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  1. How can you log data flow totals in a AB 1100

    Mickey's going old school!  Used to be the way we had to handle floats for some processors.  Glad those days are past, but that is a valid way to use integers.  The problem that I think you will have with the micrologix is a 256 max data table.  I think you can only have 256 elements in each data table.  Maybe mine is old.  If this is a problem then you will need to split your 365 elements into 2 different tables.  I would suggest that you could use indirect addressing to move your values directly into floating point registers.  When your index is greater than 255 then enable a different move that points to a different table.  Something of the format:  F8:[N7:0]  where N7:0 is the index of the element in your F8 file.
  2. Studio 5000 Logix Designer

    No problem.  Hope it helps.  I cut my teeth on the PLC5 and never had the opportunity to work with the PLC2, but a cross reference is a cross reference.  One of the things that has changed since that time is the mobility of the computers.  While I never worked with one, I had plenty of sites in my early years that had one and usually they had a large terminal right at the PLC for modifications.  If you wanted to look at the program anywhere else, you used the printout.  Now with the more mobile computers, it makes more sense just to learn to work within the software instead of prints.  The searching capabilities and speed of the newer computers all combine to make this much more efficient.  There is a mental change that you have to make to take this step.  I would suggest moving over to the computer for searches and other such operations.  It is a big mental step when you first go from the prints to the software but well worth struggling through.  The newbies never dealt with this issue as they always have used the software. 
  3. 1747-NI8 Open Circuit

    I'm having a hard time with the open circuit with slightly under 4ma.  I reread his post and he does specifically indicate that he is receiving an open circuit condition.  That throws out any underrange condition that I veered off course on.  Maybe the power supply is wigging out (technical term) or maybe the card has problems.  I would not assume a processor fault just because the machine goes down.  The open circuit condition makes the input value fail high or low and that would very likely trip a limit in the program to make the machine stop.  If I remember right, the manual says that the open circuit function is only operational in the 4-20ma mode.  That would be another reason to try the 0-20ma just to get away from that function.  Keep in mind that you may have to do some rescaling.  I would also add some logic to check if the input is dropping out (maybe less that 2ma).  Just because you cant see it while monitoring doesnt mean that the PLC doesnt see a quick dropout that is more dramatic than 3.96ma.  A rung with a LES and a latched bit would be a simple way to check if something is happening that you are not seeing from the programming software. 
  4. 1747-NI8 Open Circuit

    I cant find in the manual where the open circuit function is looking for the input to just go below 4 ma.  That doesnt make sense.  What would the underrange bit be set for?  I think the open circuit function is just that.  It looks for a load and if it doesnt see one then it alarms.  If it was just looking for a below 4ma condition then a quick work around would be to setup the inputs as 0-20ma, but I've used this card in the past and not had this issue.  It's not unusual for a transmitter to send a value of 3.95 or such at the low end of its range.  Generally the 4-20 inputs will read slightly below 4ma and slightly above 20ma.  I would still check the logic to make sure its not programmed around an underrange bit.  If it really proves to be the open circuit function causing the problem then you may have a damaged card or field device.
  5. Studio 5000 Logix Designer

    I never really print programs any more.  It's generally best to get used to just getting around in the software and using the cross reference function in there.  A printout can be very big.  I thought I would just test with one of my current programs and I gave up after it was showing 1000+ pages and wasnt even a tenth of the way through.  That said, the answer to your question is yes.  The cross reference will look very different as you have tasks/routines and programs as well as different programming languages other than ladder.  In the print setup you can go to the tags section and select to print the cross reference.  It will look something like this for each tag: CoatPumpB.ManMode 0 BOOL Coating Pump B Drive Interface Mode Select 0=Automatic 1=Manual CoatPumpB.ManMode - VatRoom/CoatingPumpB - *5(OTU), 10(XIO), 6(XIO), 8(XIO) First line is the tagname, value and type.  Second line is the description and the third is the cross reference.  VatRoom is a program and CoatingPumpB is a routine.  You can see the tag is used in an OTU on rung 5 and so on.
  6. 1747-NI8 Open Circuit

    I wouldnt think almost 4ma would present as an open circuit.  It may have an underrange bit that could be being used.
  7. HMI/SCADA selection for HVAC energy management

    This is just a copy of my reply to your PM: Your application sounds more commercial than industrial and is not really part of my experience. I can offer some advice. Every SCADA package demos well.  It's not until you actually start working with it that the deficiencies come out.  Find users of your top picks and quiz them.  Also see if there is demo software available and try it out.
  8. What is your favorite and least favorite HMI software?

    Well I believe they think they are.  They even have a manual that covers part 3 of the standard.  Unfortunately my understanding is that the standard is so loosely defined that compliance doesn't actually mean much.  Not like you can take a siemens program and load it on an ab.

    When you setup your generic Ethernet module, make sure you select the correct data type.  This has snagged me more than once (sorry to admit).  It's very easy to forget and use the defaults and just fill out the number of input/output and config words.  I believe it will show a valid connection on many devices, but the data transfer will be messed up.
  10. Easy to use 3rd party HMI to use with ControlLogix L82

    I am very partial to the Inductive Automation Ignition platform.  Am using it with contrologix, plc5, slc etc right now.  I would suggest conerting your connection to your Modbus/rtu network to an Ethernet based interface.  Ignition is a server/client based system and ethernet is much easier to connect to.  Moxa sells some great little gateways to allow connections to legacy networks like that.  You mention desktop, but if you are interested in a local HMI then I would suggest RedLion.  Also connects well to the logix.
  11. What is your favorite and least favorite HMI software?

    I'm not sure if that was a rhetorical question or not.  Pain the the neck usually causes downtime. Pretty easy to figure the return on downtime cost vs equipment/development cost.  I'm not really a fan of anything Mitsu - PLC's, displays, cars, etc.  Me and Mitsu just dont seem to get along.  The AB software is really expensive; however, it works.  It has a lot of features and they keep improving it.  I'll pay for quality.  Also there is a time component.  I can program twice as fast - maybe even a greater multiplier - in the RSLogx5000 platform versus most others.  Partially due to my experience with that compared to others, but also due to the structure and ease of programming in that package.  The hardware is also pretty solid.  Install and forget.  Let the spares gather dust.  Finally there is a sanity factor. What's left of my sanity after years in this business is worth paying a little more to me.  Most of the Japanese processors seem to target eliminating my remaining grasp on reality. 
  12. How do you test PLC logic?

    I run the test versus a test document for functionality.  Retesting is a case by case basis.  Most of my logic is very modular so just rechecking the module will ensure good results.  I had full chemical plants come up and run perfectly after an I/O field checkout. Just don't see the need for a separate piece of software to do what is already manageable in the controller itself.  In addition it cuts down on training as engineers already understand how to program the Logix.  These other packages will need training and time to come up to speed on the simulation software configuration.  Simple is always better in my book.
  13. Load different programs on power up with compact logix

    This really does sound more like a recipe application rather than a new program situation.  Many places have a hard time keeping up with one application for a PLC.  I think you would find it to be an organizational nightmare to have several programs for a single machine.  Also keep in mind any changes to the machine would require changing all of those programs.  I think you want to avoid the multiple program path at all costs.
  14. How do you test PLC logic?

    This is the way I have always done simulation.  Maybe every project I have done would be considered simple to people here, but I have simulated full chemical plants fairly easily with this method. Every program has logic that automatically puts all I/O into an inhibit mode when simulation is selected.  Simple items like valves, motors and drives have blocks that handle I/O transfer.  Simulation of that module is part of that block.  Batching, temperature control, flow, pressure, etc. are not really hard to simulate in a basic manner.  Generally the simulation is to wring out the program so I never had to actually model the process.  My purpose was not really to assist the chemical engineers in figuring out their process as it was to make sure my system could control the process properly when it was installed.  In addition to simulation, this allowed me to train the operators on the system before the actual startup.  I really never have run across a system that I could not effectively simulate this way.  Someone did mention servos.  That is an area I never had to simulate, but over the last 30 years I have put together some pretty complex systems and never found a third party system that added value to what I was already doing.  Most of my recent systems were Logix systems and they are particularly suited for this type of simulation.
  15. InTouch Comms

    If my memory serves me right (can be questionable), I think the only way you can connect to any of the emulate programs is via RSLinx.  You would need to setup an OPC connection from RSLinx to Wonderware.  You will need the version of RSLinx that is capable of this - not the Lite version.