Siemens Industry Online Support
Siemens AG
Entry type: Application example Entry ID: 21869196, Entry date: 06/25/2012

Determination of the PN/DP response time for typical configurations of IO controllers and DP slaves via IE/PB link or IWLAN/PB link.

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Many applications require a quick response time via the distributed inputs and outputs. Apart from the PROFIBUS DP, SIMATIC also uses the PROFINET IO for quick and efficient data exchange between distributed I/O and S7 stations. With PROFINET IO, the Industrial Ethernet technology has now been introduced to the field level.
Typical PROFINET IO configurations consist of one IO controller with several IO devices, where programming devices or operating devices (panels) are also used.

If existing DP masters are refitted to IO controllers, the resulting response time is especially important, since the net transition from Industrial Ethernet to PROFIBUS DP must be accomplished too.

  • How long does it take until a distributed output responds to a distributed input?
  • What fluctuations can occur?
  • To what extent does communication via PROFINET IO have an influence on the cycle time of the IO controller?
  • What updating time is to be expected?
  • What effects does the combination of the PROFINET IO with the PROFIBUS DP have?
  • What are the effects of connecting with the IWLAN/PB link?

The following screen shows the schematic layout of the measurement on a variant:

To answer the above questions, Industry Automation and Customer Services carried out extensive measurements on typical configurations with SIMATIC components, which provide planning certainty for your plants:

  • Various IO controllers communicate with up to 60 DP slaves.
  • Either a programming device or three operator panels are operated.
  • The IO controller runs with a typical user program. Typical configurations are loaded in the operator panels. In the programming device, the State function is active.

A simple user interface of a web application provides you with the results of the measurements.

Overview of the measured variables:

Measured variable


PN/DP response time Time from receipt of a process signal at the input of the ET200 to the activation of an output at the ET200.
Cycle time Time between two process image transfers in the IO controller.
Update time Time between two IO cycles of the IO controller.

Measurement was performed for some typical configurations. This does not mean that every possible configuration has been measured.

Outputs on the user interface
An interactive user interface enables you to quickly and easily enter your desired configuration.
The corresponding performance data is available by clicking the mouse.

Access to the performance data
Click the respective version to go to the web interface of the performance data.

Version Measuring time Components used Link
V 2.5 Nov 2006 Measured_Components_of_PNDP_ID12.pdf ( 44 KB )


V 2.0 May 2006 Measured_Components_of_PNDP_ID8.pdf ( 43 KB ) PNDP_ReaV2
V 1.0 Aug 2005 Measured_Components_of_PNDP_ID4.pdf ( 44 KB )


Last modification
Provision of all old measurements.

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