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Check out the list of all tutorial videos on the C-More Micro HMI at this link:
When we press the pushbutton on a C-More Micro, a message is sent to update the associated TAG – usually on a connected PLC. In this example this Push button is setup to toggle Control Relay bit C201 on a Click PLC which is simulated here in the Control Window. That’s a key point – this pushbutton switch doesn’t actually turn anything on – it just sets a TAG and then it is up to the PLC to see that and do something about it. This push button is setup to act as a toggle – each time I press it, it toggles the state of the TAG which you can monitor here in the control window. Press it once to turn it off, press it again to turn it back on. The push button can also be programmed to act as a Momentary switch or a Set On, Set Off type of switch. Let’s do a few examples to see how to set this up. If you see a push button you like down here in the parts list, just drag it onto the screen – it’ll save you from setting it up yourself. We’ll start from scratch in this example so Double click or drag the pushbutton on to the screen. First, we need to tell the Pushbutton which TAG to modify – we’ll just grab one out of the projects Database since they are already setup – how about the FAN TAG. Even though there are a lot more TAGS in this project – we only see the discrete TAGs in this list – that’s because the software recognizes that this is a simple on/off switch and knows that we don’t need to see all of the other TAG types. If you want to see them, just click here to bring up the entire TAG database. Second, format the look of the switch – check out the video on How To Use Common Object Features for tips on how to do that. Third, select the switch action. We’ve already seen how the Toggle switch action toggles the TAG on and off, so let’s do a Momentary-On switch and see how that works. Let’s also give this button a label: let’s enable the label feature… change the label to FAN. Notice that all the things you do to the button are simulated in this little this little window here and that you can actually test it while you are in the dialog. That result is also reflected on the button on the screen. Looks like we are all setup so we hit OK, Simulate. Save the project. And up pops the simulator with our new push button object. Now you can see that this FAN TAG is set to ON as long as I hold the button down. As soon as I let go of the button, the TAG turns back OFF. That’s our momentary switch action. If we had picked the Momentary OFF switch action, it would have changed the TAG to OFF and held it there as long as we when we held the switch down. Double click on the object to bring the dialog back up. Since this TAG starts in the OFF state, let’s change the switch type to SET ON. If we change it to SET OFF, The switch would send a message to change the TAG to OFF when pressed, but since the TAG is already OFF, the switch will appear to have no effect, so be careful with that. We’re using the Set ON action so we’re good to go. We say OK, Simulate. Save the project, and up pops the simulator with our new SET ON action. Now when we click on this SET ON switch, the tag gets changed to ON and the button is now set in that position. This is a really great option when you want the PLC to be in control of the switch action. For example, Using this SET ON switch, the user can enable a process like we just did here, but can’t re-enable that process until the PLC resets the TAG. I’ll pretend I am the PLC and set this TAG to OFF. Sure enough the Pushbutton is now re-armed and ready to go again. But, once the user presses it, he can’t re-enable the process until the PLC is ready. So now the PLC has control over how often the user can enable this process. That’s it for this video – be sure to check out all of the other videos in this series. And as always, please send us any topics you would like to see covered – or - any other comments for that matter – we appreciate the feedback!