Truman E Posted November 21, 2018 Report Share Posted November 21, 2018 Good day, I need a few pointers. I am fairly new to Unitronics and the UniLogic systems. I have some experience with ladder logic from past projects, the most recent of which used the Keyence ladder builder software. It’s like coming out of the Stone Age! If I need to separate this into sections please let me know. I appreciate any guidance you can provide. I am working on a project for a production machine. The machine is utilizing modular design from discrete components that can function on their own, so I am somewhat limited on my approach options. I will try and outline what those are as I go along if they are important. I’m using a USP-156-B10 with a WCB1 and a UID-0808R with the latest software available (as of 11/21/18). Currently, I have three items to review. I think that will be all I need help with, as the rest of the control program is very straightforward (now). Item 1. I need to write code for a change over time function. I am reading off of a motor drive encoder which I need to ensure is at 0 speed (stopped) before advancing. As the drive is not a servo, and the drive could stop with the encoder reading high or low, I need a change in condition over time. While it is simple to say, I have not found a solution working through the manual or the examples but it is possible I missed something. Ideal logic is: no change in state (can be high or low) for x amount of time (x being relatively quick, perhaps .1 sec), in a continuous readout (no reset if possible to allow for continuous operation) that would change the status of a binary variable (stopped or not). Item 2. I have not found an incredible wealth of knowledge dealing with the application of analog outputs. I am in a position to write this section a few different ways. The analog output can be in mA or V, as we are using a signal conditioner to isolate the PLC from the motor drive controller. If the value of this were to remain constant I could see some options to directly output, but we may need at least a two-stage output (one speed forward one speed reverse) as we can control accelerate and decelerate through the drive controller. I imagine that the same function could just be duplicated for as many states and drives as are necessary. The target speed should be settable via HMI interface, with a slider bar going from 0 to 100, but the real output needs to be limited to 9V, not 10V (or 90% on current). I do not readily see how to code this. Item 3. I might already have an idea on how to do this, but I want to know the best practices. Upon recovering from an emergency stop I want to give the user the option to either return to “home” or to resume the operation. Either way, I need to make sure the machine either completes the cycle or is reset to its initial state. My previous mentor had some unorthodox methods, which I will not take the time to elaborate here. Again, looking for what is the best practice. Thank you in advance! Quote Link to comment Share on other sites More sharing options...
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