• Title/Summary/Keyword: Photoelectric smoke detector

Search Result 15, Processing Time 0.016 seconds

Optical Properties for Smoke Particles of Fire Sources According to UL 268 (UL 268 화원에 의한 연기입자의 광학적 특성)

  • Jee, Seung-Wook;Lee, Jong-Hwa
    • Fire Science and Engineering
    • /
    • v.28 no.2
    • /
    • pp.9-13
    • /
    • 2014
  • This paper is basic study for development of the photoelectric-type smoke detector that is able to distinguish fire source as well as fire detection. For this subject, Light source and sensor which is normally used for the conventional smoke detector are assembled for the optical chamber. Using 3 type of the test fires (the paper fire, the wood fire, the flammable liquid fire) this paper attempts to find optical properties of each fire. These 3 type of fire are used in the testing of smoke detector according to UL 268 standard. As the result, there are disambiguated between the paper fire and the wood fire in scattering and reason of extinction in the flammable liquid fire is different from that of the paper and the wood fire.

A study on the Development of Smoke Detector Sensitivity Test Equipment (휴대용 연기감도시험기 개발에 관한 연구)

  • Kim, Hyeong-Gweon;Kwon, Seong-Pil;Yoon, Hun-Ju;SaKong, Seong-Ho
    • Fire Science and Engineering
    • /
    • v.23 no.5
    • /
    • pp.125-132
    • /
    • 2009
  • In this study we could contribute to the development of a precise checking tool with which the reliability of the automatic fire detection systems was enhanced and the safety of the people was ensured. In the same way as the domestic technical standard, the portable smoke sensitivity tester, which was developed in this work, could be used to check the capability of the smoke detectors installed in the field. Its heater inside was warmed up to $400^{\circ}C$ in 40 seconds and the paper as a smoke source was burned to produce smoke for the test. With the Photoelectric smoke detector it was possible to measure and control the smoke concentration in a range from 0%/m to 25%/m. With the adjustment of rpm of the fan, it was possible to keep a constant wind velocity in a range from 20cm/sec to 40cm/sec.

A Study on Response Characteristics of Photoelectric Type Smoke Detector Chamber Due to Dust and Wind Velocity (분진 및 풍속에 따른 광전식연기감지기 챔버의 응답특성에 관한 연구)

  • Lee, Chun-Ha;Lee, Ho-Sung;Kim, Si-Kuk
    • Fire Science and Engineering
    • /
    • v.31 no.1
    • /
    • pp.50-57
    • /
    • 2017
  • The present article discusses the response characteristics of smoke detector chamber due to dust and wind velocity. Although situations have improved in terms of early sensing of fires as the smoke detectors are applied indoors, studies tend to place insufficient focus on the side effects and malfunction that can be caused by diversified life dust produced indoors and environmental requirements, etc. Therefore, in the present study, 4 types of photoelectric smoke detectors with different forms and structures of smoke chamber were selected as the experimental objects, and dust test was conducted with fly ash, talcum powder and fiber dust as experiment samples to study indoor applicability of the smoke detectors in terms of their response to diversified dust and wind velocity. Also, to observe response characteristics due to pollution level inside the smoke chamber, wind velocity for dust test were set additionally at 0.25 m/s, 0.5 m/s, and 1.0 m/s. Based to the experimental results, fly ash, talcum powder, and fiber dust (black hair powder) were found to be suitable at the dust test reference wind velocity conditions of 0.25 m/s for both operation test and non-operation test after dust application. On the other hand, under the harsh wind velocity conditions of 0.5 m/s and 1.0 m/s, malfunction of unwanted alarm was observed in non-operation tests in the case of fly ash and talcum powder, and non-operation was confirmed to occur in the case of fiber dust as the alarm failed to operate normally in operation tests.

A Study on the Adaptability of the CO Sensor as A Fire Detection Sensor According to the Test Fire Source of UL 268 (UL 268 시험화원에 따른 CO센서의 화재감지센서로서의 적용성에 관한 연구)

  • Lee, Chun-Ha;Sung, Want-Ki;Lee, Jong-Hwa;Kim, Hyeong-Gweon;Jee, Seung-Wook;Kim, Si-Kuk
    • Fire Science and Engineering
    • /
    • v.28 no.2
    • /
    • pp.54-63
    • /
    • 2014
  • The purpose of this study is to test the adaptability of the CO sensor as a fire detector by analyzing its sensing characteristics on fire. In order to test the applicability, we designed and made a fire testing ground whose size is similar to that regulated by UL 268, carried out real fire tests suggested by UL 268, and conducted a comparison analysis on the sensing characteristics between the CO sensor and a photoelectric smoke detector by different types of fire source. The experiment result to the sensing characteristics of the CO sensor is about twice to three times faster than that of the photoelectric smoke detector, proceeding with incomplete combustion such as paper and wood fire source in the initial fire. Especially in case of wood smoldering fire, sensing characteristics of the CO sensor is very excellent.