Omron NJ Performance Issue

Hi, I’m currently working with a customer who uses Omron NJ101-9000.
They have approx 1500 tags in their PLC, most of them are “struct” based. When adding the tags to ignition, I can add about 70 tags, before the loadfactor goes bananas.
I have tried to adjust concurrency etc, but the only thing that help is to increase the scanclass. Is this how the NJ Driver ( CIP ) is designed, or is there some other setting that might help me reduce the load?

Here is a screenshot of the current status:
Concurrency : 2
CIP Size : 1994

Your mean response time is the critical factor here. That processor is getting hammered somehow, and can’t quickly process the requests. That response time should be in single digit milliseconds. I’m not familiar with the details of the NJ, so I can’t be more specific, unfortunately.

Hi,
I found what worked quite nicely was actually setting up two OPC Devices in the Ignition Gateway. These can connect to the same PLC IP address, and even have the same tag table.
But if you split out your tags in Ignition to use half of each device, you should see some improvement.
Depending on your tags you could split between Analog and Digital or something to keep it simple.

The other thing that helped a lot was checking the task time of your primary task. If you don’t have much free time in your task cycle, the NJ will struggle to service external communication requests.

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Thank you for the feedback. The primary task was running at 1ms, so no wonder the PLC didn’t have time for external requests :slight_smile: Made them increased the primary task to 4 ms, and it’s now running smoothly with 1500 tags.

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