Multiple trigger

Ignition
1

I am attempting to set up an expression that will look at the time and set the trigger value when the time is 7:28 AM or PM. At the same time, I need to set the trigger flag on the haschanged for another PLC value. From what I gathered, this was suggested in another post, but i could be confused on the basics of it. I am also confused with the Python syntax and the whole process in general. I have tried a number of variations to the syntax.

I keep getting an evaluation error on both expressions. Here is the time check expression:

if {[.]Hour}= 7 || {[.]Hour} = 19:
	if ({[.]PLCMinute}= 28):
 		{[.]Trigger)}= 1
else:
 	if (hasChanged {[.]MainMotorRunning_4}):
 		{[.]Trigger)}= 1
	else:
 		{[.]Trigger)} = 0)

Can you help?

2

Indeed, that's your first problem- there should be no python involved :smiley:

Ok, so you have a trigger in a group- it's an Expression Item named "Trigger", which uses expression sytanx. The difference between the two systems commonly trips up new users, and I wish we had a video outlining the two, but for now there's this section in the user manual.

So then, in expression syntax:

if( ({[.]Hour}= 7 || {[.]Hour} = 19) && {[.]PLCMinute}=28, 1, if( hasChanged({[.]MainMotorRunning_4}), 1, 0) )

You were trying to assign a value to "Trigger". This is not how it works- instead, your tag "Trigger" is set to run as an Expression, with the code above. All expressions always boil down to a value, so what we have above is an "if" expression with a nested expression in the "else" case. Here's the user manual entry for the if function, if it's not clear what's going on in that block.

Hope this helps,

3

That was it! && I tried the book method If( condition, trueReturn, falseReturn) and I couldn’t seem to incorporate the minute value into the condition so strayed off into python land to try to fix it.

Thank you Colby!