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Simon last won the day on August 20 2020

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    Unitronics Distributor

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  1. What is showing on the screen of the HMI? I suggest you contact your local distributor, and Unitronics support.
  2. Try unplug/re-plug the USB. Also try cycling power to the PLC. Just while you are working with getting started, i would also try any example that is already written for the 570. I see you have a V120 example opened.
  3. Try setting the baud rate to 115,200. That is the default value for the V570.
  4. Have you tested comms after installing the driver? I know those windows messages look concerning, but I'd just check and see if it's working. Also try unplug/re-plug the USB and/or a restart of the PC To check the comms: Go back to the Connection -> Communication and OS dialog. Select COM3, click Get OPLC Information
  5. Hi Tim, Good to have Unitronics confirm that. I suspected it was the case but have never tried it. Simon
  6. Hi Tim, Good to have Unitronics confirm that. I suspected it was the case but have never tried it. Simon
  7. No worries, your post came before Tim posted about the masters both being PC-based.
  8. I would definitely try a test setup with two ModbusTCP masters polling the single UniStream slave. As I said it may just work exactly the way the V230 has been working. If you don't have the actual masters, then test with a PC based emulator. I took a quick look and see what you mean about setting up two Modbus configs and two Scan EX blocks in Visilogic. Easy to do. If you used UniCAN you would need CAN modules on all PLCs. But you say you are using a windows PC as the master, so I don't think CAN is the right option. It's frustrating that a newer version doesn't do what the old one did. If you want to push it further with Unitronics, then yes I would open a support ticket. Hope this helps, Simon
  9. Hi Tim, Unilogic doesn't support 2 slaves on the same protocol. Since it's ethernet you may find that the two masters can connect and each poll the same slave without issue, this would depend on how rapidly the masters were each polling the slave. This would definitely be a problem on RS485, but Ethernet can handle some level of simultaneous requests. I suspect if both masters made a poll request at the same time, one of them would be buffered until the other one was answered, then the buffered request would be answered. I understand if you want a more tightly engineered solution, and for that you would need to add something external like the Moxa Mgate product that can allow multiple masters to access a single slave.
  10. It is possible in any way to download log files via the Unistream built-in webpages? Firstly I see that the file browser widget is not yet supported in the web page editor. However is there another way to embed a log file into a hyperlink on the screen, so the user can just click on the link to download the file into their browser? The specific application is energy monitoring and logging, and many self-contained off-the-shelf systems have this type of interface. They often run on Javascript engines or similar. Thanks, Simon
  11. Yes, it is unclear what you are trying to do. As @Flex727 has said, there is a Toggle Coil which could be used with your Timer as below. User has to hold the button for the length of the timer to turn on or turn off.
  12. Hi Mel, I can't see a system function for this, but each HMI screen has the optional "Is Active" tag (bit type). Are you looking for a way to monitor an existing project, or creating from scratch? Obviously this requires a program change if you are working with an existing project. Simon
  13. Hi, these are just my quick comments, but one key thing with autotune and heaters is to choose the right setpoint. The autotune can get "stuck" or just take a really long time if the wrong setpoint is used. Autotune drives the process to the setpoint, then applied alternative step changes to the setpoint, about 5-10% above and below the setpoint. It measures the step response of the process to these changes in setpoint. For example, if your ambient temp is 23° C and you choose a setpoint of 30°C the process will ramp up nicely to 30° (or 33°). However for the negative ramp (back to 27°) it will take a very long time, especially if the process vessel is large and/or insulated, as the difference between the process temp and ambient temp is very small. On the other hand, if the process temp is 90°C and the vessel is relatively small and uninsulated, the autotune will cycle much faster, as the vessel is able to lose heat quickly once the heater is tuned off. Hope this makes sense, it seemed like a complete mystery to me until I worked through it. My desktop test system is a 5W ceramic resistor inside a plastic cup 🙂
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