baldyspate

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About baldyspate

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  1. voodoo functions

    Thanks for the replies. You've answered my question. I can see that the math blocks in question may well effect balues elsewhere in the program, as the values are eventually moved to integer files elsewhere. Sorry, for the incovenience with giving enough info at the beginning but I'm not able to connect to the net with the laptop which accesses the palletizer plc. Thanks again.
  2. voodoo functions

    Hi: I'm trying to sort out, thin down, and document an uploaded palletizer program modified, modified... from an slc5/04. I"ve already found and deleted one "left behind" ladder in the files, and was about to weed out another when I thought that I ought to double check an assumption. In the file in question there are ADD,MUL,and MOV's involving the presets and accumulators, of counters and a timer which aren't defined anywhere else in the program. I mean not as a CTU or CTD block at the end of a conditional rung. They are just referenced as sources and destinations in the math blocks. I was about to nuke these when I thought that I'd better find out if the memory locals or some other feature of these might be assigned permanently and usable or some other (by me) unthought of way that this is possible. Appreciate your time
  3. I don't understand!

    Oops... There was a jump statement and it was the culprit. The physcal input which would have made the (JMP) rung false had been removed along with whatever equipment it used to be wired to and undocumented wiring mods to go with it. I aggravated my troubleshooting problem by somehow latching the input true and leaving it that way for a while. I'm not real experienced with PLCs but even I should have noticed it. Thanx, it was fun and good experience, with RSLogix while correcting the problem.
  4. I don't understand!

    You made me rethink. Thanx both Psycho and Ron It's a rare thing, but I may be wrong.... about the previous rungs. There may be a mov or some such I can't check for a while but I'll bet one of you are right. either somethings interfereing or changing the initial value in said output file bit. thanx... If you're still interested I'll fill in some blanks tomorrow. in this toopic
  5. I don't understand!

    Sorry, I don't have access to the file and the net at the same time. Paranoid people. This is on the fourth rung of the first file in the program. There are 11 files, but not jups or calls, etc, ahead. There are only writes to bits and a timer ahead of this rung. It's the second input and first output of the program. I only discovered it because I was wondering why there were two wires to the ouput when there should have been only one. Someone had moved the input wire (from two p/p switches in series and supplied from the same power terminal as the output commons ) to the output terminal, maybe years ago, to apparently get around the problem. Leaving O:5/8 attached, natch. Seems a little....dangerous. I love this site...wish I stopped in more.
  6. I don't understand!

    Hi Fellas: This isn't critical and it's not going to be fixed or replaced. I'm curious though... An SLC500/? w/120V inputs and triac outs: The program on one rung uses an input and an output as a simple relay. -------| |----------------------------------------------------( )----- I:2/0 O:5/8 In this case, when a real input is applied the card shows such on the led display, but there is no output. Using a laptop I toggled the input and it showed active in rslogix while the output did not.(in rslogix or for real) When I toggled the output with rs... it showed active on the screen, the led, and energized the motor starter it is connected to. I understand a proc reads the inputs to a file, processes the values to an output file, and then writes the outputs to the ouput card. I'm having trouble picturing how the above combination of results could happen. Thanx for any answers or ideas.
  7. Tough wireless

    Hi: It's been a while and this forum was very helpful then and tho this ain't about PLCs... I'm looking to clean up a very messy situation in an exposed (to product, weather and physical impact) location with an eye towards more automation in the future. It involves hoists, booms, SO cords, RTD or TC wire, and dangling pendants. I'm thinking that wireless RTD transmitters can help with part of the job. The ideal, at least one with some reality attached, would be a Xformer / pwr supply which would pick the 480 from the motor leads right at the motor and supply 120 volts to a wireless xmtr that is already in the supply pipeline. I'm looking for advice in finding as small an industrial quality transformer/pwr supply as possible ( < 10 VA?) and also I'm concerned about the electrical "safety" of the transmitter. I'm not sure about transients, inductive spikes, etc. in such a setup. It will include people who will probably disconnect running 7.5 hp 480V motors at the motor, against instruction, though there will be disconnect rated plug/recepts there to protect them. The the resulting "equipment" would be protected from physical impacts up to and possibly including sledge hammer attack, but will be within a couple of inches of the motor and limited to a few cubic inches in volume. Any advice or directons to information would be greatly appreciated. Baldy
  8. Timers

    Thankyou Tech... I hoped that it would be as simple.
  9. Timers

    Hi: I'm an industrial mech/elect. and (very)limited plc programmer working in the food industry. I'm gradually making improvements to a process that I inherited. I'm looking to see if I can, with timers and math in a Micrologix measure the effect a part of a process has on a subsequent part, and having the PLC do some relatively simple math (not PID, since this needs to be understandable in principal and all practicallity to a high turnover group) and change the timer settings of the first part while running. If this is overly novice for this forum I apologize. Would that I had the time to research. Thanks for YOUR time.
  10. Hi: Please excuse the length of this. Where to start? That question kind of somes it up. I'm looking to acquire some kind of basic knowledge of the communication protocols that I find in reference to AB plcs. I'm not so much looking to become adept at it as be able to understand what I read in the manuals. Those manuals that I've found so far assume knowledge and vocabulary that I haven't acquired yet. I'm boning up on IP and there are enough links to info on that to keep me happy, but when I'm trying to sort out DF1, Modbus, DeviceNet, etc., I find myself a little too ignorant to measure my own ignorance or where to find what I want to know about a specific technical item. Are there any "The Basics of..." re: Allen-Bradley device communictions out there? Any suggestions on how a self learner would proceed? I'm working through the automated processes in our plant and gradually making changes as I and/or the operators/supervisors see fit to reduce the time to product volume ratio. (though not truly increase production). I've learned bunches about programming plcs and applying that to the floor in the last few months, but am starting to see where operator interfaces and networking the plcs would help in applying daily or hourly front office decisions to the floor with much less disruption. The plant is networked for admin purposes and seems to have far more capacity than is being utilised... I'll just stop there. Baldy
  11. Coding Efficiency?

    Yep. I'm new to PLC programming and somewhat to industrial maintenance, but have been doing basically this type of work for a long time. (haven't worked on the Shuttle yet but...) Happy users are more important than many, who should know, seem to. For a long time here it was, "...take what we give you..." That's changing but with some pain, for some. The mods that I've done so far are the result of spending some time with operators. In one case almost just translating and sticking what had been a fellas wishful thinking into a ladder. He'd been wanting it for that long. What's "driving me mad" at this point is probably stuff that you solve without hardly a thought, but I'm improving (I think), and t'were it easy t'would would also soon be boring.
  12. Coding Efficiency?

    And yet again...Thanks. I've picked up a lot here (measured against what I know). There're badly bruised egos lying all over the plant floor over the two lines that I'm attempting to work on. The good news is that MY boss is on my side. And he is coming around on the rewrite after a couple aof successful changes which the operators love. The filler line is far and away going to be the easiest. It produces as much product as can be shipped from here and the issues are economy and spills. I'm certain that I can reduce the number of spills and the amount of spills when they happen without too much trouble. The operators are good hands but are working with a system that has no provisions for less than perfect sequences of events. There are no lights, gauges, bells, or whistles for the operator to glance at before he hits the E-stop, so often he has no clues to give the maintenance people when they show up, while there's plenty of data fed to the plc which can be used to evaluate events and call on fault routines. I was a pretty good hand with my trusty C-64 and it's poking and peeking around the interpreter back when it was Rex but haven't done any programming between then and very recently, after a short course on ladder logic. After I sharpen my teeth (those left) on the filler I'll go after the real grizzly and will probably be.... right ...back... here..................
  13. Coding Efficiency?

    I'm surprised that I'm actually following this. If your still there... I'm making changes to a filler program that I inherited from another, apparent, amateur. I ( find myself trying to paraphrase, "the blind following the blind" but ain't a poet neither). I find timer resets that would seem to reset every scan for up to a couple of seconds, and retentive timers in places that would seem better suited to nonrentative timers and need resetting. I'd like to make this finicky process as "idiot proof" for the very busy operators as possible, adding lots of logic. It's only about 50 rungs long, with up to 9 arguments per (avg:~4), and with no JMPs, JSRs, or MCRs. It needs at points to be acurate to around .01 secs. I'd like for my own practice to make it efficient, but this is a business and I am wondering if modifications (can't start from scratch...nervous boss) tripling or quadrupling the length would benefit from time saving mods. Micrologix 1000, no spare outputs, one input left....... thanks
  14. Coding Efficiency?

    Thanks. Very informative and will be very helpful.
  15. Coding Efficiency?

    Hi: I'm a newbie to writing. Self educated or semi ignorant... I've read or heard that (AB PLCs at least) will only evaluate a rung to the first false statement, update the rungs output, and then go to the next rung. Is this true? If so, it could make a lot of difference and be good practice to put the most often false arguments at the beginning of a rung. Also true??? thanks.