HMI Pushbuttons & PLC logic behind it

[mattykuz]

Hello,
Im new to PLC and HMI programming. I dont have to use it much but since I come across them at work often I might as well understand how to write some basic stuff.

I set up a test bench at my desk.. Has a Panel PC that runs wonderware (I used Intouch Machine addition to program) and a controllogix PLC programmed with rslogix. I was able to get everything talking and wrote a basic start stop latch string in the PLC, exported tags to intouch and can control a pilot light on the hmi with an on and off button and see the tags toggle when online with PLC. This is a bad way because I cant figure out a way to keep the off button high.

There is a pushbutton in ITME which I have tried but have not had luck with. Gives me a few tag boxes to fill in but I dont understand what should go where.

-Tag/Expression
-Disable
-Indicator

So if I have a few tags...say Button1, Button2, Light1 where Button1 is on and Button2 is off which tags should get put into the boxes for the puchbutton? Ive tried a few different ways and cant figure it out.

Thanks in advance for any input. Also recommendations for things I can try to get working next would be cool too.

 

[danatomega]

-Tag/Expression - this is what the button turns on / off when you depress it
-Disable - this is a tag that you could use to disable the button so's the operator can't use it
-Indicator - this is the tag used to illuminate the button like when you turn something on and you want the button to light up

 

[mattykuz]

hmm okay. For the indicator, can that just be the light tag? So when the tag gets toggled it will turn the light on and the button will also see it and light up as well?

It also has options for Type: Momentary, Maintained, and Latched and State: Normally Open and Normally closed... Should it be Latched since I want the light to stay on until I press the button again?

 

[danatomega]

The indicator would be just the light tag in your case.

Normally, I use momentary with the logic for the light being seal-in type logic (I don't use actual latched coils much).

Read the help file on Maintained & Latched.
N.O. or N.C. depends on your PLC logic.