PTP 1588 Synchronization Time Difference Between PXIe Systems and Server PC

Updated Apr 7, 2023

Reported In


  • PCI-1588
  • PXI-6683


  • Measurement & Automation Explorer (MAX)

Issue Details

I am trying to synchronize my PXI-6683H Synchronization module to a PCI-1588 module implemented in my server. However, the system time on the PXI cards appears to be around 37 seconds slower than the system time on the PC server. How can I solve this?


The 37 seconds is the current offset between UTC and TAI timescales. The system time on the server PC is set on the UTC timescale, whereas the PTP 1588 protocol usually uses the TAI timescale. To correct this offset, follow the Configuring IEEE 1588 synchronisation with the NI PXI-668x Timing and synchronisation module tutorial.

Please refer to UTC, TAI, and GPS Time Scale for NI Synchronization Interfaces for further information.

Additional Information

There are two PTP implementation methods: Hardware Timestamping and Software Timestamping. If you are using Hardware Timestamping, please make sure you disable the Software 1588 Time Protocol (PTP) in the Time Settings of the device in NI Measurement Automation Explorer (NI MAX). It will avoid conflicts in the synchronization.