the main feed. This is a simple protection of the motor from overcurrent (the line will supply way more current than the motor can handle). However, I see in the notes that the disconnect is rated for 30A yet the wire used is 14awg. The standard here (again I know you are in a different country and standards may be different) for 30A is #10AWG. putting 30 amps through a 14 guage wire will make some heat when it is a load such as a motor. The second example shows that the motor is fused at what the line wires are rated for (#14AWG is good for 15A). If something is fused already at one rating, why fuse it again you may ask. This is because the load (motor) is subject to different types of failure. If the motor short circuits, then the fusing for that motor alone will blow, leaving power for the rest of your controls (possibly an alarm light to let you know that there is a problem with your motor. If the fuse ratings are cascaded right, you should only lose one piece of equipment instead of putting a spike on all components.
  19. There are many who tend to assume that ground fault is all about total failure when in fact, many motors and transformers are in some state of ground fault. I cannot count how many times in my career as a motor repair tech that a customer brought us a running motor for preventative maintenance and it failed insulation tests due to dirt, grease, moisture or some contaminent. These motors would not be 'blown', just near failure and with a good wash and bakeout they would run for many years to come. It used to be you had a plant electrician who would megger test all the critical motors in a process and log the results. A difference in readings over time indicated the need for attention. Now in today's economy, the maintenance personnel either does not have the knowledge, tools, or more often ability to take the piece of equipment offline to perform the test. That is if there is a maintenance department at all. Having a control system designed to monitor these conditions automatically is becoming more commonplace as companies try to find ways to keep running with minimal overhead.
  20. Depending on the size of the motor and the application, detecting ground fault early can save much in maintenance costs. I am not sure what you have, but say you have a large costly motor. The mechanic on night shift has nothing to do so he overlubricates the bearings. The grease leaks out all over the windings till they are saturated. Eventually depending on the type of grease and type of wire used in the coils, the insulation can break down or leak some current to ground. If the sensor trips out first by detecting the low levels of fault, now you can simply send the motor to a repair shop to be cleaned and possibly redipped (another coat of insulation applied). This is much more cost effective than letting the fault grow till a short occurs, making a full rewind or replacement necessary. There is a manual available for these http://samplecode.rockwellautomation.com/idc/groups/literature/documents/um/193-um002_-en-p.pdf and if you read it you can see that there are many available monitoring features that help protect the motor such as phase loss, current imbalance and things like that. Some can be simply for monitoring purposes only, but being a solid state device it should protect faster than old fashioned overloads (heaters) that are based on heat and time. Remember that the heat that trips those is also being applied to the windings of your motor.
  21. Cameras

    After searching with minimal results I figure I will put it to you all. I am trying to find information on implementing a camera that will verify product selection based on color. Basically this is a mixed product and has several hues, the goal is to verify the proper colors are going into the right packages.
  22. Cameras

    There is no spec yet for a required processor type, nor has a budget been defined. The customer is looking at this project with year end increase in productivity in mind, and if we get close to the 10% increase we are shooting for, budget probably will not be too big a concern if it is reasonable. The material is a hardened concrete type product, with uneven and porous surfaces.
  23. EEPROM Loss?

    110 is fairly hot to the touch, not comfortable running equipment that hot, but if you do the conversion it is about 43C and the AB spec says it is good up to 60C....
  24. EEPROM Loss?

    how hot is hot? Do you have an IR temp reader? What kind of time period are you powering down for? AB has a list of what may corrupt the memory on these series processors. http://au.rockwellautomation.com/applications/gs/ap/gsau.nsf/pages/SLC500_Installation_CheckList
  25. Motor Plate

    You have a 50/60 hz 4 pole motor. At 60Hz it is only useable at 460v, probably due to the amount of backiron, but at 50Hz you can connect it Delta for 220-240v or Wye (star) at 380-420v. It is 3 phase, seen at the top, and the RPM factoring in slip, at 50Hz is 1455 rpm and at 60Hz is 1755 rpm. If you know how manyu leads, there are references on how to connect for Wye or Delta. Usually a six lead motor is W1 U1 and V1 to L1 L2 and L3 respectively, and tie together W2 U2 and V2 for Wye, Or if labeled 1-6, 1 2 3 to line 4-5-6 together. Let me know if you need more info, Part of our business is motor repair so we have extensive reference material.