Bosch Analogue Addressable Smoke detector

Brand : Bosch

Model: FAP- 425-DO-R

Country of Origin: GERMANY

Features:

• Highly reliable and accurate thanks to Intelligent

Signal Processing (ISP)

• Earliest detection of lightest smoke with dual optical

Versions (Dual-Ray technology)

• Monitors environment for electromagnetic influence

For fast root-cause analysis

• Automatic and manual addressing

AVENAR detector 4000 is a new range of automatic fire

detectors featuring a superb accuracy and swiftness in

detection. The versions with two optical sensors

(dual‑optical) are able to detect the lightest smoke.

The range includes versions with rotaries, manually

and automatically addressable, and versions without

rotaries for automatic address setting.

Sensor technology and signal processing

The individual sensors can be configured manually, or

timer-based via the LSN network.

All sensor signals are analysed continuously by the

internal evaluation electronics (ISP - Intelligent Signal

Processing) and are linked with each other via an

inbuilt microprocessor. The link between the sensors

means that the combined detectors can also be used

where light smoke, steam or dust must be expected

during the course of normal operation.

Only if the signal combination corresponds to the

characteristics of the application site, selected during

the programming, the alarm is triggered automatically.

This results in less false alarms.

In addition, the time of the sensor signals on fire and

fault detection is analysed, which leads to high

detection reliability for each individual sensor.

In the case of the optical and chemical sensor, the

response threshold (drift compensation) is actively

adjusted. Manual or time-controlled switch-off of

individual sensors is required for adjustment to

extreme interference factors.

Optical sensor (smoke sensor)

The optical sensor uses the scattered-light method.

An LED transmits light to the measuring chamber,

where it is absorbed by the labyrinth structure. In the

event of a fire, smoke enters the measuring chamber

and the smoke particles scatter the light from the LED.

The amount of light hitting the photo diode is

converted into a proportional electrical signal.

The dual-optical versions use two optical sensors with

different wavelengths. The Dual-Ray technology works

with an infrared and a blue LED so that lightest smoke

is detected fast and reliably (TF1 and TF9 detection).

Thermal sensor (temperature sensor)

A thermistor in a resistance network is used as a

thermal sensor from which an analog-digital converter

measures the temperature-dependent voltage at

regular intervals.

Depending on the specified detector class, the

temperature sensor triggers the alarm status when the

maximum temperature of 54 °C or 69 °C is exceeded

(thermal maximum), or if the temperature rises by a

defined amount within a specified time (thermal

differential).

Further characteristics

• A red flashing LED visible 360° indicates the alarm.

• Connection to a remote indicator is possible.

• The strain relief for cables in false ceilings prevents

the cables from being unplugged accidentally from

the terminals after installation. The terminals for

cable cross-sections up to 2.5 mm2 are very easily

accessible.

• The detectors have a dust-repellent labyrinth and cap

construction. The chamber maid plug (an opening

with closing plug) on the bottom is used to clean the

optical chamber with compressed air (not required

for the heat detector).

• The detector bases no longer have to be directed due

to the centralized position of the individual display.

They also have a mechanical removal lock (can be

activated and deactivated).