Beckhoff EL72 1-901 Series, Manual

Page: 35 / 263

Basics communication
EL72x1-901x 35 Version: 1.9
3.6 Distributed Clock
The distributed clock represents a local clock in the EtherCAT slave controller (ESC) with the following
characteristics:
• Unit 1 ns
• Zero point 1.1.2000 00:00
• Size 64 bit (sufficient for the next 584 years; however, some EtherCAT slaves only offer 32-bit support,
i.e. the variable overflows after approx. 4.2 seconds)
• The EtherCAT master automatically synchronizes the local clock with the master clock in the EtherCAT
bus with a precision of < 100 ns.
For detailed information please refer to the EtherCAT system description .