Version 03
– 30.10.2019
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2. SFCP Rail Features
2.1. General
Dual Linear Heat Sensors up to 50 meter or conventional detectors can be used. Each are continuously
monitored for alarms, open and short circuit. LED flash codes indicate the location of an alarm or fault
condition.
The SFCP Rail has an intemal alarm sounder and an output to drive additional external audible alarm units
up to 2Amps. Also a Voltage Free Contact (1/FC), switched in case of fire, e.g. for fuel shutoff, engine/fan
shutdown etc.
2.2. Zones
The SFCP Rail is equipped with two conventional detection lines. The monitored inputs are
continuously scanned for fire or fault detection. The lines are set to the following values:
RESISTANCE of less than 190 Ohm:
FAULT
RESISTANCE of more than 190 Ohm and less than 1k2 Ohm:
FIRE
RESISTANCE of more than 10k Ohm and less than 12k / 27k Ohm: NORMAL
<10k Ohm or >12k Ohm.
– for 1 fire switches connected on one zone
<10k Ohm or >27k Ohm.
– for 2 fire switches connected in parallel on one zone
RESISTANCE of more than 27k Ohm:
FAULT
Note: When a low resistance (lass than 190 Ohms) linear heat cable is used, a 1k Ohms resistor
must be installed in series at the beginning of the line and one of the wires. Otherwise the
wires of a convetional point detector or a linear heat cable which melt together will give a fault
instead of a fire alarm.
The SFCP Rail zones use dedicated logics to manage the above-stated resistance levels, together with the
use of ADC inputs. The zone circuits output the input voltage (-0.6 volt, power multiplex spec.), with a current
fuse-limited at 50 mA.
The detector zone circuit will be reset upon initialization (ground connection will be intermittent during
led-test). Resistor levels are depending on the input voltage; therefore high fluctuations on the input
voltage of the SFCP Rail should be avoided by using screened cable.
The commissioner should ensure to be using detectors with corresponding specifications and the
correct input voltage for the SFCP Rail. The maximum amount of detectors in 1 zone is determined by
the voltage/amperage usage of the detectors and the input voltage. Devices which are supported by
the SFCP Rail are described in Appendix 2 of the manual.
Every detector zone needs a 10k Ohm resistor as End-Of-Line (EOL) resistor, even when the input(s)
will not be used. This to prevent a detection fault on the input(s).
