Profinet update time and watchdog time

aand74

Member
Join Date
Dec 2005
Location
Deinze
Posts
131
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?
 
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.
 

Similar Topics

I want to establish a Profinet network in my production plant to connect multiple devices, including a PLC, HMI, and multiple Profinet-based...
Replies
19
Views
552
Hi, I have a customer with a S7300 from around 2013 which they link to approx 25 inverters, 3 DP to DP converters and 5 IM153 remote I/O units...
Replies
8
Views
287
Hi Guys, I am trying to establish communication over profinet between Siemens S7-1200 PLC as IO device and codesys plc as IO controller. But I am...
Replies
39
Views
2,055
Greetings! Facing a problem I've not seen before. GE CPE100 unit, LAN2 set up as ProfiNet. Multiple Turck TBEN-L4-16DIP modules, and a...
Replies
3
Views
191
Hello. I cannot change the SendClock settings for a PROFINET IO device. I need to slow down the CODESYS PROFINET IO controller. What am I doing...
Replies
0
Views
175
Back
Top Bottom