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TimeHub 5500 User’s Guide
097-55501-01 Revision M – January 2009
Chapter 2 Engineering Ordering Information
NTP Server Card
An EC card inserted into the EC1 (leftmost) slot “prefers” to take its clock from
CLK1 (leftmost Clock card on the Master shelf). If it can obtain a valid link only by
using CLK2, the alarm LED lights.
An EC card inserted into the EC2 (rightmost) slot “prefers” to take its clock from
CLK2 (rightmost Clock card on the Master shelf). If it can obtain a valid link only
by using CLK1, the alarm LED lights.
The leftmost Clock card and leftmost EC card are a preferred pair while the
rightmost Clock card and rightmost EC card are a preferred pair.
NTP Server Card
This section describes the TimeHub NTP Server card (part number 090-55582-01).
It provides details on operation, configuration, alarms, events, and specifications.
Conceptually the TimeHub NTP Server card is another output card in the TimeHub
shelf, and it is managed like other TimeHub output cards.
diagram of the TimeHub shelf with a pair of NTP Server cards installed.
Figure 2-12. Block Diagram of NTP Server Cards in the TimeHub Shelf