PLC going into program mode by itself

[Lem]

Originally Posted by I_Automation

My home automation system (1 SLC5/05, 3 5/03's, 1 5/04, 1 ML1400, 2 Siemens S7-200's) controls about 140 circuits of Christmas lights and 40 circuits of Halloween lights along with 7 security lights, gate locks, fire and flood alarms, solar battery charging, 6 outdoor outlets controlled, 6 temperatures monitoring, electric blanket control, power changeover for air conditioner compressor when the controlled meter is turned off, slow cooker control, and more. Plus a fully functioning traffic light with left turn lights, Walk/Don't, Prepare To Stop When Flashing, School Speed When Flashing, antenna tower lights, block control and street lamps for a model train set I haven't built yet.

#LifeGoals

That makes my home automation setup look tiny and amateur haha, Nice!

[plvlce]

Someday maybe I will build a real home automation setup.

It won't be Rockwell though.

[lostcontrol]

Originally Posted by I_Automation

Here's a shot from my home automation SLC of how I change setpoints

What's to stop someone writing to the HMI SP, without your knowledge?

[drbitboy]

Originally Posted by lostcontrol

What's to stop someone writing to the HMI SP, without your knowledge?

Maybe I am not understanding the question, but nothing: the point of that logic is that any HMI SP value outside the acceptable limits will be rejected.

[lostcontrol]

Originally Posted by drbitboy

Maybe I am not understanding the question, but nothing: the point of that logic is that any HMI SP value outside the acceptable limits will be rejected.

yeah I get that part.
I interpreted this logic as a response to Mr Bubba having a HMI in their locker for changing values etc (post #11)
But when I re-read it, this logic would solve the limits issue that would be imposed by the operator HMI

[Kefren]

Thanks guys for all the tips, for sharing your experience.

Until now this remains in mistery for me, i could not find the reason why this happened.

Now the keyswitch is in RUN, every time I need to do online edits i switch to REM, do the things, and return to RUN.

[I_Automation]

Originally Posted by lostcontrol

What's to stop someone writing to the HMI SP, without your knowledge?

Writing to the setpoint without writing the same value to the HMI_Entry tag on the same scan will result in the PLC using the unchanged HMI_Entry value and resetting the setpoint back to what it was whether it's within the limits or not.


Writing an out of limits value to the HMI_Entry by a rouge HMI will result in the entry ignored and rewritten back to the existing setpoint.


To not allow a bit be toggled I have latched a separate 'register' bit and only when properly toggled by the HMI pushbutton will BOTH bits be toggled, if the usage bit doesn't match the register bit then it gets toggled back.

[BryanG]

Is there any reason nobody suggested that maybe the switch is faulty?

[mad4x4]

You have had a brown or a back out on that system!

For Recokwelll - Check the Power on rules, if key is in program and you set it to remote via software then it when it next powers on it will start up dependant on the published rules and the key position.

Can't remember the exact rules but sure it was always set it to run (key) then turn back to RunP so it starts in Run rather than Stop. Before leaving site and leaving it in Remote mode.

[drbitboy]

Originally Posted by I_Automation

... a rouge HMI ...

Like this?

2711PT10C21D8S.png

(sorry, couldn't resist ).

[plvlce]

Originally Posted by drbitboy

Like this?

Attachment 64210

(sorry, couldn't resist ).

No need to be sorry, it's very important we not confuse it with a burgundy HMI.

[I_Automation]

I'm actually not sorry the guy that invented spellcheck past away and his funnel is tomato


Anyway I was thinking of more like this: (the HMI not the screens)