Colleagues, I’m on a situation where some Ignition tags are taking a long time to have their values updated. The application currently has 10 devices, all 1756 l83e Controllogix 5580 Controllers, and all connections configured using Allen-Bradley Logix Driver. I have 2 devices with more than 21000 tags which are showing overload os 168% and 110% for tags Sampled at 1000ms. Others are fine, including one with 11000 tags which shows 5% overload. I used UDTs for most of the AOIs and some of them were moved to Leased Tag Group with no significant improvement. Also, increased CIP Connection to 4000, not a big difference. I’m trying to figure out what could be happening, reading through the forum I saw similar situations, but I can’t increase all tags to a higher sample rate. Need your help guys!
This is the issue, reading aoi tags will always be slow and inefficient. Reading UDT tags however will be fast. Let me dig up another post..
This while topic is super useful, but my post linked shows a table of performance for reading different types of tags.
What's your cip connection size set to in your device connections in ignition for those plcs? It should be set to 4000 not the default 500
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CIP connection size and number of connections. AOI tag access will severely slow down the driver. Also, did you judiciously create UDTs on the Ignition side and are polling tags you only need, or did you drag the Logix global controller and all tags into your tag provider?