Heat Fire Detection Using Barometer Linear heat detector TRANSAFE ADW 511 A

With intelligent signal evaluation

• Optimal response behaviour in every application
• Resistant to external influences
• Programmable pre-alarm
• Low maintenance expenditure thanks to fully-automatic testing device

Fires and explosions cause sharp increases in ambient temperatures: the warmed air expands. Securiton used this simple physical principle in its development of the SecuriSens®ADW heat detector. The device quickly and reliably detects even the slightest increase in temperature, and is indispensable in harsh environments - those involving corrosive gases, extreme humidity, high temperatures or contaminated air.
Installing SecuriSens®ADW can protect lives prevent damage and reduce insurance liabilities.

Effective fire protection thanks to air and high-tech
The SecuriSens®ADW is a linear heat detector. Sensor tubing, made of copper and extending to a distance of over 100 metres, contains trapped air that monitors the ambient temperature. An electronic pressure transducer at one end of the tubing detects a rise in the internal air pressure signalling higher temperatures. Connected via a serial interface, a computer in the evaluating processor unit continually analyses these air pressure values and immediately triggers an alarm if a defined threshold is exceeded. The system leaves nothing to chance: a monitoring motor with a pressurising pump generates always the same amount of excess pressure within the sensor tubing at regular intervals. If the measured pressure increase deviates from the programmed nominal value, the computer immediately reports a fault. The SecuriSens®ADW heat detector always plays it safe.
Technical Data

The benefits of SecuriSens® ADW:
100% monitoring coverage - even over great distances Resistant to harsh Environmental conditions Low maintenance Exhibits optimal Response behaviour with heat differential and maximum temperature evaluation whatever the application Programmable preliminary alarm Response Behaviour compliant to EN 54-5 A1 VdS- and ULcertified

Features
Principle: Linear rate-of-rise temperature detector with fully electronic measuring principle Response behaviour: Programmable within wide limits SENSTUBE sensor tube: Copper tube, 5 mm external diameter, SERTO screw fittings

 How Does It Work
The Transafe ADW 511 A heat detector utilizes the physical law of the change in volume of gases with temperature changes in the copper sensor tube SENSTUBE. A fully electronic pressure transducer measures the absolute pressure in the sensor tube. By intelligent, application-specific combination of the measured value, the response behaviour of the detector can be adjusted precisely to the detection requirements. A test motor with pressure pump generates an intentional, exactly defined excess pressure in the sensor tube at regular intervals. If the measured value of the pressure sensor does not correspond to the required value, for example due to a leak or compression of the tube, a fault indication occurs.

Application
Thanks to its robust construction, the new ADW 511 A is suitable for fire detection in extreme areas where conventional fire detectors are useless, Aggressive ambient conditions, extreme temperatures, such as in tunnels, in explosion areas and in other industrial applications, therefore represent the preferred field of application.
SecuriSens®ADW provides optimal safety in:
Multistorey and underground car parks Cable and transport ducts Gas and district-heating circuits Chemical production plants Manufacturing facilities and warehouses Conveyor systems, logistics and distribution Centres Storage tank installations Road, railway and metro/subway tunnels

Fire Protection in Road Tunnels
Great Fire Hazards
Traffic accidents in which escaping fuel and vehicles catch fire cannot be ruled out in road tunnels. However, the consequences are far more devastating than in the case of accidents in the open air. Within a very short time, the tunnel is completely filled with smoke. Following vehicles - up to two cars per second - drive into the scene of the accident causing a traffic jam. Smoke, heat, carbon monoxide, carbon dioxide and lack of oxygen are a direct threat to the lives of the people caught up in the jam. However, by means of an efficient tunnel fire detection system and further safety precautions (e.g. closing the tunnel entrances) it is for the most part possible to prevent a catastrophe.

Automatic testing
- All pneumatic and electrical components are checked periodically every couple of hours. As a result, maintenance works are reduced to a minimum. In addition, road traffic is not impeded by inspection works.
- Minimum structural height, therefore no risk of damage to the sensor tube
Each evaluation unit forms one detector group and is connected to the fire incident control unit accordingly. As a rule, in the case of an incident, the video monitor cameras for the section concerned are switched on, the traffic lights at the tunnel entrances are turned to red and ventilation is increased. The sensor tube length of 150m is an optimum compromise between monitoring length and the accuracy of fire detection. In the case of greater lengths, there is a risk that in the event of a system failure, too large stretches of road would be without a monitor.

Insensitive to external influences
Continuous monitoring of the entire length of the tunnel thanks to the linear arrangement of the TRANSAFE ADW 511 at the centre of the tunnel roof. In this manner, optimum response is achieved at any scene of a fire regardless of the function and system of the ventilation plant (transverse or longitudinal ventilation). Sensitivity variable for ideal adjustment to the ambient conditions. As a result, practically no false alarms with simultaneous optimum response sensitivity. Insensitive to ambient influences (temperature fluctuations, e.g. through exhaust fumes, pressure fluctuations, change in ventilation conditions, etc.). Insensitive to a chemically aggressive, dusty and moist environment during cleaning works, or by flapping truck tarpaulins and loosely laden items on vehicles passing through.

An above average large number of false alarms
Above average large false alarm Rae in car parks and underground garages from automatic fire detectors (point detectors).
These false alarms have two main causes
- High exhaust concentrations fro engines running in stationary cars (e.g. warming up) or because of old-timers producing heavy exhaust emissions set off alarms too quickly in the case of optical smoke detectors.
- Alarms caused deliberately which can be set off e.g. by car park users using a cigarette lighter, etc.

 Serious consequences
Fires in underground garages often cause great damage. Apart from the damage to parked cars which can lead to high compensation sums, irreparable damage is often caused to the structure of the building. In addition, car tyres, petrol, diesel and plastics cause aggressive conflagration gases which can be an additional hazard for both human beings and the environment.

Transafe as an alternative
Installation of the linear heat differential detector TRANSAFE for the automatic detection of fires in car parks and underground garages is a better alternative to smoke detectors or to installing a sprinkler system. TRANSAFE from Securiton offers the following advantages:
- Extremely robust and reliable system which was originally developed for the harsh operating conditions in road tunnels.
- No functional checks required as the system checks itself periodically by means of a fully automatic testing device.
- Thanks to the linear fire detector principle, no false alarms can be set off, e.g. using cigarette lighters.
- No risk of sabotage or deliberate destruction which can occur with point detectors as the sensor tube is very sturdy and is not optically noticeable.
- Adjustable response behaviour.
- TRANSAFE offers zero potential relay outputs for the alarm and fault signal

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