# The device connection overload is excessive **URL:** \ **Category:** Ignition\ **Tags:** ignition81\ **Created:** [November 30, 2023, 10:11am UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521 "2023-11-30T10:11:05Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![vincent.hu](https://avatars.discourse-cdn.com/v4/letter/v/5e9695/32.png) [@vincent.hu](https://forum.inductiveautomation.com/u/vincent.hu)\ **Post date:** [November 30, 2023, 10:11am UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/1 "2023-11-30T10:11:05Z")
In the project, I need to connect the new Siemens 1500plc to read and write data. In this process, I encountered some problems. I only added 372 points, but overload reached 161% and the writing delay reached 3129ms, which was the result after I increased the polling rate to 1200ms. Normally 372 points wouldn't be such a high overload, would it? What are the factors that affect overload? What should I do next? ![f2a97ae52ed6c1967e1367d286e5763](https://us1.discourse-cdn.com/inductiveautomation/original/3X/5/0/50d407bfd7b02f211e7321bf3758bd0d7851ccc7.jpeg) ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [November 30, 2023, 1:14pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/2 "2023-11-30T13:14:00Z")
Your 372 points are generating 65 separate requests, which indicates that the various points are scattered all over in your PLC. Combine as many points as possible in the PLC in just a few DB, with the points as close to consecutive as possible. This will dramatically improve how many points can be read per request, thereby reducing the number of requests needed. (Your mean response time looks terrible, by the way. Are you trying to make this connection from outside the plant?) ---
**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\ **Post date:** [November 30, 2023, 3:13pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/3 "2023-11-30T15:13:55Z")
> [@pturmel](#): > > Your 372 points are generating 65 separate requests, which indicates that the various points are scattered all over in your PLC. Yeah, or they're reading a bunch of Strings? All the other S7 datatypes are fairly standard/small, though you are also limited by a pretty small PDU size. The S7-1500 built in OPC UA server might actually perform in this case. ---
**Author:** ![Inken\_Kestler](https://avatars.discourse-cdn.com/v4/letter/i/bcef8e/32.png) [@Inken\_Kestler](https://forum.inductiveautomation.com/u/Inken_Kestler)\ **Post date:** [September 2, 2024, 8:08am UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/4 "2024-09-02T08:08:01Z")
Hi, I have similar problems. MY DBs I'm reading are not really small, but the issue is mainly caused by the strings. If I disable all of my strings, the number of requests will dicrease dramatically. @Kevin.Herron Is there any better way reading strings without such overload issues ? Inken ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [September 2, 2024, 1:07pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/5 "2024-09-02T13:07:43Z")
See Inken's full question and situation over here: > [@PLC Overload by strings](https://forum.inductiveautomation.com/t/plc-overload-by-strings/95250): > > Hi together, I have a Siemens S7-1500 and facing some overload issues. Within the plc I have several DBs with similar structure (including several strings) I want to read. But even if I enable only one DB I already se 160 requests: When I enable more than one DB the request number increases and the overload shows more than 100%. When I disable the strings within the DB the reqesut count is decreasing extremely. So I guess the strings are the reason for the high number of requests… Inken, see the "Keep it Tidy" section of [this forum's rules](https://forum.inductiveautomation.com/faq). ---
**Author:** ![Alaa\_Soulaiman](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/alaa_soulaiman/32/69782_2.png) [@Alaa\_Soulaiman](https://forum.inductiveautomation.com/u/Alaa_Soulaiman)\ **Post date:** [November 7, 2024, 1:11pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/7 "2024-11-07T13:11:43Z")
How can one reduce the count and % for Allen-Bradley? I am currently at 6500% with 214 request counts....Thanks ---
**Author:** ![bschroeder](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/bschroeder/32/13260_2.png) [@bschroeder](https://forum.inductiveautomation.com/u/bschroeder)\ **Post date:** [November 7, 2024, 1:18pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/8 "2024-11-07T13:18:25Z")
Are you reading entire structures from an API? How are your tags structured? What PLC? There is an incredible amount of factors that go into having efficient communication with RA PLCs. ---
**Author:** ![Alaa\_Soulaiman](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/alaa_soulaiman/32/69782_2.png) [@Alaa\_Soulaiman](https://forum.inductiveautomation.com/u/Alaa_Soulaiman)\ **Post date:** [November 7, 2024, 1:41pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/10 "2024-11-07T13:41:57Z")
1. Yes 2. They are DINT's strings and bools. 3. Control logix. I will see to fixing the reading of the structures. ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [November 7, 2024, 2:11pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/11 "2024-11-07T14:11:23Z")
> [@Alaa\_Soulaiman](#): > > reduce the count and % for Allen-Bradley? You have a lot of reading to do: > [@Ignition & Logix Best Practice Tips for better communications](https://forum.inductiveautomation.com/t/ignition-logix-best-practice-tips-for-better-communications/60386): > > Hi All, After a whole bunch of issues I have gone down the rabbit hole of what is wrong with our setup on site. I will preface this by saying I a relatively new to all of this.... so be gentle stuck_out_tongue Based on much reading(such wow) I believe I have a list of things our site could take away for a better system. Some of them are easy to implement, whilst some of them need... significant work to realize. Especially the AOI approach in point 5 expressionless Before going too far a… You probably have to make some changes in your PLC. However, if any of the tags you are currently pointing at are aliases into arrays or structures, change the Ignition OPC Item Path to point directly into the element of the array or structure. That's a big, easy win. ---
**Author:** ![Alaa\_Soulaiman](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/alaa_soulaiman/32/69782_2.png) [@Alaa\_Soulaiman](https://forum.inductiveautomation.com/u/Alaa_Soulaiman)\ **Post date:** [November 7, 2024, 6:43pm UTC](https://forum.inductiveautomation.com/t/the-device-connection-overload-is-excessive/82521/12 "2024-11-07T18:43:38Z")
I was able to reduce overload by increasing rate on tag group editor, and deleting a large amount of tags not needed, which included UDTs and arrays within the UDTs. I also increased the concurrent requests from default 2 on my Control Logix to 4 on the gateway device settings. Thanks everyone for the help!