You are not registered yet. Please click here to register!


 
 
plc storereviewsdownloads
This board is for PLC Related Q&A ONLY. Please DON'T use it for advertising, etc.
 
Try our online PLC Simulator- FREE.  Click here now to try it.

---------->>>>>Get FREE PLC Programming Tips

New Here? Please read this important info!!!


Go Back   PLCS.net - Interactive Q & A > PLCS.net - Interactive Q & A > LIVE PLC Questions And Answers

PLC training tools sale

Reply
 
Thread Tools Display Modes
Old December 3rd, 2017, 03:24 PM   #1
aand74
Member
Belgium

aand74 is offline
 
Join Date: Dec 2005
Location: Deinze
Posts: 62
Profinet update time and watchdog time

We have several Siemens drives (CU320-2 controllers) on Profinet.
The Plc is a Siemens 416 PN cpu.
What could be advised to set the Profinet update time and watchdog time of the CU320-2 modules to?
I should want to set it as fast as possible, but don't want any communication problems on the other hand.
Is there a way to see the result of my settings on f.I. the load on the network?
When will I know that my settings are critical?
Are there general rules that provide concrete setting times for update and watchdog?
  Reply With Quote
Old December 5th, 2017, 02:31 AM   #2
aand74
Member
Belgium

aand74 is offline
 
Join Date: Dec 2005
Location: Deinze
Posts: 62
No idea's?
  Reply With Quote
Old December 5th, 2017, 07:57 AM   #3
mk42
Member
United States

mk42 is offline
 
Join Date: Jun 2013
Location: MI
Posts: 1,572
In general, if you let Step 7 select the update rates automatically (the default setting), you'll get a system that will work (with a fair amount of bandwidth left over for other stuff) but is still relatively fast. Some PN devices require slower update rates for that device, but you can do that on a case by case basis. I should think that you would be able to communicate with several CU320s at 1ms without any difficulty.

One question you may need to ask yourself is if you need IRT, or just regular RT PN comms. Are you controlling position loops in the PLC, or are the loops in the drive (typical speed control or EPOS).

The PN watchdog is traditionally 3x the PN update rate. The only time I've seen this changed is when you're using MRP, then you want the watchdog time to be longer than the ring reconfiguration time to avoid errors.

If you're talking about the failsafe watchdog, then that is entirely dependant upon your process and risk assessment.

In TIA Portal, one of the HW parameters is a calculated number of what % of the bandwidth is expected to be utilized for PNIO. I'm not aware of a similar feature in Simatic Manager.
  Reply With Quote
Reply
Jump to Live PLC Question and Answer Forum

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Topics
Thread Thread Starter Forum Replies Last Post
How do i set watchdog in codesys? kidi3 LIVE PLC Questions And Answers 14 November 17th, 2016 06:28 AM
ABB PLC watchdog timer owend LIVE PLC Questions And Answers 0 July 16th, 2013 12:13 AM
Slc 500 watch dog time and PID loop update time wilsonzhu LIVE PLC Questions And Answers 2 November 14th, 2008 11:33 AM
SLC5/04 First scan 993ms every time??? OkiePC LIVE PLC Questions And Answers 14 July 31st, 2007 11:07 PM
RSLogix500 Max san display update detail? OkiePC LIVE PLC Questions And Answers 2 July 30th, 2007 02:07 PM


All times are GMT -5. The time now is 06:22 AM.


.