Client Tag change script

Ignition
1

Hi, i need to know when i select 2 tags in tag change script how do i access the second tags like
first tag value i will access via
print event.tagPath
print initialChange
print newValue
but how to take new Value of second tag which i have used in tags.
Urgently needed.

script
script947×591 101 KB

tags
tags1171×390 26.1 KB

2

These events fire for each tag that changes value in those you specify. When it fires, it fires independently for each tag being monitored changes; you don’t get access to other tags being monitored. You will need to read any other tag by using a static path to them and system.tag.readBlocking. In this respect, the gateway tag change scripts behave very similarly to tag change scripts

3

i am trying to read the tag but it is not working so can you tell me the exact syntax for read.
I am trying with system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl").value
but still i ma unable to read that

4

It returns a list, so you need
system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl")[0].value

5

that syntax is not working in script as i have tried. Also want to know what this [0] stands in syntax

6

When you say it’s not working, what do you mean?

The [] are basic python syntax to read the elements of a list (array). If you’re asking that question though, you really should look at some basic introductory material to the Python language. I think even the IA user manual has some material covering it

https://docs.inductiveautomation.com/display/DOC81/Python+Scripting

7

yes sure i got the list of array, but still i am facing the same issue i am posting the query and image.
below image is the tag for which i created script.

tag
tag1350×375 18.5 KB

the tag is timer tag and i am changing the process based on conditions and timer value.
and below is the code for the process.

print event.tagPath
print initialChange
print newValue

if system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl")[0].value == 1:
system.tag.writeBlocking(["[default]FB_Process/Test_tags/Timer_tag"], [1])
if newValue.value == 1:
system.tag.writeBlocking(["[default]FB_Process/VLV4/Mode"], [1])
system.tag.writeBlocking(["[default]FB_Process/VLV4/Valve_status"], [1])
system.tag.writeBlocking(["[default]FB_Process/VLV7/Mode"], [1])
system.tag.writeBlocking(["[default]FB_Process/VLV7/Valve_status"], [1])
system.tag.writeBlocking(["[default]FB_Process/BL01_Filling/Fill_ctrl"], [1])
system.tag.writeBlocking(["[default]FB_Process/IT02_Empty/Empty_ctrl"], [1])
if newValue.value == 5:
system.tag.writeBlocking(["[default]FB_Process/PU2/Mode"], [1])
system.tag.writeBlocking(["[default]FB_Process/PU2/Pump_status"], [1])
system.tag.writeBlocking(["[default]FB_Process/Test_tags/Timer_tag"], [0])
newValue.value = 6
if newvalue.value == 6 & system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl")[0].value == 0:
system.tag.writeBlocking(["[default]FB_Process/PU2/Mode"], [0])
system.tag.writeBlocking(["[default]FB_Process/PU2/Pump_status"], [0])
system.tag.writeBlocking(["[default]FB_Process/Test_tags/Timer_tag"], [1])
if newValue.value == 11:
system.tag.writeBlocking(["[default]FB_Process/VLV4/Mode"], [0])
system.tag.writeBlocking(["[default]FB_Process/VLV4/Valve_status"], [0])
system.tag.writeBlocking(["[default]FB_Process/VLV7/Mode"], [0])
system.tag.writeBlocking(["[default]FB_Process/VLV7/Valve_status"], [0])
system.tag.writeBlocking(["[default]FB_Process/BL01_Filling/Fill_ctrl"], [0])
system.tag.writeBlocking(["[default]FB_Process/IT02_Empty/Empty_ctrl"], [0])
system.tag.writeBlocking(["[default]FB_Process/Test_tags/Timer_tag"], [0])

8

Try this. You had a few typos (like using newvalue instead of newValue), you can’t write to newValue.value, also I converted your individual tag writes into single block writes as this is a lot more efficient in terms of CPU and speed.

print event.tagPath
print initialChange
print newValue
tagPath = str(event.tagPath)

# this will store the tags and their values to write as a list of lists as [[tagPath1, value1], ..., [tagPathN, valueN]]
tags = []

if system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl")[0].value == 1:
	tags.append(["[default]FB_Process/Test_tags/Timer_tag", 1])

if newValue.value == 1:
    tags.append(["[default]FB_Process/VLV4/Mode", 1])
    tags.append(["[default]FB_Process/VLV4/Valve_status", 1])
    tags.append(["[default]FB_Process/VLV7/Mode", 1])
    tags.append(["[default]FB_Process/VLV7/Valve_status", 1])
    tags.append(["[default]FB_Process/BL01_Filling/Fill_ctrl", 1])
    tags.append(["[default]FB_Process/IT02_Empty/Empty_ctrl", 1])

elif newValue.value == 5:
    tags.append(["[default]FB_Process/PU2/Mode", 1])
    tags.append(["[default]FB_Process/PU2/Pump_status", 1])
    tags.append(["[default]FB_Process/Test_tags/Timer_tag", 1])
    tags.append([tagPath, 6])
    
elif newValue.value == 6 and system.tag.readBlocking("[default]FB_Process/IT02_prodtransfer/Prodtransfer_ctrl")[0].value == 0:
    tags.append(["[default]FB_Process/PU2/Mode", 0])
    tags.append(["[default]FB_Process/PU2/Pump_status", 0])
    tags.append(["[default]FB_Process/Test_tags/Timer_tag", 1])
    
elfif newValue.value == 11:
    tags.append(["[default]FB_Process/VLV4/Mode", 0])
    tags.append(["[default]FB_Process/VLV4/Valve_status", 0])
    tags.append(["[default]FB_Process/VLV7/Mode", 0])
    tags.append(["[default]FB_Process/VLV7/Valve_status", 0])
    tags.append(["[default]FB_Process/BL01_Filling/Fill_ctrl", 0])
    tags.append(["[default]FB_Process/IT02_Empty/Empty_ctrl", 0])
    tags.append(["[default]FB_Process/Test_tags/Timer_tag", 0])

# write the values to the tags. Note the syntax "list(zip(*tags))" effectively produces a list of columns, where element 0 are the tagPaths and element 1 are the values
system.tag.writeBlocking(list(zip(*tags))[0], list(zip(*tags))[1])
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