Every second counts in early fire detec­tion – whether in data centers, museums, or logis­tics ware­houses. If a fire breaks out in these settings, the stakes are high. Flames, soot, and fire suppres­sants can destroy crit­ical data, works of art, and goods – and in the worst-case scenario, risk human lives. The aspi­rating smoke detec­tors in Securiton’s SecuriSmoke ASD 2000 product family help prevent this: They detect the start of a fire imme­di­ately, based on the very first smoke parti­cles. “To do this, our aspi­rating smoke detec­tors contin­u­ously draw in air through a network of pipes up to 700 meters long,” explains Hakan Sahin, hard­ware devel­op­ment engi­neer and system archi­tect at Securiton. The Switzer­land-based company develops compre­hen­sive and inte­grated secu­rity solu­tions. Active early fire detec­tion is one of its core busi­ness areas. “Unlike passive smoke detec­tors, aspi­rating smoke detec­tors don’t just detect smoke once it has risen to the ceiling. They actively draw air from the surrounding area, enabling them to detect fires early and across large areas.”

Light makes smoke visible

But how does an aspi­rating smoke detector reli­ably detect whether there is smoke in the air? To do this, every aspi­rating smoke detector contains a sensor that oper­ates on the prin­ciple of scat­tered light: The aspi­rated air flows through a measure­ment chamber where light strikes the parti­cles it contains. Smoke parti­cles alter the light scat­tering in a specific way, and the sensor detects this. The upstream internal centrifugal sepa­rator filter (CS filter) sepa­rates larger dust parti­cles from smaller smoke parti­cles, ensuring that only the smaller parti­cles enter the measuring chamber. “This is how our aspi­rating smoke detec­tors reli­ably detect smoke and prevent unwanted false alarms,” adds Hakan Sahin.

The right device for every space

Securiton’s aspi­rating smoke detec­tors monitor the air in a wide variety of appli­ca­tions, from server rooms to large ware­houses. That’s why the SecuriSmoke ASD 2000 product family consists of three models. “Our ASD 2001 is designed for smaller areas up to 3,000 square meters and oper­ates with one duct connec­tion and one smoke sensor. The ASD 2002 uses two duct connec­tions and two inde­pen­dent smoke sensors. And the ASD 2004 features four duct connec­tions, with two of them leading to each of the two smoke sensors. This allows for the moni­toring of signif­i­cantly larger or parti­tioned areas of up to 5,760 square meters,” says Hakan Sahin.

In addi­tion, the aspi­rating smoke detector contin­u­ously moni­tors the airflow in the duct network. Securiton uses ultra­sonic sensors for this purpose. A change in airflow may indi­cate a malfunc­tion in the duct system, such as a duct rupture or a clogged intake opening. As a result, the system not only detects smoke parti­cles but also moni­tors the condi­tion of the duct network.

Nothing works without a fan

For the aspi­rating smoke detector to work, it needs one more key compo­nent. Hakan Sahin explains: “The heart of the system is the fan. It draws in air and chan­nels it through the duct­work to the smoke sensor. This is what makes the prin­ciple of active early fire detec­tion possible in the first place.” The demands placed on the fan are corre­spond­ingly high: “Above all, the fan must be very powerful to trans­port the smoke parti­cles to the smoke sensors quickly enough. In addi­tion, high effi­ciency and a compact design were impor­tant to us during devel­op­ment so that the fan would fit into the limited instal­la­tion space of the aspi­rating smoke detector.”

“We designed the fan for the speed range rele­vant to us – 7,000 to 20,000 rpm.”

Hakan Sahin, hard­ware devel­op­ment engi­neer and system archi­tect at Securiton

The RVE45 from ebm-papst provided the optimal foun­da­tion to address these demands. With a face­plate measuring approx­i­mately 65 by 65 millime­ters, the centrifugal fan delivers substan­tial perfor­mance in a small space. Its dynamic EC internal rotor motor achieves high speeds and responds quickly to changing pres­sure condi­tions. For use in the SecuriSmoke ASD 2000 product family, however, the stan­dard produc­tion model was not suffi­cient. Securiton and ebm-papst jointly tailored the RVE45 to the appli­ca­tion. “We designed the fan for the speed range rele­vant to us – 7,000 to 20,000 rpm – and opti­mized the bearing tech­nology and the elec­trical inter­face for our appli­ca­tion,” explains Hakan Sahin. To this end, both compa­nies also conducted exten­sive testing to imple­ment the indi­vidual require­ments step by step. The temper­a­ture range proved partic­u­larly chal­lenging. The RVE45 is designed to operate just as reli­ably at -30 degrees Celsius as it does at +60 degrees Celsius – and to do so over a long service life. The solu­tion: a special low-temper­a­ture bearing grease.

Fire protec­tion at minimal volume

In addi­tion to suction power, energy effi­ciency, and a compact design, noise levels also play a role – espe­cially in spaces where people spend a lot of time. “Museums are a good example. Here, visi­tors want to expe­ri­ence art and culture – not hear the fire alarm system,” says Hakan Sahin. That’s why Securiton and ebm-papst not only chose a partic­u­larly quiet fan but also designed its instal­la­tion to mini­mize noise and vibra­tion. The result: At the lowest speed, the aspi­rating smoke detec­tors reach a sound pres­sure level of around 21 deci­bels. That’s even quieter than a whisper. As a result, the aspi­rating smoke detec­tors in the SecuriSmoke ASD 2000 product family remain acousti­cally in the back­ground and only sound the alarm when it really matters. For data centers, museums, or logis­tics ware­houses, this means first and fore­most that people are noti­fied early on when smoke develops, providing valu­able time for alerting others and evac­u­ating.