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097-55501-01 Revision M – January 2009
TimeHub 5500 User’s Guide
45
Chapter 1 Description
TimeScan THC Software
Output Driver Card Redundancy
Each Output Driver card in an Expansion shelf slot-pair (“A”, “B”, …, “H”) receives
clocking information from the Clock card(s) installed in the Master shelf. If both
Clock cards are installed in the Master shelf, then each Output card receives clocks
from each, with preference given to the active Clock (as indicated by the Active LED
on the Clock card). Only one Output card per letter group is needed to create output
signals. Adding a second Output card to the letter group provides protection if either
Output card fails.
Communicating With the Expansion Shelf
The TimeHub 5500 Master shelf automatically attempts to communicate with the
EC card(s) in an Expansion shelf. When they respond, the Master shelf sets the TL1
keyword ECLKEXP for the cards to Y. The Master shelf then reports alarms or
events related to that Expansion shelf. If no EC cards are present, the ECLKEXP
remains at the default value of N. When ECLKEXP is N, the TimeHub 5500 Master
shelf does not expect communication from an EC card and no Expansion
shelf-related events are reported. This keyword is described in the
TL1 Reference
Guide.
If one of the EC cards is removed, an event (keyword EXCLKGONE) is reported
indicating that this card is missing. When the card is reinstalled, the event clears.
If you permanently remove an Expansion shelf from a TimeHub 5500 system,
manually set the value of ECLKEXP for the targeted EC card(s) to N. Any events
associated with the EC card will be cleared.
TimeScan THC Software
The TimeHub 5500 is delivered with a software application called TimeScan THC.
This application is a craft graphical user interface (GUI) that provides a point-and-
click interface for configuring and maintaining the TimeHub 5500.
contains procedures that use TimeHub THC. Use the
built-in Help system in TimeHub THC to answer questions regarding its use.