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Simon last won the day on August 20 2020

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    Unitronics Distributor

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  1. 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
  2. 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.
  3. 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
  4. 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
  5. Hi, It's all about the reference point. First let me say, with the outputs, the diagram you post is consistent with how i've summarised it. Regarding the inputs, the diagram you post is showing everything relative to the PLC, which is opposite to how I have summarised it. So for the PNP input, the external device (sensor, switch) is sourcing, and the PLC input is sinking (current flows from the external device into the PLC input) for the NPN input, the external device is sinking, and the PLC input is sourcing. (current flows from the PLC input into the external devic
  6. Hi, I think you have the sensor side back to front. Below are two diagrams from 2 brands of sensors. The PNP sensor is connected between +24V and the PLC input (load) and the NPN sensor is connected between 0V and the PLC input. It's the opposite for outputs. The terms Sinking and Sourcing often get used, and that can also be confusing without the right reference point. It's better to think in terms of current flow rather than voltage. The sinking and sourcing of current is relative to the signal driver. And for the purists, we are talking conventional current not electron
  7. Hi Mark, Welcome 🙂 Try pulsing SB31 after updating the vector of MIs. Make sure it's a one-shot pulse, not a direct condition. Simon
  8. Sorry, I missed all this. Thanks for the tag @Ausman Hi @EladLending The example posted by @Joe Tauser follows the approach I would use. A variation would be to put all the code for each machine state inside a subroutine, to separate the application code from the state machine logic. However that's just an efficientcy and style question, the underlying structure and flow doesn't change. There is no access to the system "program pointer" or anything like that. In Joe's example the "pointer" is MI0. It is explicitly set up and controlled by the ladder application. Hope this
  9. Bootlace pins only apply to the modules with standard industrial wiring connections. The high density modules (32-channel digital I/O and 8-channel temperature) use a pin header as @Joe Tauser has pointed out. I got caught by this when supplying an 8-channel thermocouple input module. The most reliable way to tell from available information is to look in the user manual for the remote IO modules, from the Unitronics technical library. There is a model listing around page 9 or 10 (the doc gets updated, so page numbes may change over time). After the produduct description is an indication o
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