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  1. Not sure it will work like that as I believe the MODBUS ID has to be set for each one individually.
  2. Make sure all of the Windows updates are done. If they are then roll it back and confirm this it’s still happening.
  3. I take it you have two images, one for state 0 and another for state 1, correct? Swap the logic and see if the image comes up correctly. Then swap the images and see if it works. That's where I'd start.
  4. Is it possible to have MODBUS TCP (Ethernet) via the CPU Ethernet? I have two separate networks I'm using. My PLC needs to get data from a DCS via MODBUS on a 172.17.100.xxx network and a computer needs to get the MODBUS data from the Unitronics PLC via a 172.16.100.xxx network. Can I do this or do I need to find another solution?
  5. Take a look at the ping command. https://unitronicsplc.com/Download/SoftwareHelp/VisiLogic_Knowledgebase/Ladder/Functions/Communications-Ladder_Functions/Ethernet/Ping.htm
  6. Fairly straightforward networking setup. By mobile network; you don't mean that you'll rely on the internet do you? If you do you're going to have to navigate a lot of security issues which I'd recommend using a VPN for. If you've got wireless and they are line of sight setup then you can setup a Point-to-Point network. You don't mention a budget nor distances between points. This is all information you'll need to determine before you pick a solution. Cisco has a decent setup but is costly. https://www.cisco.com/c/en/us/products/wireless/outdoor-wireless/index.html Hirschmann has some good products http://www.hirschmann.com/en/Hirschmann_Produkte/Industrial_Ethernet/BAT-Family/index.phtml Phoenix has some good products as well. https://www.phoenixcontact.com/online/portal/us?1dmy&urile=wcm:path:/usen/web/main/products/subcategory_pages/Industrial_WLAN_P-08-11-02-02/69d1b9c0-6359-4eeb-8fba-39e2a21dcf81 Take a look at some of this stuff. I've used these in 2 instances with success. https://www.advanticsys.com/shop/wireless-modbus-bridges-c-8_15.html
  7. Can I get a copy of the dll files?
  8. So let me get this straight; you're going to poll 256+ modbus items over 3 serials ports that will have 512+ operations over a 232/485 serial port? In the standard MODBUS network there is one MASTER and up to 247 slaves. I would not want to be in the shoes of the startup engineer on this project. Yes, it can be done. Yes, you may not be up against the serial limitations, however you're going to have a troubleshooting nightmare if just one of those devices on causes a conflict you're in a fun week or two or six... Enough of that. Let's start at the beginning: Read this and see if that fills in any gaps you may have missed. Modbus Over Serial Line V1.02 Are you using a MODBUS Gateway at all?
  9. 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.
  10. 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/
  11. 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?
  12. Yes, I've looked at the specifications for what's posted. I just want to make sure I'm not missing anything.
  13. 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
  14. 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.
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