4
Description of
functions
Introduction
The annunciator unit SACO 16D1 is a flexible
and versatile annunciator package comprising
16 input alarm channels. Its main purpose is to
supervise a given process and to call attention to
abnormal process conditions by the use of indi-
vidual visual LED indicators and a common
audible device. The annunciator system can also
be connected to an event recorder system, by
means of which printed records with channel
identification, date and time, are obtained when-
ever a change in the state of an alarm channel
occurs.
The basic functions of the annunciator unit are
illustrated in the block diagram below.
The alarm channel inputs are connected to the
field contacts. The field contacts, i.e. the output
contacts of the devices sensing the process con-
dition can be of the normally open (NO) or the
normally closed (NC) type.
The central unit continually compares incom-
ing channel information with previously stored
information. When a change of state has been
detected, the alarm channel is activated and if
the situation persists for a longer time than the
specified channel input delay time, the event
will be registered. The visual indicators and the
auxiliary output relays respond to the situation
according to the functional program they have
been given.
The annunciator unit can be acknowledged and
reset with a push-button on the front panel or by
means of external remote push-buttons.
The annunciator unit comprises an internal
event register. The unit is provided with a serial
communication interface and thus it can be
connected to a local data collector, e g a SRIO
500M/1000M, by means of a serial communi-
cation link. The information stored in the event
register of the annunciator unit can be read out
via the serial communication link.
Fig. 1. Block schematic diagram for the annunciator unit SACO 16D1.
Internal supply
SWIM 2A1
Alarm channels 1...16
1
2
16
Supply
1 2
Serial communication
SPA-buss
connection
Self-supervision
and audible
alarm output
Group reflash
outputs
1
2
Remote
reset/ackn.
48V
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