How to display a Major Fault on a HMI?

[JesperMP]

The way you describe it, the second-best solution is a prominent green lamp and a prominent sign "only start loading if the green light is lit". The lamp must then be controlled by the PLC.

We have had the problem that there were multiple connection points going each to its own silo. If the truck driver inadvertently hooked up to the wrong silo it would be a small catastrophe. So we had both lamps and a safety valve to prevent it from happening.
Using a HMI for this function isnt failsafe enough. Even if the HMI works ok, it is too easy to make a mistake if you are in a hurry. A valve directly on the pipe (or lamp right next to the hook-up point) is much better.

 

[Old No. 7]

FWIW, I did this with a Red Lion G310 and Micrologix 1400. I have a popup that automatically appears if there is a PLC fault and it displays the fault codes (it also appears on a communication loss). In the case of the ML it was pretty easy, you just read the S2 values. I have not tried this with the Compactlogix though, so it might not be possible.