Find out spare I/O

  • Hey guys yay for my first post.

    I've recently been put in charge of two robotic welding cells that haven't had someone on the tech/engineer side of them for almost 3 years and I'm trying to get my spare Inputs and outputs ran down so I can get a better idea of my capabilities. From the schematics that I can find I should have 10ish inputs and 4-5 out puts. from reading the wire labels and ladder logic. In the input and out put screens only some are commented out and none are commented spare or anything. the system is a R-30ib controller and arcmate 120ic


  • Not sure what is the question, but I'm assuming that you want to know if there is a way to find out what signals are "spare".

    From the robot side only thing that you can do is to go to I/O screen -> CONFIG and take a look at the mapping. Assuming that you know how many I/O you have for communication you can check if all of them are used (count how many signals you have for PLC communication), so if there will be any unassingned signals then you will know if you have spare one.
    I'm saying that you know that there are 512bits in mapping you can see only 500 assigned that would mean you have 12 left and you will know which one. However I don't think that anyone would leave spare I/O unassigned, they will just assign 512bits.

    That will leave you with robot - PLC handshake, which means triggering I/O one by one to find out if they are used or not, so you turn on a bit and check on PLC if that bit is ON.
    Here again in PLC they probably assigned all of the bits. Maybe the spare ones are named "Spare" or something like that. This is going to help you out to locate them. But again a problem occurs, I don't trust PLC guys, so they could've name the signal "spare", "reserved", ect. but still they might be using it somewhere. That would mean you need to find look for this signal in PLC program and make sure it's not assigned to anything.

    Well in KUKA for example there is a great function that allows you to look for I/O used in programs, I don't think FANUC has that option, but I might be mistaken.

    To sum up:

    1. Check I/O mapping
    2. Check PLC - Robot handshake
    3. Check PLC logic

    That should give you all of the answers. It's a long way, but it will give you 100% confidence that a signal is not used.

  • If you're curious if an I/O is being used in any of the programs, example: it is commented in the I/O list but you don't think you're using it. You can go to the robot home page and use the 'search' function and type in the syntax of the I/O you're looking for. This will search all the .LS programs to see if it is being used. Menu --> 0 --> 8(Browser) --> scroll to bottom of robot home page --> Search --> Program Search --> Type in [DO:8 (example) --> exit keyboard --> click small check box.

    I use this for older robots where things have been modified many times.

    [email protected]

  • Do you know when the Search function showed up in the Robot Home Page, which robot software version? I use it a lot on our newer robots but some of the slightly older ones don't seem to have it. One that I can think of is a M-20iA robot with V7.50P/08 software. Would it be in a software update?

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