Micropack FDS301 - Page 13

Information for wirin
g
in the 4-20mA mode listed in fi
g
ures 5 to 8 on
p
revious
p
a
g
e:
3 Pair Termination:
Fully functional detector with continuous video and 4-20mA alarm output.
Reversal of polarity across terminals 1 & 2 will enable Micropack RS485
communication.
2 Pair Termination:
4-20mA output only with reversal of polarity across terminals 1 & 2
enabling Micropack RS485 communication.
3 Wire Termination:
Retrofit a
pp
lication where onl
y
3 wires are available.
4 Pair Termination:
Fully functional detector with continuous video, 4-20mA alarm output and
connected Micropack RS485 communication.
Micro
p
ac
k
RS485 communication should
onl
y
be
accessed
b
y
trained
p
ersonnel.
Table 1: Current Level Out
p
ut Indicators –
Default Factor
y
V
alues
with a tolerance of +/- 1mA
Alarm Rela
y
Fi
g
ure 9: 4 Pair Termination with rela
y
A further feature of the FDS301 flame detector
when configured in 4-20mA mode is that an
alarm relay is available if required. The alarm
relay contact closes on alarm and can be
employed by connecting to terminals 3 and 13 of
the device.
FDS301 
Terminal


1 
2 
3 
4 
5 
 
6

 
VideoOutput
RS 485
7
8 
It is highly recommended to always connect
terminals 3 and 4 back to equipment room
marshalling cabinet with the use of a twisted pair
cable. This allow access to the RS485 from the
safe area.
9 
 
 
 
 
 
10
 
 
 
11
12
13
14 
 
micro
p
ack.co.uk
AlarmRelay  
Video+
 
Video ‐‐‐  
24Vdc
 
0Vdc

AlarmRela
y
Signal  
Current Output Event
0mA Power/Detector Fault
2mA Optical Fault
5mA Healthy
18mA Alarm
21mA Over-range
FDS301 Flame Detector FDS301 Safety and Technical Manual
13
Ref: 2200.5009 Rev: 2.3 ECN 4434