Mode of operation

Repeater functionality

The diagnostics repeater is integrated into the bus system as a RS 485 repeater, but it has its own PROFIBUS DP address:

• Expansion of extension in the bus system
• Regeneration of the signals in edge steepness, amplitude and time (re-timing)
• Isolates connected segments
• Configuration in STEP 7, COM PROFIBUS or also using a GSD file.

As of FW Version V2.0.0, the following additional functions will be supported:

• I&M functions according to PROFIBUS Guideline Order No. 3,502 in version V1.1, dated May 2003
• Time synchronization via S7 mechanisms
• DP cycle time measurement and statistics

Diagnostic functionality

Initiated by STEP 7, COM PROFIBUS or the user program (SIMATIC S7-1500 / S7-400 / S7-300), the diagnostics repeater identifies the topology of the connected segments and saves this information in the internal diagnostic memory.

If an error occurs, the repeater automatically transmits a standard diagnostic message to the bus master with the following information:

• Affected segment
• Error location (e.g. between station X and Y)
• Distance from stations X and Y as well as from the repeater in meters to the error location
• Type of error

The following errors are diagnosed:

• Break in signal lines A or B
• Short circuit of signal lines A or B on the shield
• Absent terminating resistors
• Unacceptable cascading depth (between any two nodes, no more than 9 repeaters be connected in series)
• Too many stations in a segment
• Station too far from the diagnostics repeater
• Faulty messages

Sporadic errors are also detected.

The error messages are displayed graphically in STEP 7 and COM PROFIBUS. They are completely integrated in the SIMATIC system diagnostics (e.g. overview diagnostics, "Report system error" function).

The display in STEP7 also includes a help text with troubleshooting measures. The help text is written in a way that does not require specific PROFIBUS expertise, so that the error can be quickly localized and removed.

Network topology and statistics display

You can view the topology graphically in Step 7 as of V5.2. The stations and the line lengths are shown in the topology display.

You can also view the bus system quality in the form of statistical information.

Print function

STEP 7 V53.3, SP 3 includes an improved print function. It allows you to preview on the screen and optimize the printout. For instance, you can hide certain details and print out an overview of the topology on DIN A4 or DIN A3 paper.

Configuring

The diagnostics repeater is configured as follows:

• TIA Portal V11.0 and higher
• STEP 7 V5.1 or higher, incl. Service Pack 2
• COM PROFIBUS V5.1, incl. Service Pack 2
• External tools: Use GSD file

The topology can be determined using external masters with the help of the COM PROFIBUS. The topology cannot be identified using an external configuration tool. However, if the topology is determined once using the COM PROFIBUS, error location information will also be displayed in the external configuration tool.