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Entry type: Application example Entry ID: 82203451, Entry date: 08/15/2019

Library for SNTP Server Functionality in SIMATIC S7 CPUs (LSNTP)

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The PROFINET CPUs of the automation systems SIMATIC S7-1200/1500 and S7-300/400 and WinAC RTX can only be configured as NTP clients for time synchronization. With this library you can turn a SIMATIC S7 CPU into an SNTP server and thus realize a simple time synchronization of automation cells.

In this entry we provide you with library blocks for all current SIMATIC S7 CPUs, which map the functionality of an SNTP server.
The following sample configuration shows a possible use, for example, of an S7-1500 CPU as SNTP server in an automation cell.

The LSNTP_Server function block provides the following functions:

  • Receipt and analysis of an NTP request from a client.
  • Creation and sending of an SNTP message to the requesting client.

For S7-1200 the library is valid for CPU firmware versions up to 3.x and 4.1.3 and higher.

TIA Portal V15.1
  Documentation (1,3 MB)
 Registrierung notwendig  Library LSNTP V3.0.2 for TIA Portal V15.1 (614,1 KB)

STEP 7 V5.5
  Documentation (1,0 MB)
 Registrierung notwendig  Library V1.0.0 for STEP 7 V5.5 (37,7 KB)

Last Changes

Replaced DCF77 with generic NTP server in overview graphic

Additional Keywords
Time synchronization, time leveling, NTP server

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