Plc update tag late

Ignition
1

Hi Team,

We are experiencing an issue where pressing a button to toggle a motor ON/OFF causes a noticeable delay—sometimes around 2 seconds, and sometimes even longer.
The PLC we are using is an Omron device.

Does anyone have any suggestions for how to reduce this delay or improve the responsiveness?

Below is the code currently used on the button’s onClick event:

def runAction(self, event):
    tagPath = "[default]_Plc_sch_/Sel_agt_pol_01"
    currentValue = system.tag.readBlocking([tagPath])[0].value
    newValue = not currentValue                    
    system.tag.writeBlocking([tagPath], [newValue])

Thanks.

2

Please see Wiki - how to post code on this forum. You can then edit to fix the code block formatting. Thanks.

3

It is done. Now please answer the real question.

4

Blocking tag writes are safe in tag event scripts only for memory tags. Any other kind of tag will delay for confirmation of the write.

5

You should be binding your desired tag instead of using a script to do read/write blocking. This should be more efficient and performant than the way you're doing it.

6

i have tried to bind with toggle switch as you advised but result are same.
We have tried updating the Timeout in the Gateway; however, when reducing it from the default 2000 ms to 1000 ms, the PLC did not respond at all.

7

Go to Gateway webpage, status, devices, your Omron. It sounds like it is overloaded. Post a screenshot.

8

You are right. now what is the solution?

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image1499×673 44 KB

9

Reduce the poll rate on tags that don’t need to be fast. Split them into separate groups.

However, only 17 items, that is a wimpy CPU, or you have severe network latency issues.

I’ve never used Omron with Ignition, so can’t propose much further. Phil Turmel Automation Pro’s has an alternate driver I think, which may yield better performance.

10

@pturmel
”Phil Turmel Automation Pro’s has an alternate driver I think, which may yield better performance.”
Could you help us resolve this issue?

11

What CPU are you using?

12
13

The CPU of PLC is NX102-1220

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image142×187 19.7 KB

14

Then you’re in luck.

15

The NX102 also has onboard OPC UA support, which might be another direction to explore.

1 Like
16

Please remember that we're almost all volunteers on this forum, giving freely of our time and expertise. This sort of post doesn't entice me towards offering support.

7 Likes
17

From a few reports, it isn't much faster than the IA native driver.

I've had difficulties with the NX family reported with my driver, but without any details to poke at. (I do not have an NX in my lab, so a lab rat would be helpful.)

Those who have used my driver have reported performance in the 30x to 50x range compared to the IA driver, which correlates well with my experience with the NJ501 in my lab. Also note that my driver auto-browses the PLC--no export from Sysmac Studio required. (With a few nuances described in my user manual.)