4. DESIGN AND PRINCIPLES OF OPERATION
4.1 The principle of detector’s operation is based on the control of optical medium density.
4.2 The detector consists of the detector itself and the base. The optical system, the signal
processing electronic unit and LED control circuit are in the plastic housing of the detector. The
detector is connected to the base with a 4-contact joint.
4.3 If there is no smoke in the sensitive zone of the optical system, the detector connected to
the control panel shall be in standby mode, the red LED periodical flashing indicates about.
4.4 When smoke appears in the sensitive zone of the optical system, the electronic circuit
issues the alarm signal by intermittent change of internal resistance that leads to current growth in
alarm loop. The red LED switches on in alarm mode and is steadily lit.
4.5 The reset of detectors to the standby mode occurs when the mains supply switches off
for not less than 3 s with the following energizing.
5. PLACEMENT AND INSTALLATION
5.1 You should site detectors in places with the following conditions:
-minimal vibrations of constructions;
-minimal illumination intensity;
-maximum distance from sources of electrical-magnetic interferences (electric wiring etc.),
infra-red radiation (heat devices);
-elimination of water ingress on the case and penetration out of the base;
-no gas, steam, aerosol emission that can cause corrosion.
5.2 Detectors are connected to the loop with the help of bases. Bases should be secured onto the
detectors’ site of mounting using two Ø6x25 mm expansion bolts and two Ø3x30 mm self-tapping
screws. The center-to-center distance between mounting holes of the base is 70±0,2 mm.
5.3 It is possible to connect up to three 0,5 mm
2
wires to one screw joint of the base.
5.4 There is an auxiliary free contact (screw joint) “5” on the base. The contact is meant for
convenience of fitting EOL and limiting resistors. The view of the base appears in Figure 1.
5.5 The wiring diagram for detectors to control panels is shown in Figure 2- Figure 3.
6. PREPARATION FOR OPERATING AND
SEQUENCE OF OPERATIONS
6.1 Open the package after receiving detectors, check contents.
ATTENTION! If detectors were in below 0
o
C temperature conditions before opening
the package, allow them to acclimatize inside the structure for at least 4 hours.
6.2 Test detectors for proper operating.
6.2.1 Connect the detector to a DC power source of 20-30 V and the load current 50 mA
(“plus” connect to the contact “5”, between contacts “5” and “2”connect the 1 kOhm±5% current
limiting resistor, “minus” – to the contact “3”).
6.2.2 Switch on the mains supply and in not less than 10 s introduce into the test hole on the
detector’s cover (plastic or metal pin Ø1-1,2 mm, 4-5 mm long) and simultaneously switch the
stopwatch on.
6.2.3. When the LED is on, stop the stopwatch and determine the response time (lag) that
should be 10s.
6.3 The reset to standby mode should be made by turning off the mains supply for at least 3
s.
