LN1000 IS Annunciator
13
Programmable Features
First up grouping
Each channel may be internally set by DIL switches
into 1 of 7 first-up groups or no group at all
Alarm sequence selection
ISA sequences A, M, R, F1A, F2M and F3A set by
DIL
switches
Field contact configuration
Selectable N/O or N/C operation per channel by
DIL
switches
Input delay
To avoid false alarms due to momentary abnormal
field contacts, such as with surging liquids in tanks,
a delay can be activated using DIL switches. The
delay time can be set by potentiometer between
four and 30 seconds. When enabled, the
annunciator will display an alarm if the field
contacts remain abnormal for greater than the
delay
time.
LN1000-SC Sequence Card
Input
Power
Supplied from IS isolator sited in the safe area
Outputs
Ext. Sound
Low level DC signal follows audible on ISA
sequence. May be used for switching DAA149 or
DAD149
IS
relays
B1
This output is configurable for both polarity and
function. The function can be of two types either
following the alarm logic or the alarm contacts.
Low level DC output
Configurable:
(a)
Active
low
(b)
Active
high
and
configurable:
(a) Active whilst any channel is in alarm state
(b) Active whilst any field contact in the "Field
Contact Group" is abnormal. Channels are
selected to be in the "Field Contact Group"
by DIL switches on the Alarm Card
B2
1 sec low pulse on new alarm
Used as a reflash signal to indicate to external
equipment that another alarm has occurred.
