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Entry type: Application example Entry ID: 109760217, Entry date: 08/16/2019

Function blocks and faceplates for evaluation of the diagnostic interface "COM" and visualization of the device data

  • Entry
  • Associated product(s)
The SITOP PSU6200 power supply has a diagnostic interface "COM" whose signal can be evaluated via a digital input in a higher-level controller, e.g. S7-1200 CPU, S7-1500 CPU and S7-300 CPU / S7-400 CPU.

The diagnostic interface "COM" of the PSU6200 provides a signal that transmits the following device data as a Manchester code:

  • Voltage and current values
  • Nominal data
  • Device information
  • Temperature and operating hours

The following library provides function blocks for SIMATIC S7-1200, S7-1500, S7-300, S7-400 and faceplates for SIMATIC Comfort Panels. The function blocks enable you to read in and evaluate the signal of the diagnostic interface "COM" via a digital input at the S7-CPU. You can use the faceplates to clearly display the device data on an HMI control panel.


  • The library blocks for SIMATIC S7-1500 can also be used in an ET 200SP CPU and ET 200pro CPU.
  • The library blocks for SIMATIC S7-300 can also used in an ET 200S CPU and ET 200pro CPU.

The following image shows the graphic representation of the solution.

Fig. 1

1Power supply
2CPU with function block (FB)
3Digital input module (DI) 
4diagnostic interface "COM" 
5Output 24 V DC 
6Input 230 V AC 

Table 1

  Documentation Library "LPSU6200_V15.0-0_V1-1-0" (3,2 MB)
 Registrierung notwendig  Library for STEP 7 V15 (1,6 MB)

Last Changes  
Set and display status and default values in case of communication with diagnostic interface "COM" is not active.

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