MOUNTING AND INSTRUCTION MANUAL DTS 4148S.grandmaster

6.5.6 NTP slave clocks / time zone server

NTP slave clock line for operating slave clocks on the LAN (Ethernet). With this clock line, a world time function can be realized.

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1. Mode of clock line: 0 = off, 1 = Send NTP multicast, 2 = Send NTP multicast and time zone table, 3 = Send time zone table, 4 = Time zones on request, 5 (only for maintenance) = Send an empty time zone table and return to previous mode.

2. Multicast adress for NTP and time zone server: 239.192.54.x

Group address: x = 1-15 for MOBATIME devices, e.g. NCI, SEN 40.

3. Multicast port for Time zone server (enter an arbitrary value, empty is not allowed!

Value e.g.: 65534). The port is also needed for requesting time zone entries

(mode 4).

4. Poll-interval for NTP Multicast in 2^poll-values in seconds (range: 1 – 16).

E.g. poll-value = 2  interval: 2

2

= 4 sec., poll-value = 5  interval: 2

5

= 32 sec.

For redundant Multicast time servers see remark next page.

5. Packet time to Live (TTL) for NTP- and time-zone-Multicast-packets in hops.

(Number of Routers in a network to transfer the packets through; for simple network without routing, enter value "1", for 1 Router enter "2").

6. Repeat time to send time zone table: 10 – 86400 sec.

7. Delay time between the sending of the individual time zone entries (one entry per

Multicast packet) of the table: 1 – 60 sec.

8. Configuration of individual time zone entries. Displays menu “TIME ZONE TABLE“.

Notice:

Changes of multicast address, poll interval and TLL lead to a restart of the NTP server.

Notice:

For the operation of a multicast communication (NTP and Time Zone

Server) the configuration of a gateway is required (see chapter “6.5.22

Network”). The gateway can be set manually or by using DHCP.

If there’s no gateway available, it’s possiible to set the own IP as gateway.

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Notice: Redundant NTP multicast server:

If two NTP servers in the same network should send NTP with the same

Multicast IP address (redundancy), then the first time server has to be configured with a small pollinterval (e.g. 2  4 sec.) and second time server with a large pollinterval (min. 100 x larger, e.g. 9  512 seconds).

As long as the first time server is sending NTP Multicast packets, the packets from second time server are ignored. This configuration is needed, to reach a defined situation for the end devices (the DTS with the more frequently NTP send rate gets higher priority for time reception).

Time zone table for the NTP slave clock line:

Display of all time zone entries (15) of time zone servers for NTP slave clock lines.

Choose a zone number to change selected zone.

Time zone selection  see chapter “6.5.27 Time zone selection“.

The page can be exited with 99. Changes are first stored or reset on the overlying menu page.

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