RSView 32 problem

[vufu]

Nice to have friendly people around the world who can help you. This is my first question, and how I understand not the last one. Before I decided to ask, I read almost all topics in this forum related to my question, I'm sorry if I missed answer.
I'm not a big proffy in RSView32, but I can deal with basics.
We control our process with PLC5/60, we use PC Pentium4 (Windows XP), RSView32; RSLinx professional; DH+, to collect data and monitor process. Problem is that data on monitor are blinking, I tried to change drivers ( Direct Driver, OPC, DDE ) best result I've got with Direct Driver, but still data( pressure, temperature, flow, line speed...) are blinking, may be with less frequency. I checked all tags they are OK. Before we had Pentium2 233 ( Windows NT )same setup and everything ran normal, I heard somewhere, that RSView run not very well under XP, but on AB website I found that all problems were solved.
Thanks for any suggestions
I'm sorry if I'll don't answer same day,sometimes I'm busy, and no time to open internet
VUFU
Sorry for bad English,but this is my second language

[chavak]

Not sure this is correct or not,-
Try changing the forground/background scan time in RSView.

[RSVIEWRULZ]

You English is just fine!!!! Better then mine on a good day!

Chances are the Scan classes need to be set up differently.
(as stated by chavak)

First off, the best node that can be used for this communications is going to be “direct driver” This will give you the fastest connection speed.

With the Project manager open and the EDIT MODE tab clicked, double click “Scan class”

You will see the name of each class as A, B, C, D, E and so on. The foreground time is the time that the tag is scanned for updates in seconds, when displayed. The Background scan time is how often it scans when it is not displayed. The foreground scan also is used

If you want to display the Temps or do a Trend, you might want the scan time reduced considerably if it is a changing value. Such as .5 sec.

After you have come up with the scan times you think you need, you need to assign these to the appropriate tags.

So if you want a tag that displays on the screen to be constant as possible, you might want to set the scan class “B” to .5 seconds Foreground and the Back Ground to 2.0 seconds. Now go to the tag database, find the tag and change it to scan class “B”



The following is from the Rsview32 Help
Guidelines to set up scan times

·When you increase the scan rate you increase the load on the CPU, which can slow the system down. For this reason you have to set scan periods for optimal efficiency for your system. The optimum scan rate for a given system depends on factors such as the number of subsystems that are running and the CPU speed.

·Specify a frequent scan rate for tags representing fast-moving devices and a less frequent scan rate for tags representing devices that change less often.

This approach helps optimizes system performance, providing high-speed scanning where required and saving on system resources by using less frequent scanning where acceptable.

·Set the scan period to be shorter than the expected rate of change in the associated tags' data. For example, if you scan every five seconds for a change of state that might occur once an hour, the entire system is needlessly burdened. Conversely, if you scan too slowly, the system can't monitor value changes that might occur between scans.

·Set foreground scan periods to be shorter than or equal to background scan periods.

·A scan period of zero means scan as quickly as possible. You can set foreground scan periods to zero, but never set background scan periods to zero. For foreground periods, use zero sparingly because this setting can result in so much traffic that overall system communication slows down. RSView32 will also scan as quickly as possible if scan rates are configured to be faster than it can handle. For example, if the user configures 1000 tags at 0.1 seconds, no errors are generated and the tags are scanned as quickly as possible. There is no guarantee that the specified scan rate will be met.

[vufu]

Thank you for your reply, yes, problem was in scan classes, all my tags ( more than 2000 ) were assigned to one scan class (A), after separation everything looks much better. May be I have to setup separate scan classes with different foreground/background time for temperature, flow, pressure,speed, time.
Thank you
VUFU

[DaveMac]

VUFU - Don't make a mistake like I did and not change those scan times of tags that don't need it. As stated your system is under load. I added an event and it was doing some wild things at different times. After a week of looking turns out scan times was the fix. Pick your tags that can be slow and assign them and that makes the biggest difference ie; 500 or so slow tags moved to 10 sec from .5 sec cut my needs in half on a 1500 tag DB.

Good Luck!