Ken Roach

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About Ken Roach

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  1. Communication: PV +600 to SLC 5/03

    The old PanelView 550 has that "2" in the part number indicating that it has a DH485 network port only.   So it would have connected to the SLC-5/03's Channel 1 DH485 network port, either through an AIC isolator or just directly with the "AMP->RJ45" cable. If you had to stick with DH485, you could do it with a 2711P-RN3, or you could use the serial port driver version and use a converter like the 1761-NET-AIC or equivalent.   It's not great;   you can't test it on a Windows 7/10 PC because that driver ONLY works on the CE boxes. It's easier/better to switch to using DF1 Full Duplex, so that you can more easily connect a modern Windows PC to the SLC's serial port or the PanelView's serial port.   Yes, you have to unplug the PanelView to connect to the SLC-5/03, but unless you're fully geared up for DH485 with a 1747-UIC interface and some isolators, that's a reasonable compromise.
  2. SLC 5/03, 1747-KE & 1747-OA16

    By my recollection, the 1747-KE Series B modules could get their configuration from the Output data table instead of via the console port.    If there's no references to the I/O or M1/M0 files for that slot, then the module is a Series A or it's just not using that feature.   You'll have to connect to it over RS-232 to get the specific configuration of the serial port, but there's a 90% chance it's just set up to behave like a DF1 Full Duplex to DH485 bridge.    The 1747-KE does not route comms through the backplane;  the RS-232 port and the DH485 port need to be physically cabled to something.    They were often used to connect dial-up modems to a DH485 network to allow remote connectivity to an SLC-5/03 based control system.   If all the devices were wired into a DH485 network, the KE would give you access to both the SLC and the PanelView without needing a local 1747-PIC connection. The user manual for the 1746-OA16 and it says 2 mA off-state leakage, and the 1769-OA16 user manual shows the same.   I'd say those modules are equivalent. I tend to prefer to migrate simple old PanelView Standard applications manually to Red Lion, but you can migrate to PV+ using those tools as well, once you upload the program (or use a memory card to copy it out of the terminal).
  3. What kind of HMI device are you using ? How does the HMI read the flowrate ? If the HMI reads from the MicroLogix 1400 data tables, that's fine.    We can figure out where the data is being scaled incorrectly by examining the MicroLogix 1400 program and the HMI program. If the HMI is reading directly from the Promag 50, or from some other instrument, we need to know that to figure out the difference between those signals.  
  4. You have asked a variety of questions about this project for the past several months, including correspondence directly with other Forum members. If you are taking it up again, please provide details. You have repeatedly claimed that your PLC "pulse count" does not match your HMI "pulse count" but you have not explained if they use different instruments, or if the HMI shows a value from inside the PLC.   Do not start posting a new question and expect Forum users to research your past to understand the history of the system you are analyzing.
  5. Selectable Timed Interrupt (STI)

    I cannot understand what you are trying to do;  you're forcing Inputs and Outputs off as well as fussing with the STI, and you're doing it all in the Emulator instead of using real I/O.   What is your purpose with this logic ?
  6. Selectable Timed Interrupt (STI)

    Many of the hardware-related features like discrete interrupts don't work in the Emulator;  the Knowledgebase goes into some depth: But the STI is supposed to work with the Emulator. I don't understand why you are enabling and disabling the STI in the same File 2.   It's a timed function, and is going to be disabled except between the last rung and the start of the next program scan.   When did you expect it to execute ?
  7. The MicroLogix operating system only automatically executes Ladder 2. All of your other Ladder routines must be called with a Jump to Subroutine (JSR) instruction from Ladder 2, or executed by a system interrupt.
  8. 1756-hsc/b problem

    Does the control room meter display get its signal from the same flowmeter output ? When you change over a PLC to a new model, most of the I/O and signals work in a similar way.   But they aren't always exactly the same, so you need to research signals like this one. I don't think it's fair to say "it's very strange" until you have examined the whole system and program.
  9. 1756-hsc/b problem

    Thanks for the screenshots ! Those appear to show that your PLC-5 code used a data block starting at N9:84 that was 44 Words long to configure the 1771-VHSC.    The screenshots of N84 show that all the values in that data block are zero, which suggests that the VHSC was configured for all defaults, which you've assessed to mean Counter Mode, No Store, Rollover = 0, Preset = 0, and Scaler  = 0. What kind of pulse signal does your flowmeter generate ?   What's the voltage, what's the pulse rate, and how long (in ms) are the pulses ?   I'd have to look up the default filters on the 1771 and 1756 modules to see if they're similar. How do you evaluate your flow;   do you count up a number of seconds then capture the Accumulated Count, then calculate the flow ? Could the logic that triggers that calculation be different between the two systems ? Is the ControlLogix sending this flowmeter data back to the PLC-5 for you to do that calculation (I see that there's some copying of the 32-bit value into ControlLogix tags that are equivalent to N8:70-71 and N8:72-73)  ? Is the deviation of the volume flow consistently above the old measurements, or consistently below, or is it always different ?  
  10. 1734-232ASC

    You will have to do it in blocks. Most ASCII devices like label printers use a delimiter (usually Carriage Return and/or Line Feed) instead of a timeout.   You will have to split up your string into multiple sections and use a sequencer to send them one at a time, with the delimiter on the last one.
  11. I did a lot of searching for a hardware interface or method to talk via Ethernet to a Fanuc 30i family controller and did not find one. I used the FOCAS OPC Server product directly from Fanuc Support North America.   Relatively inexpensive, but the jury is still out on the reliability;   I had some trouble understanding the update mechanism and some "stale data" issues.
  12. AB Micrologix atomic memory read

    Thanks for the clarifications and follow-up ! A MicroLogix or SLC-500 does not service communications during the program execution (with the exception of explicit SVC instruction interrupts), so there is no risk of having your loop or COP instruction be in between the instructions that assemble your data into the Integer data table when the data is read by the external program. There is definitely that risk in ControlLogix. CPW was added to the instruction set for the MicroLogix 1500, and then moved forward into the 1100 and 1400 controllers.    It was built to accept operands of differing data types, in part because of the addition of Modbus RTU to those controllers and the need to pack 32-bit Floating Point data into Modbus Holding Registers.   As you have found, it's also useful for manipulation of Long Integer data tables.    
  13. AB Micrologix atomic memory read

    The MicroLogix and SLC-500 operating systems are functionally single-threaded, so they service communication requests based on the data table values in between execution cycles of the control program.    There's no way that I am aware of for an element of a data table to change during the reading of an array of elements, even if it is changed by a Routine that is executed by a Periodic or Event interrupt. Strictly speaking the data tables are "atomic" down to the Element level;   if you read N20:0 through N20:3, that's four elements, not one. This is different in the ControlLogix family, which has a task scheduler and communications services in the background.   You can encounter (and I have) circumstances where data in an array changed during a communication operation.  I use the Copy Synchronous (CPS) instruction in ControlLogix to lock the source and destination tags when I need to assure integrity of an array of data.
  14. You can "fake out" the older controller by entering the L33ER as though it was an old 1769-L35E.    There is no version dependency that I am aware of that prevents any ControlLogix or CompactLogix from exchanging Produced/Consumed Tags with any other ControlLogix or CompactLogix that supports the same networks.  
  15. The "remote" 1756-ENxT, the chassis that contains it, and the "Producing" 1756-L73 controller must all be in the I/O tree. The 1756-L73 is definitely supported by Studio 5000 v30.