Siemens Plant Central Clock TC100 - Manual (Page 79)

Parameter assignment
9-7  © Siemens AG 2010 All Rights Reserved
SICLOCK ® TC100 Operating Instructions
9.2 Connecting time receivers
The following options are available for connecting the time receivers::
• Ethernet connection via NTP Server
• Ethernet connection via SIMATIC Verfahren
The following sections describe the parameter assignment options.
9.2.1 NTP server service
An NTP server is available at the Ethernet port. The NTP server supports the
modes Any/unicast and Multicast according to RFC2030.
Any / unicast (standard mode)
This mode is used by, e.g., PCs.
You activate the NTP server in Any/unicast mode with the parameter entry
/NTP Server/NTP Server/Operation (0.16.01) = "On". The settings "Off" and "Only
when synchronized" are also available as options.
The setting "Only when synchronized" enables conditional operation. The server
service is only active when the device is externally synchronized.
Multicast
This mode has to be set explicitly for each subnet.
You can set Multicast mode for up to four subnets with the parameter
/NTP Server/Multicast[4]/Multicast[x]/Mode (0.16.02).
You define the Multicast IP address that will be used with the parameter entry
"Multicast address", e.g. 192.168.2.255.
Setting options for parameter entry mode:
• Off
• 10s – Standard mode, that is the coded time is time-zone independent
• 60s – Standard mode, that is the coded time is time-zone independent
• 10s with local time – for receivers without their own calendar
• 60s with local time – for receivers without their own calendar
You define the Multicast IP address that will be used with the parameter entry
"Multicast address".