LN1000 IS Annunciator
23
SECTION 7 SEQUENCE TABLES
Example Sequence Tables
Each alarm channel can be configured to suit the operating sequence required, as listed in
the ISA publication "Annunciator sequences and specifications" S18.1 1979. Systems can be
configured with different features on different alarm ways.
Remember after changing a DIL switch setting it is essential that the power is turned off and
on again to register the new settings.
The following tables show the most commonly used examples.
ISA – M Manual Reset
PROCESS
SEQUENCE
LED
LCD
ABNORMAL
OR NORMAL
ALARM
FLASHING
(A)
SEQUENCE
PROCESS
OFF
LED
LCD
N
NORMAL
NORMAL
ACKNOWLEDGE
RESET
WHILE NORMAL
TO
ABNORMAL
LCD
LED
SEQUENCE
PROCESS
ABNORMAL
OR NORMAL
ON
ACKNOW
AUDIBLE
SILENT
AUDIBLE
AUDIBLE
N
AUDIBLE
SILENT
A
N
Sequence features
Acknowledge, reset and lamp test pushbuttons required
Alarm audible device
Lock-in of momentary alarms until acknowledged
The audible device is silenced and flashing stops when acknowledged
Manual reset of acknowledged alarms only after process conditions return to normal