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097-55501-01 Revision M – January 2009
TimeHub 5500 User’s Guide 125
Chapter 3 Installing the TimeHub 5500
Installing the Cover
Connecting External Alarms
Connect the external alarm inputs (customer-configured alarm inputs) to RACK
ALM INPUTS wire-wrap pins 1 through 10 on the Input/Alarm Connector module.
See
for the location of the pins.
The external alarm inputs allow the TimeHub 5500 to accept alarms from external
equipment. When an alarm is accepted:
an alarm LED lights in the “system” row on the Management card
the appropriate alarm output wire-wrap pins (AUD and VIS) activate on the Alarm
Connector card
an automatic message appears on the Local and LAN communications ports
(see
, on page 29), notifying a remote management system of
the external alarm condition.
There are two types of external alarm inputs: contact closure only and universal.
Contact Closure Only External Alarms
These six sets of alarm inputs (5-10) operate from any relay contact closure.
Severity levels associated with these alarm inputs are:
MAJOR: inputs 5 and 6
MINOR: inputs 7-10
Universal External Alarms
These four sets of alarms operate from any relay contact closure. They are also
capable of accepting alarms produced by a source transition to and from –48 V.
Transition from –48 V to 0 generates an alarm; transition from 0 to –48 V clears the
alarm. Severity levels for the universal alarms are:
MAJOR: inputs 1, 2
MINOR: inputs 3, 4
GPS Input
The GPS connector is reserved for future use.
Installing the Cover
Fit the plastic cover over the rear of the shelf after you make all connections. Use
the captive screws to attach it to each corner of the shelf.