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russedwards

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Posts posted by russedwards

  1. This is how I have my RS485 ladder setup.

    I have tried as suggested splitting my setpoint between 2 x INT16 value to write to 1010 and 1011 but I still get noting on the pressure controller. 

    Pressure from the controller is being read correctly as a REAL value

     

    image.thumb.png.3fbd9b697dee0eaeb9ed698df5e42b59.png

  2. Hello.

     

    I am having trouble with the MODBUS read / write.


    I have an empty project uploaded to the PLC, and to test communications between the PLC and my pressure controller, I have simply setup MODBUS 485 Master to communicate.

    I have setup the PLC to communicate with the controller and MODBUS link is successful.

    I am reading the pressure successfully from the controller on address 1203. The pressure is sent to the PLC without problems.

    I am trying to write the setpoint from the PLC back to the controller on address 1010 but this does not seem to work.

    I have setup a Registers Periodic operation to write to address 1010 but it does not work.

    Please could you advise what I am doing incorrectly?

    I have attached links to the Alicat documentation detailing the MODBUS settings of the controller:

    https://www.alicat.com/wp-content/documents/manuals/ModbusRTU_Manual.pdf\"]https://www.alicat.com/wp-content/documents/manuals/ModbusRTU_Manual.pdf

    https://www.alicat.com/wp-content/documents/manuals/DOC-MANUAL-MPL.pdf?_gl=1\"]https://www.alicat.com/wp-content/documents/manuals/DOC-MANUAL-MPL.pdf?_gl=1*jlekf*_gcl_au*MjAxNDI3NDk1NC4xNzA2MTE0MDQ0

  3. Hi

     

    I have a 7" UniSTream with a WCB-1 adapter.

    I am using this PLC for a very simple task of monitoring contents in a tank and then controling some relay outputs depending on the tank contents level.

     

    I have a pressure transmitter connected to a analogue input 0 and this was working correctly whilst setting up - I was seeing the correct output from the transmitter on the PLC. I also had a type K thermocouple connected to RT2 input - again during setup this was giving me a correct reading at ambient (approx 20 Celsius).

    Now, during some updating of the logic, my transducer input is showing over range constantly (16689 units when the adapter is scaled to give 16383 maximum output) and my thermocouple is showing a tempoerature reading of +4359 Celsius.

    I have checked the various status' of the WCB-1 and this is the outcome:

    IO - Status 00000000

    Analogue Input Status Input 1  (transmitter connected) - 2

    Analogue Input Status Input 1  (transmitter disconnected) - 16

    Internal Info - 363

     

    I have uploaded a blank project to the PLC, and I am still getting the same problem. Does anyone have any idea why I have run into this problem?

     

    Thanks in advance

     

  4. Hi guys

    I've been working on a project so long that I now can't see the solution to what I imagine is a simple problem. I have a v350 and I am taking a digital input to control an MB.

    I have wired many digital inputs that use the same 24vdc power supply as the PLC. But this instance I need to take a switched 24vdc input from another piece of equipment, and I cannot figure out how to wire up correctly!

    Please can someone help?!

    Thanks

  5. Hi everyone

     

    I have got myself a problem that I am having trouble figuring out.

     

    I am using a V350 as a data logger. The V350 is logging MI's, and ML's to a data table. The logging is working fine.

     

    My application requires a result to be logged every 10 or so seconds, therefore I am filling the internal memory of the V350 pretty quickly. I would therefore like to use the SD card as the memory of the logged data.

     

    I currently have a net set up in my ladder to copy the data table to the SD card when the memory is 70% full. What I would like to do is to be able to append this Data table stored on the SD card with new data as it is recorded in blocks - for example - I record 1000 lines of data to the SD card, then when the data table reaches 1000 lines again, add this new data to table saved on the SD card. I can write to the SD card each time a result is recorded if it is more appropriate.

     

    Is this possible?

     

    Also, sometimes, we may need to access this same data via dataXport. Can I download a copy of the data saved on the SD card using dataXport rather than using the SD card suite? The scheduled download function in dataXport makes it desirable for this application. We would like to download a copy of the table and leave the SD card data unchanged. 

     

    Thanks

  6. HI

     

    I have a problem that I cannot get to the bottom of.

     

    When writing a DT to an SD card, i can get the data to transfer without a problem.  Now, when I remove the SD card to transfer the data to the PC, and then re-insert the card to the V350 and try and transfer another DT, the transfer freezes and will not restart until i perform a Reset of the PLC.

     

    Does anyone have any ideas?

  7. Hi

     

    I have a V1210 using an E3XB snap in and also some remote analogue outputs.

     

    I am using an AO6X to give a 4-20 mamp output to some proportional valve controllers.

     

    Problem I am having is that one output (O4) will spontaneously send an output to the valve and release pressure - there is nothing in the ladder calling for this action.  The valve will then close again.

     

    Has anyone experienced this problem before?

  8. Hi

     

    I am having an issue with some email alerts that I am trying to send from my V570.

     

    I am looking to combine direct and indirect email content into the same message, is this possible?

     

    For example, at a set time, I want the PLC to send an email saying eg "your current drum volume is 257 litres".  

    The wording "your current drum volume is" - is the direct email content, and the 257 is read from an MI and is therefore the indirect content.

     

    Is this possible?

     

    Thanks

     

    Russ

  9. Hi

    I have been looking into the new UniStream equipment and I am very impressed!

    Can someone shed some light on the Date / Time / UTC structs?  It currently seems very long winded to use a date or time function within the ladder, but the help folder says that an included date / time struct is available.  Can someone point me to where this is?

    I'm looking to write the date to a data table, with Visilogic this was a simple RTC to ASCII task.

  10. Hi guys

     

    I am looking for a bit of help regarding the Transistor Outputs of my E3XB snap in module.

     

    I have made a mistake when planning my current project and have left myself 1 relay output short.  I am controlling a simple on / off 24 vdc solenoid valves with all the outputs of the E3XB.  

     

    Is it possible to control a solenoid valve with the transistor output in the same way as a normal on / off relay output?  If so, how can I go about it?

     

    Any input would be appreciated!

     

    Thanks

     

    Russ

  11. Hi

     

    Has anyone got any suggestions to my current problem?

     

    I have succesfully used Arkadi Samarov's DHCP application to connect a V570 using DHCP and a mac address.

     

    Is it possible for DataXport to connect to the V570 using the mac address rather than direct IP address?  I am finding that when the lease is renewed on the V570 and the IP address changes - i have to manually reconfigure dataxport to reconnect.

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