TaxTMI 
TaxTMI 
1996 (11) TMI 204
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....arned Collector rejected the plea for classification under 90.27. Sub-heading 9027.80 inter alia, covers other instruments and apparatus for measuring or checking the quantities of heat; while sub-heading 85.31 deals with electric sound or visual signalling apparatus (for example, bells, sirens, indicator panels, burglar or fire alarms). It was pleaded before the Collector by the appellants that the Explanatory notes under Heading 85.31 appearing at page 1383 rules out for fire alarms incorporating smoke detectors containing a radio active surface (Heading 90.22) since the smoke detector imported by the appellant contains a radio active source. It was pleaded that the classification under 85.31 was ruled out in terms of the above said Expla....
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.... developing fire exceed the critical limit, the instrument initiate an alarm. Therefore, it is a fire alarm under sub-heading 8531.10 and not other as an instrument and apparatus for measuring or checking the quantities of heat. 3.  Arguing for the appellants, the Learned Advocate, Shri V.R. Mulick relied on the submissions made before the lower authorities. He submitted that the instrument is not a fire alarm and which does not give any alarm in terms of a bell or a signal. It merely passes on an information to the other gadgets. The Learned Advocate also relied on the ruling rendered in the case of BHEL v. Collector of Customs, as reported in 1989 (39) E.L.T. 53 (Tribunal) = 1988 (18) ECC. T 111. 4. The Learned DR, Shri K.....
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....be sudden gusts of wind in excess of 10 meters/sec. The operating principle of the item states that the detector contains an ionisation chamber consisting of a small Americium 241 radioactive source mounted between two metal electrodes to which a voltage is applied. The alpha particles emitted by the americium ionise the air into positive and negative ions which separate and travel to electrodes of opposite sign. Some ions collide and recombine, but the net result is flow of a small electrical current, in the order of 2 X 10" amps, between the electrodes. When smoke particles enter the chamber ions become attached to them. As the particles are very much larger than the ions and collide more frequently, an increase in the rate of ion recombi....
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.... positive and negative supplies through the detector, including detector to mounting base supply connections. It further states that the smoke entering the open chamber causes the gate of TR1 to become more negative. When the turn on voltage of TR1 is reached its source to drain resistance switches from several megaohms to a few ohms. The current through TR1 develops a voltage across resistor R2 and triggers the SCR into a conducting state. This results in illumination of the light emitting diode LED via diode D2 and resistor R3 and R8 and the switching off of TR 1. On a reading of this material it is clear that the item is a smoke detector and the smoke is measured in ionisation chamber and states of a signal when the smoke occurs a par....
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....the manufacturer's literature. He further states that these detectors are sensitive to visible and invisible smoke particles, produced during the incipient stages of a developing fire. The certificate states that this is the only function of the said smoke detector, which is conformed by IS : 2189-1988, which defines in clause 4.1.2.1 the ionisation smoke detectors as detectors employing ionisation chamber as sensing means for detecting aerosols give-off by fires. The certificate states that the smoke detector is only to detect the presence of smoke in a given area and is suitable for detecting slow and rapidly developing fire producing visible or invisible smoke particles. It cannot by itself give any sound or alarm or audio signals, even ....