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About dierkens

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  1. dierkens

    Modbus TCP...know forwarded data

    You should use something like a MODSCAN to test the reading/writing of registers/coils on both ends. Although you indicate that your PLC works as a slave, you must mean that they are sending the MODBUS register information to your PLC. You can use WIRESHARK to get down to the packet level of information; but that level of detail typically isn't needed. Can you ping the MASTER device? Can the SLAVE ping you? Have you checked the OFFSET to make sure that both devices are using the same array start [Zero (0) based versus One (1) based register assignments]. Start with something easy like coils or a lower register. Just use some basic MODBUS troubleshooting techniques.
  2. dierkens

    Modbus TCP...know forwarded data

    Not sure why you want to ( error checking, byte manipulation, etc)? Read this and see if it answers any of your questions. https://www.rtaautomation.com/technologies/modbus-tcpip/
  3. dierkens

    I/O Specification Equivalents

    They're a mix of 0-5v; 0-10v; with the majority of them 4-20mA. 8 of the inputs are from the same source (a DCS); there's 6 separate Voltage Inputs and 17 separate mA inputs. I've got two (2) choices; either purchase some isolation modules (at a cost of about $75/input) or use another companies I/O products that are isolated. Are there any other non-Unitronics modules that you'd recommend?
  4. dierkens

    I/O Specification Equivalents

    Yes, I've looked at the specifications for what's posted. I just want to make sure I'm not missing anything.
  5. I've got a project where we're trying to replace a customers existing Emissions Monitor data logger. I'm trying to match the specifications of their current products to the equivalent Unitstream I/O products. I've looked at the specification sheets for all of the I/O module and I'm not seeing a direct correlations between some of them. What's the best way to post up the specs of the existing I/O to see if you guys can help me match it. Here's an example of the Current Input Cards of the existing controller. I tried to post the specs here in the post itself but I couldn't lay it out nicely; so there attached. Any help is really appreciated. Existing Controller IO Card Specifications.pdf
  6. This is exactly what I was going to ask. Your update rate will always be limited by the speed of your serial port and how much data you're getting from the devices. Crank up that baud rate on both ends and see what happens.
  7. dierkens

    How to take a screenshot from Ladder?

    Sounds like a good idea; but if you're going to have a screen filled with the data you could create a data table that will have all of your diagnostic info and then write this to a file on a secure digital periodically. A log file of sorts.
  8. dierkens


    You can save the output to a csv file onto the SD Card. How often do you need updates?
  9. I was thinking the same thing. I sure hope it was a typo... I can't believe anyone would set up a program that interpolated them with that range. One thing he may want to try is get Modscan or equivalent and test it real quick.
  10. Make/Model of the device?
  11. Yes; put it behind a firewall and use a VPN to get access to the network.