janitza UMG 512-Pro, User Manual And Technical Data

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UMG 512-PRO
INFORMATION
· A Modbus address list including all the PTP parameters of your device can be found in the
download area at www.janitza.com.
· Specifications for PTP (Precision Time Protocol) can be found in IEEE Standard for a Precision
Clock Synchronization Protocol for Networked Measurement and Control Systems (IEEE Std.
1588-2008).
· The device supports PTP according to the default PTP profile Annex J IEEE 1588-2008 with the
profile ID 00-1B-19-00-01-00.
11.8.3 Example: PTP timing according to IEEE 1588-2008 and clock types
Ordinary clock
(OC) Simple clock (one port, measures one client) that is connected with a master as the slave
and synchronizes its time with the master.
Boundary clock
(BC) Clock that contains several “ordinary clocks” (several ports) and, as the master, synchro-
nizes several slaves with its time and transports this beyond a network boundary. The
“boundary clock” can also be connected to a master as a slave and synchronize its time
with the master.
Transparent clock
(TC) Clock that does not actively intervene in the time synchronization; it is more a hardware
item that transmits time synchronization data packets (e.g. a network switch). “Transparent
clocks” can also correct the time stamp within the data packet by the dwell time within the
hardware, if needed.
Grandmaster clock
(GC) The grandmaster clock is an “ordinary clock” that has access to GPS or another very
accurate time and provides this time for all subordinate nodes.