SteelBlue48310

It is a M91. Oh well... I might have found the issue anyway, but it would be cool to single-step the code. Thanks Dan and Lawry!

Is there a way to set the PLC to run in a 'step' mode for debugging purposes to make it go one net at a time and watch it via the Debug screen? I seem to have a situation where something is happening faster than I can monitor with the normal Debug screen.

I didn't know about the Indirect 'Load' function... until now! (I was trying the Indirect 'Store') Anyhow, I tried that 'special' function, and I still can't get it to work. I could post the code, but for now I've decided to tell my customer that what they want isn't possible, and that they will just need to push a button to cause the desired effect to happen. (I was trying to 'Automate' a reset of a few values after a certain set of conditions had occured) Thanks for your assistance! ~Mike

Thanks guys. This isn't a linearized value that I need... or a value that gets displayed on the HMI screen. I'm using an 'indirect store' function to point to a single MI from several other MI's, and I need to use the value of that 'stored' MI somewhere else. There are 20 different MI's that I want to pick from, based on that Indirect store. That's why I thought maybe a 'variable' is what I need to reference... I keep getting the 'number' of the MI itself, and not the data within it... perhaps I'm using the indirect store function incorrectly?

Is there a way to reference a 'Variable' on the ladder for Compare or math functions?

Michael_P to the rescue! Thanks to his efforts and some more thinking on my part, based on his ideas... it works! Many thanks guys...

Thanks Michael_P... I put in the Set /Reset output, but now I have issues with the logic. Can I post this project somewhere so someone can look at what I've done and offer suggestions as to how to make it work? I am hesitant to just put it up for the general public, as I hope to make this into a 'for sale' solution. It will take more than a few paragraphs of typing just to describe how it's supposed to work! ~Mike

I have an idea for a new 'feature' for the U90 Ladder software... how about a way to 'copy' a net on the ladder from one project to another? I have seen plenty of good ideas in the 'sample' projects, and my own, but I can't just copy a selected net (or more than one) and then paste to the one I'm working on. I see the export / import functions do this, but maybe an alternative is just a simple copy / paste?

OK... the encoder is working, and the display is showing the correct values. The problem I'm having now is: I have a 'compare' function that fires an output (Output 0) if the value of the count is between two other values. That works if I only have one 'net' (rung) that does the compare and output... but, if I have more than one net that fires the same output, the first one never fires. (actually the output can't be fired at all, even in 'online' mode) I would certainly hope that I could have more than one instance of the same output on many different nets... it's as if the second net is inhibiting the first, and so on. ~Mike

Thanks, Simon! What I ended up doing was to use a simple compare function, to check if the 'previous' screen (and variable) is equal to zero, then set the current display to be the 'ending' screen... works great! I am waiting for a shaft encoder to arrive to try the next part of this project... I'm sure there will be more questions! ~Mike

Hey all... another new project for the M91-2-R1... I really like this device! Anyhow, I'm having trouble with what I thought would be a 'simple' HMI task. I have setup a number of 'display' screens, each with a numerical input variable. I then created 2 'jump conditions' on each screen... one that advances the display 'number' to the next screen for additional inputs, and a second condition that "ends" the inputs if the Zero Key is pressed. For some reason, the 'jump' if Zero is pressed isn't working. I even tried a Ladder (net) that has a P (rising) contact to change the display if Zero is pressed... no joy. Ideas to try? ~Mike

Got it working... I used a 'direct store' of the current value of the analog input, and then compared that to the new input and fired a 5 second timer if they were different. Just had to think a bit more!

OK, new problem to solve... I am really stumped trying to solve a logic issue with my M91 project. Here's the scenario: I have an analog transducer that is mechanically tied to a piece of machinery that moves in a linear motion. (Up and down) The M91 shows the relative distance from the floor, in inches... and I can set a 'new' height value which causes an output to energize that closes a motor contactor to run a motor to move the machine up or down. That part all works great. What I am struggling with is the logic to display a message in the event of a failure to actually move the machine, for a variety of reasons. The hard part is that the machine moves *very* slowly, and can take as much as 10 minutes to move from the lowest point to the highest point.... but, I want the 'failure' message (display) to occur if there is no actual movement within 5-10 seconds. With the 'math' and 'compare' functions that I have available to me in the M91 ladder, I can't seem to find the "right" methodolgy to make this work! Any ideas would be greatly appreciated! ~Mike

Thanks Emil! This was exactly what I needed. The project is finished and working just like I had hoped.

Got this to work since the last post.... I also now realize that the input is 10-bit resolution, so disregard that comment. Now I'm working through another issue. Trying to get the actual 'displayed' value to be represented somewhere in memory so I can use a compare function to be similar to a value that is entered via the keypad. (It's because I am now scaling the values)