# To UDT or not to UDT. That is the question **URL:** \ **Category:** Ignition\ **Tags:** ignition80\ **Created:** [February 28, 2020, 6:04pm UTC](https://forum.inductiveautomation.com/t/to-udt-or-not-to-udt-that-is-the-question/32703 "2020-02-28T18:04:28Z")\ **Posts on this page:** 3\ **Page:** 2
**Author:** ![ziad](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ziad/32/6841_2.png) [@ziad](https://forum.inductiveautomation.com/u/ziad)\ **Post date:** [March 6, 2020, 8:03am UTC](https://forum.inductiveautomation.com/t/to-udt-or-not-to-udt-that-is-the-question/32703/21 "2020-03-06T08:03:12Z")
Agreed. Yeah, we have some bulk UDT Instance management screens and scripts that make life a little easier too. Hey, if you’re working with Siemens TIA, have you tried the on board OPC-UA? That way you can reference tags by symbol and not address and you can optimise blocks. ---
**Author:** ![zxcslo](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/zxcslo/32/61610_2.png) [@zxcslo](https://forum.inductiveautomation.com/u/zxcslo)\ **Post date:** [March 6, 2020, 8:28am UTC](https://forum.inductiveautomation.com/t/to-udt-or-not-to-udt-that-is-the-question/32703/22 "2020-03-06T08:28:24Z")
Yes, I’ve tried, but I wasn’t satisfied… When I exceed around 2000 tags, the communication with the onboard OPC-UA became unstable and every few seconds every tag had errors… Can you share this UDT Instance management screens and scripts of yours? ---
**Author:** ![ziad](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ziad/32/6841_2.png) [@ziad](https://forum.inductiveautomation.com/u/ziad)\ **Post date:** [May 1, 2020, 10:48am UTC](https://forum.inductiveautomation.com/t/to-udt-or-not-to-udt-that-is-the-question/32703/23 "2020-05-01T10:48:31Z")
> [@zxcslo](#): > > When I exceed around 2000 tags, the communication with the onboard OPC-UA became unstable and every few seconds every tag had errors... If you're using the Siemens OPC-UA, there is a setting that limits the number of subscribed tags. In Hardware configuration, go to OPC UA\>Server\>Options. The setting is called "Max. number of monitored items" You can put this up as high as 20,000. ![image](https://us1.discourse-cdn.com/inductiveautomation/original/2X/7/731af9aa17e94d24d4621ac8197b6ded24489137.png) [Previous page](https://forum.inductiveautomation.com/t/to-udt-or-not-to-udt-that-is-the-question/32703.md?page=1)