BECKHOFF EtherCAT Technology Section I - Manual (Page 71)

Distributed Clocks
Slave Controller – Technology I-51
9.1.2.2 Propagation Delay Measurement Example
The propagation delay between the local device and the Reference Clock device is calculated for the
network example shown in Figure 28. The example assumes that slave A is the Reference Clock. The
loops of slave D and F are closed internally. The wire delays are assumed to be symmetrical, and the
processing and forwarding delays are assumed to be identical for all ESCs.