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  1. Report Button

    Seriously it is getting bad.  This could be the death of a forum and I hate to see it.  Are links on the forum setup as no follow?  This should cut down on spammers as there is no search engine benefit.    
  2. Report Button

    I feel your pain!  I know from my website that it is a constant battle.  You already have the captcha for new account protection.  I would suggest contacting the creator of the forum software to see if they have any solutions available.  This kind of persistent hacking could really damage the forum and you guys have a great thing going here. 
  3. Difference between l33erm and 306erm.

    Funny that this just came back alive today.  I just checked out my 306ER installation today.  I specifically need a separate I/O subnet and SCADA subnet.  I have flex I/O and an E&H transmitter on one port and SCADA and messaging to an old PLC5 on the other port.  Used to have to go up to the Logix to get multiple networks like this so it's pretty cool.  The money for the PLC5 upgrade is a ways off so I'm using the compact to bring in devices like the E&H transmitter over the network.  This will allow us to move forward on our near term sfield device selections that will integrate nicely with a new logix in the future. 
  4. Difference between l33erm and 306erm.

    The difference that I was looking for was that the 306 has dual ethernet ports that can be individually configured.  This way I can separate my I/O network from my SCADA or control interface network.
  5. ML1100 And Analogue Expansion Module

    Did you set the dip switches for voltage?  Default is current for the Analog inputs. page 12 in this manual.
  6. My Model Train Project

    LOL spoken like a true Ham op!
  7. My Model Train Project

    Yeah I actually use the register method more than the counter method for keeping track of steps.  You see that Joe has each step 10 apart, ie,  10, 20, 30, etc.  Similar to the way we used to have to program in BASIC when you had to put line numbers.  That way you could insert lines without having to renumber your whole program.  The same applies in the code he has.  He can easily insert another step, say 15, without screwing up his whole numbering scheme.
  8. My Model Train Project

    Sounds like you are heading in the right direction.  As for sequencers, I am not usually a fan.  As I am generally programming in ladder somewhat because it's easier for the techs to understand, the sequencer flies against this logic.  I prefer to use something like a counter to step through sequence steps and operate logic based on what step I'm in.  This works particularly well with each of my equipment pieces being a looked at as a module.  So i might activate a bit that is defined as step 1 when my counter accumulator is 1.  I will use that bit in my valve, pump or other equipment logic to activate required equipment when the equipment is running in automatic.  It's very easy to see what happens in that step 1 with a cross reference of the address.  In addition when someone is looking at a valve operation (for example), they can immediately see that it is active in step 1.  Finally it is very easy to see what cycles the system to the next step.  I think it's more clear than a sequencer.  This is all programming preference.  There are times when I have used the sequencer when the end user preferred it.  PLC programming is very much programming to your audience. Program in a way that works for the expected user. 
  9. My Model Train Project

    Well I have to say that you get the planning stage much better than many coming to the PLC programming field.  I see experienced programmers that see no need for any planning document or specification.  I would assume that comes from your previous programming experience.  You have put together a basic plan for program operation and detailed your I/O.  In a real world project a detailed functional specification is recommended.  It takes time and effort and is not really completely necessary in full detail to successfully program, but it is necessary to successfully define to a client or user of a system how you as the programmer and designer of the system see the system working.  Many wrong directions can be figured out early with a good document.  Well.... if someone reads it - but that's a different discussion.  I put a video on youtube a couple years ago on this.  Wasn't real popular as people want to program not plan.  Here is a link: You should be able to find lots of information by googling seal-in circuit; however, we have an old article on ladder logic that shows one about half way into the article: Essentially you "seal" around the start pushbutton to maintain the output.  Our article show the seal using a contact off of the output.  Generally with a motor seal in you use the AUX input from the motor starter as your seal.  I always use both the output and the AUX to seal in my motor circuits due to an experience with a faulty PLC5 I/O card that caused my inputs to cycle on and off for no reason.  Nothing like hearing every motor starter in the room cycling on and off together to make an impression.  As for how to start attacking your program I generally look at it like this.  Each motor/valve or other defined equipment item is viewed as a module.  Define how each operates independent of anything else. Start/stop, alarming, auto/man, etc. Define sequences that run.   Tie the sequences into the motors/valves and other equipment modules. Keep in mind with a controller like the micrologix, slc or even PLC5, AB makes it really easy to organize your data similar to how you organize your program files.  You can create bit files or integer files (and others of course) for specific purposes and have organized data as well as program files.  My general rule of thumb is not to use the generic default data files for anything other than extraneous data that just doesn't fit with anything else.  I always create data files to fit my program needs.  How you organize it is up to you.  Just do so! The micrologix 1100 and 1400 are both great little processors.  They both have ethernet ports that can be used for programming and the 1100 can still be programmed with the Micro Starter Lite.  Also both allow online programming which is an essential tool in real world programming.  We dont take a system down to make small changes to the program in production systems.  Might as well practice that way also. Hope this all helps.  Have fun!  
  10. Traffic Intersection with 3 second inductive sensor

    Kinda on the verge of hijacking the thread, but I guess it is pertinent poop for someone learning programming.  Took a quick look through your program and do have a couple immediate things that pop out:  I never use conditional JSR rungs or at least I cant remember a time that I found one helpful.  They are generally a way to get into trouble as all outputs stay in their last condition when you stop scanning the subroutine.  The mantra in PLC programming is "keep it simple."   This is a program just for you, but generally we are programming for the multitude of people that will follow us into the program after we are done.  That is very unique in PLC programming.  Generally in a plant environment the level of proficiency is fairly basic.  Also at 3am in the morning when a line is down, brain functionality is fairly basic.  Imagine the fun of seeing an output on in the program with all of the logic before that output false just because the program file is not being scanned at that time.  Minds have been blown with less.  In my experience, nothing good ever comes from a conditional subroutine.  If you want an output off then put a contact in the rung to make sure it is off.  Then the logic is clear and understandable to just about anyone.  I suspect that is why you have to reset your outputs with the masked move statement.  Another gotcha waiting to happen. I never use (or extremely rarely) the JMP instruction.  That is a fairly common statement for all high level languages.  Basic has its goto and just about every language has a statement to jump to a location in the program.  Most instructors I have learned from will explain the statement and its purpose and then tell you not to use it.  Those types of statements get you into trouble and are difficult to follow in most programming circumstances.  There is generally another way to do the same thing.  Same goes for MCP.  That has some value possibly in temporarily taking sections of code out of service for testing or maintenance.  As permanent fixtures they just cause confusion when people are troubleshooting. Rather than latches use seal in circuits.  Latches generally cause problems.  They are necessary if you need to maintain output status through a power failure.  OTE's are reset when the system comes up.  Same with the resets on your timers.  TON's reset automatically when the logic before them goes off.  Resets can be eliminated and everything that controls that timer's function then is on the rung with the timer.  Thats much easier to understand when looking at the rung functionality.  Side note: RTO's do have to be reset and are useful if the timer value has to be maintained such as for a total run time of a system that is starting and stopping. Even with the subroutines you have, I would move everything from file 2 except for JSR's to a subroutine.  Leave file 2 just for JSR or insignificant overhead logic such as blink timers or such.  That will make the logic much easier to go through. Looks like a fun project! 
  11. "Display Print " button from Studio ME

    I have never used a display print function in Studio but I have had to get screen shots before.  If you have Studio, then you can run in test mode on the PC and just take a screen shot of that. 
  12. Annoying problem in Logix5000

    Yep.  Its located under the Tools menu option.  Not sure if you have to choose to install it with a separate checkbox during the 5000 install.  It's just always been available on my installs.
  13. Traffic Intersection with 3 second inductive sensor

    Mike's logic is a good example of the comparison method I mentioned.  It is also offers a chance to talk about what I meant by using subroutines to organize logic.  I encourage my students to get in the habit of using subroutines for organization even for small programs like this to practice and to get in the habit for larger programs.  I would suggest that very little logic should be located in program file 2 of a SLC, micrologix or PLC5 even.  Only JSR's to program modules if possible.  In this program, you could put all the setup information in a program file and the actual control logic in a different program file.  Not a big deal in this size of a program, but I think you can see the benefit in a system where you have lots of sub systems.  Once again - PLC programming is different than other languages.  Users will be in a PLC trying to troubleshoot at 3AM with only half their brain actually awake.  The easier it is to get to the information they need the faster they system problem is fixed. 
  14. Traffic Intersection with 3 second inductive sensor

    PLC logic has a little different mindset than other programming languages.  So no to the subroutine for this.  I actually find that subroutines in a PLC are more used for program organization than anything else.  Take that in mind and try to come up with an alternative solution BEFORE READING MINE as the struggle to figure out the solution is one of the most important things to go through in learning to program anything.  That said...  I assume from your text that this is an either or thing not 3 seconds for each 3 cars the sensor sees.  The solution is actually pretty simple.  You have a register that stores the normal time and one that stores the extended time.  You then modify the timer preset with the stored values.  It looks like this is total cycle time through all 3 lights.  I would expect you would extend the green for the side with extra cars but not the red or yellow and obviously.  if you extend the green on one side you are extending the red on the other side.  If you use 3 timers the method I would use would be to copy the extended time into the green timer preset one direction and red timer preset in the other.  An either or.  Either you are copying the default time into those timers or the extended time into the preset for those timers.  Of course you could do it all with one timer and just use comparison instructions to turn your lights on at certain accumulator values.  You would still need to extend the preset time for your timer in that case also. 
  15. Annoying problem in Logix5000

    The applying changes notification does not refer to accepting changes on rungs that you may or may not have made.  It refers to the software updating locally to match what is on the processor you are connecting to.  I'm not sure what the dividing line is between having to upload to grab changes and it allowing it to apply changes, but it has nothing to do with rung edits you may or may not have made.