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  1. NWBeaver

    Why not Ethernet vs. RS-485?

    Another thing to consider is the field devices. How many of them actually have an Ethernet port?
  2. NWBeaver

    Cables screen & drain wires. Collective or individual screen?

    Like roydm says, if you are using separate pairs for 4-20 mA loops, I would use the individually shielded pairs. The overall shield cable works for something like an encoder, which uses more than one pair for a single device.
  3. NWBeaver

    F & FW RSLogix

    If you open the input file and click on the Help button, there should be some explainations of the usage characters. . Not being used in the project file X Being used in the project file W Being used as a word address in the file F Being used as a file address in the project WF Being used as a...
  4. NWBeaver

    1746-HSCE Encoder, Measuring Long Lengths?

    From your description, I think I would consider using a PID loop for this. Scale the sheet sag and floor positions both to mm. The PV is the (floor position - sheet sag) in mm. SP is in mm. The loop CV is the drive speed command. Using reverse acting, E=SP-PV The loop will try to increase the CV...
  5. NWBeaver

    1746-HSCE Encoder, Measuring Long Lengths?

    Depending on the resolution your application requires, you might consider changing the encoder or the encoder coupling. If you can tolerate a lower resolution, either replace the encoder with one that has a few less counts per revolution, or change the encoder coupling to reduce the revolution...
  6. NWBeaver

    'First-In Latch'

    Sequence Of Event recording is certainly a good way to go, especially if the events occur faster than the PLC scan time. I believe that Jim is using a SLC504 though, so a 1756 I/O module might not work too well. Perhaps someone makes an SER module for 1746 I/O? Another idea along that line of...
  7. NWBeaver

    'First-In Latch'

    You could probably do this by simply testing the value of the input register, say I:1.0 for example. If all the bits were normally off, then if I:1.0 > 0, you would save the value of I:1.0 to a register such as N7:1, and set a bit to inhibit the logic from executing again until you had looked at...
  8. NWBeaver

    Installation of Magnetic Flow Meter

    Mag flow meters can usually be mounted anywhere from horizontal to vertical. You do always need to install them in a straight section of pipe, at least about 5 pipe diameters downstream from any elbows or valves. If the pipe does not typically run full, you can pipe it in, with a U or V shaped...
  9. NWBeaver

    CompactLogix Time Date Control

    You might take a look at the GSV instruction and the WallClockTime object. You could read the DateTime attribute periodically to see what the time of day is, and trigger an event at certain times.
  10. NWBeaver

    Help for critical issues

    One other comment on this subject, is that this type of problem can appear to be random due to the hold up capability of the PLCs' DC power supply. If the power outage event is brief, it may take the machine down, but the PLC may ride through because the DC power does not drop out instantly...
  11. NWBeaver

    Help for critical issues

    The transfer switch will typically have circuitry that can compare the phase angles of the generator and the grid, and attempts to reconnect the load to the grid at the precise instant that the phase angles are the same. or "in phase" with each other. This is important in the case of a closed...
  12. NWBeaver

    Help for critical issues

    If I understand correctly, you are saying that the problem occurs when switching from the generator back to the utility grid? If so, I would have a look at the transfer switch. If it is a closed transition switch, the generator and grid need to be in phase with each other, before the switch...
  13. NWBeaver

    Anyone know how to take accumulator values and put them into excel

    Collecting PLC data typically requires two applications, an OPC server, and a client. The OPC server application is specific to the PLC that you are attempting to connect to. It connects to the PLC and reads the data, which is then available to an OPC compliant application. A spreadsheet such...
  14. NWBeaver

    Omron PLC to B&B serial/fiber converter

    The SYSMAC BUS used by the G72C-ID16 units is specified as being RS-485, Half-duplex, 187.5 kbps Matching the baud rate could be an issue, along with other things like polarity and termination. Omron also makes a Link Adapter, AL007-P, which is used with wired remote I/O to convert RS-485 to...
  15. NWBeaver

    Remote IO with Fiber Connection

    If you really want to connect the I/O modules peer-to-peer, (with no PLC in between), then the Acromag modules you linked to would work just fine, you simply need media convertors at either end of the fiber link. The media conversion could be either a single FX-TX convertor, or a switch with...
  16. NWBeaver

    RSLogics 5000 plc V13.03.00 forces

    Just a guess, but from looking at the picture you provided, I noticed that you appear to be using some sort of redundancy. I don't know too much about it, but I would look to see if either the primary or secondary chassis is locked, as that will disable forces.
  17. NWBeaver

    PLC/HMI combo to use

    Not difficult at all, the SLC PID instruction uses "N" registers. You would just need to create a Control Block of addresses such as N10:0 thru N10:22, for example. In this example, the PanelView would then access N10:2 to read the Setpoint value. The SLC instruction set manual maps out all the...
  18. NWBeaver

    PLC/HMI combo to use

    Is this intended to be a stand alone system, or is it part of a larger system. By wanting to create and download recipes it sounds like a PC of some sort would be involved, to store the recipes. A PLC such as the SLC 5/03 for example, has a built in software PID loop instruction, and just...
  19. NWBeaver

    Microsoft Excel use with a PLC

    Excel by itself can't send instructions to the PLC, you will need another piece of software to handle the communications between the two. Depending on what type of PLC you have, and how you want to communicate with it, you should be able to find the right application. There are a number of...
  20. NWBeaver

    Andon lights

    I meant to say that could have all the lights controlled by one PLC, not must. What type of central location monitoring are you considering?

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