Fran Posted January 29, 2021 Report Share Posted January 29, 2021 I have Unitronics HMI and I/O modules at home but not the actual machine (it wouldn't fit in my kitchen).I would still like to edit and test the software. I can't force the analog I/O and test the software. I can tell that the alarms for pressures and levels are working :). How can one force the analog I/O? Link to comment Share on other sites More sharing options...
AlexUT Posted February 1, 2021 Report Share Posted February 1, 2021 To force Analog Output, you have to write into linked memory register (MI, ML, DW)value you wish to force. Use intermediate register to force output. MI 3 linked to AO. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted February 1, 2021 MVP 2023 Report Share Posted February 1, 2021 You can also write the value directly into the linked MI when online if the I/O is NOT connected to the PLC. If your PLC has no onboard I/O, simply don't connect the I/O then you can go online and write values as you wish without having to modify your program. Remember that you are writing the analog-to-digital equivalent value. You will need to know the resolution of your analog input (10-bit, 12-bit, or 14-bit) to know the range of values to use. Or in AlexUT's example above, you could add in a linearization function to allow you to enter the analog value directly. Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted February 1, 2021 MVP 2023 Report Share Posted February 1, 2021 If in your configuration present not used ANALOG INPUT and ANALOG OUTPUT - you can build online hardware simulator for analog I/O. SImply connect not used ANALOG OUTPUT (defined in hardware in needed mode) to tested input and you can write to this port different value in online mode or program some subrouting for generate needed level changing in time. For examlpe - increment and decrement simulated pressure to test alarm screen. If you need to see what happend on analog output - connect it to not used ANALOG INPUT and place on screen output value. You can see real signal on output without multimeter. P.S. Now i build hardware PLC based simulator for test PLC based machine control system in mass production without connecting analog sensors and another hardware. Then you can use spare PLC for test analog I/O. Link to comment Share on other sites More sharing options...
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