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Entry type: Application example Entry ID: 82203451, Entry date: 05/22/2018

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

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The PROFINET CPUs S7-300, S7-400, S7-1200, and S7-1500 can only be configured as NTP clients for time synchronization. With this STEP 7 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 S7-1200 CPU as SNTP server in an automation cell.

Figure 1

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.

V3.0.1 for TIA Portal V14 and higher
  Documentation (1,5 MB)
 Registrierung notwendig  Library "LSNTP" for TIA Portal V15 (535,5 KB)
 Registrierung notwendig  Library "LSNTP" for TIA Portal V14 (505,0 KB)
 Registrierung notwendig  Example project for TIA Portal V15 (1,2 MB)
 Registrierung notwendig  Example project for TIA Portal V14 (1,3 MB)

V2.0.0 for TIA Portal V13 SP1
  Documentation (1,1 MB)
 Registrierung notwendig  Library "LSNTP" for TIA Portal V13 SP1 (1,9 MB) 
 Registrierung notwendig  Example project for TIA Portal V13 SP1 (5,9 MB)

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

Last Changes

  • Upgrade to TIA Portal V15
  • Correction of the calculation of the reference timestamp if the date at "lastTimeSet" is before 1990

Additional Keywords

Time synchronization, time leveling, NTP server

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