Nexus 21 A1557 User Manual
Page 5
Document Ref: Nex8inst.doc/Rev0 09.07.00
Page 5 of 30
Originator MC Checked by AC__
A1557 Field Terminal List [Listed along the top edge of the PCB from left to right]
Terminal Ident.
Function
Terminal Ident.
Function
Aux Fire NO 1
Fire relay normally open 1
Alarm 1
+
Sounder circuit 1 + [Active polarity]
NC1
Fire relay normally closed 1
-
Sounder circuit 1 - [Active polarity]
P1
Fire relay pole 1
Alarm 2
+
Sounder circuit 2 + [Active polarity]
NO 2
Fire relay normally open 2
-
Sounder circuit 2 - [Active polarity]
NC2
Fire relay normally closed 2 Network
NO +
Panel network out +
P2
Fire relay pole 2
NO-
Panel network out -
Aux Flt
P
Fault relay pole
NI +
Panel network in +
NO
Fault relay normally open
NI -
Panel network in -
NC
Fault relay normally closed
Loop 1
LO+
Loop 1 out +
Aux
24V
Aux DC supply [24V]
LO-
Loop 1 out -
0V
Aux DC supply [0V]
LI+
Loop 1 in +
I/O
MX+
Local I/O expansion port +
LI-
Loop 1 in -
MX-
Local I/O expansion port -
Loop 2
LO+
Loop 2 out +
Repeater RO +
Repeater out +
LO-
Loop 2 out -
RO -
Repeater out -
LI+
Loop 2 in +
RI +
Repeater in +
LI-
Loop 2 in -
RO -
Repeater in -
Remote
Inputs
SAL Silence
alarms
RST
Reset
EVC
Evacuate
SBZ
Silence
buzzer
COV
Class
change
alarm
FLT
Fault
1.1.6 Power
Supply
Illustration
12V
+
12V
+