Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

User-defined web page too sloooow...

Created by: Erik Sparre at: 3/16/2012 2:23 PM (8 Replies)

Rating (0)

Thanks 1

9 Entries

3/16/2012 2:23 PM	Rate (0)
Erik Sparre Posts: 10 Rating: (3)	Hi, I have a simple user-defined web page in my S7-1200 system. The problem is that it takes ages to reload. About 25 seconds for 28 values! Fewer values takes less time, but is still slow. There is very little else on the page, certainly no graphics or CSS, nor script, just plain text. Most of the values a of type REAL. Are these times typical? Can I do anything to speed things up without reducing the number of values on the page? Accessing the standard web page is fast, so I don't think there is anything wrong with my general system setup. Thanks
Erik Sparre Posts: 10 Rating: (3)
Suggestion To thank Quote Answer

3/16/2012 3:11 PM	Rate (0)
0_Einstein Diamond Expert Joined: 7/7/2010 Last visit: 1/24/2025 Posts: 15556 Rating: (2467)	If the web server is more important than solving logic scan time, you can divert system resources to overhead services like the web server in the PLC configuration. The default is to allocate up to 20% for that task. If you bump it to 50%, it might help. However, if you are displaying 28 values in this tiny plc's web server, you might want to look for another solution. Maybe create a few pages with smaller amount of values per page and group the data on different pages. This should speed things up as well.
	science guy
Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users Erik Sparre

3/16/2012 4:41 PM	Rate (0)
Erik Sparre Posts: 10 Rating: (3)	Thanks. I wasn't aware that the Communications load setting influenced the web server response time. Changing it from 20% to 50% speeded things up significantly. Around 6 seconds instead, without too much effect on OB1 cycle time. Still not fast, but as you say, it is a tiny PLC. Maybe it is faster to convert values into strings in the PLC code, concatenate them, and finally display those strings in a web page. I'll consider it.
Erik Sparre Posts: 10 Rating: (3)
Suggestion To thank Quote Answer

6/12/2012 5:13 AM	Rate (0)
Morgan_Kane Posts: 2 Rating: (0)	Hi, with many variables on the web page - say like 10 or more - updating rate could be quite slow. I have found couple of things how you can speed up things. 1. Raise communication load percentage. 2. Decrease refresh time interval from default 10s to less. This has to be done on web page. 3. And the last one, but the most important thing. S7-1200 takes a lot of time to gather variables what are going to be shown on the web page if they are not gathered in to same data block. So copy all the variables etc. in to the same data block and then use these on the web page. If you dont do this, update interval could be like one second per each variable. I did create one data block only for the web page things.I did have update interval of 50 seconds and after these actions it is approx. six seconds or so.
Morgan_Kane Posts: 2 Rating: (0)
Suggestion To thank Quote Answer

7/27/2012 11:33 AM	Rate (0)
joaofaro Posts: 14 Rating: (0)	Hello. I'm having a similar problem but in my case sometimes I can't even access Introduction page (default page of the plc). Where do you change this settings? And in your third advice, you create a block and call it in the main block (OB1)? And what you do inside? Your operations with variables or you just move values to and from the variables you use in web page? My web page variables are the same I use in mathematical operations inside a lot of blocks, is that a problem? Thank you for the help!
joaofaro Posts: 14 Rating: (0)
Suggestion To thank Quote Answer

7/27/2012 12:17 PM	Rate (0)
joaofaro Posts: 14 Rating: (0)	Solved! I change two things: Increase communication load to 50% and uncheck https access. Now everything is working, thank you
joaofaro Posts: 14 Rating: (0)
Suggestion To thank Quote Answer

8/16/2012 2:38 AM	Rate (0)
luki luki Posts: 3 Rating: (0)	Hello, Can you tell how muchtime it takesto reload the page now ? Regards, Luki
luki luki Posts: 3 Rating: (0)
Suggestion To thank Quote Answer

8/16/2012 8:21 AM	Rate (0)
Erik Sparre Posts: 10 Rating: (3)	The simplest web page I could create had one variable and a few characters plus the <body> tag. It takes around one second (eyeballed) to reload this page when viewed in a PC browser. I'm using a S7-1214C CPU at 20% communication load. More variables means longer time, somewhere around an extra second or so per variable (at 20% load). All variables are from the same datablock in my case. Extra static text seems to have limited influence on the time.
Erik Sparre Posts: 10 Rating: (3)
Suggestion To thank Quote Answer

8/27/2012 8:33 AM	Rate (0)
Morgan_Kane Posts: 2 Rating: (0)	joaofaro Hello. I'm having a similar problem but in my case sometimes I can't even access Introduction page (default page of the plc). Where do you change this settings? And in your third advice, you create a block and call it in the main block (OB1)? And what you do inside? Your operations with variables or you just move values to and from the variables you use in web page? My web page variables are the same I use in mathematical operations inside a lot of blocks, is that a problem? Thank you for the help! Sorry for the late answer and I notice you did solve the problem, but anyway. Create a new data block to use only with the web page. Copy all the variables to this data block which you need to show on the web page. And when you are creating the web page, read variables only from this "dedicated" data block. Then plc can find all the needed information from the same place (data block), not to need "wander" through all the blocks etc. to find out correct variables. If you read variables only from the OB1 etc., without using dedicated data block for the web pages, things gets slow. I hope this helps.
Morgan_Kane Posts: 2 Rating: (0)
Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on