Lucent Technologies SLC-2000 Access System Central Office Terminal, Инструкция по сборке

Страница: 233 / 284

363-208-010
Applications
Issue 5 May 1997
A-17
RT Input Alarms Applications
General
The SLC-2000 system provides a set of user-definable miscellaneous discrete
environmental alarms and controls to allow monitoring and control of collocated
equipment at a remote site. See Figure A-7 for the RT input alarm cabling and
typical alarm cross connections.
Fifteen miscellaneous discrete alarm/status points monitor environmental
conditions at remote terminal sites. These include such conditions as
open door
and high temperature. Contact closures to ground activate the first fourteen
points. The fifteenth point monitors the remote structure power and fan apparatus
(for example, DC power shelf failure). A -48 volt DC input activates this point.
Four control points control equipment, such as pumps and generators, at the
remote terminal site. When activated, the control points provide a contact closure
between the control point output and ground.
The SLC-2000 RT provides the following alarms, described in the paragraphs
below, in addition to the miscellaneous discrete inputs mentioned above:
■
Power Minor (PMN)
■
External Minor (MN)
■
External Major (MJ)
Power Minor Alarm
This alarm is used to detect the loss of commercial ac power at the RT and is not
considered service affecting when the RT power system has battery back-up. This
input expects a -48 VDC through a closure to activate the alarm and the no alarm
state is an open circuit.
Minor Alarms
Minor alarms are classified as not service affecting and are used to detect the
failure of a single rectifier in the power system, a single ringing generator in a
protected ringing system, or a fan failure. This input expects a -48 VDC through a
closure to activate the alarm and the no alarm state is an open circuit.