Pilz PSSnet SHL 8T MRP - Manual (Page 96)

Synchronizing the system time in the
network
PSSnet SHL - Basic Configuration
Pilz GmbH & Co. KG, Felix- Wankel Str. 2, 73760 Ostfildern
7.3 Precision Time Protocol
97
7.3 Precision Time Protocol
7.3.1 Description of PTP functions
Precise time management is required for running time-critical applications via
a LAN.
The IEEE 1588 standard with the Precision Time Protocol (PTP) describes a
procedure that assumes one clock is the most accurate and thus enables
precise synchronization of all clocks in an LAN.
This procedure enable the synchronization of the clocks involved to an accu-
racy of a few 100 ns. The synchronization messages have virtually no effect
on the network load. PTP uses Multicast communication.
Factors influencing precision are:
X Accuracy of the reference clock IEEE 1588 classifies clocks according to
their accuracy. An algorithm that measures the accuracy of the clocks
available in the network specifies the most accurate clock as the "Grand-
master" clock.