Sound Reception Device ZÖLLNER SRD414/2 BSH /4615/ /09 CONFORMITY WITH DNV NAUT-A REQUIREMENTS

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2 Sound Reception Device ZÖLLNER SRD414/2 BSH /4615/ /09 CONFORMITY WITH DNV NAUT-A REQUIREMENTS DNV401 The Sound reception system (SRS) shall be capable of detecting sound signals from ship whistles operating in the audio band 70 Hz Hz whilst suppressing wind and mechanical noise within this band as well as frequencies outside this band. The SRS performance shall endure microphones being located in a position having an ambient noise level of 70 db(a). DNV402 The SRS shall have means for muting of audio signals up to 75 db(a) to adjust for more severe ambient noise levels in rough weather. If the means provided for muting involves mechanical adjustment by the operator the pertinent UID shall indicate the muting threshold in steps of no more than 3 db(a). DNV403 The SRS shall include filters suppressing background noise from wind and own ship s machinery letting only sounds having a characteristics reckoned to be a ship s whistle pass through. Sufficient noise suppression can normally only be obtained by digital filtering techniques. DNV404 The SRS shall be capable of determining the approximate direction to the source of the sound signal. The SRS shall as a minimum indicate the source of the sound signal being to port or starboard side and forward or abaft of the beam. DNV405 The accuracy of the determination of the applicable quadrant shall be within ±5º. The sectors of ambiguity (s) along the longitudinal and transversal axis of the ship shall either be insignificant (<10º) or be determined and indicated as separate directions (sectors). If a higher resolution than the 4 sectors is provided, (typically 4n where n = 2, 4, etc.), then the accuracy requirements applies analogous to the separation of the available directions (sectors). ZÖLLNER 401 The ZÖLLNER Sound Signal Direction Detector SRD414/2 is be capable of detecting sound signals from ship whistles operating in the audio band 70Hz-820Hz whilst suppressing wind and mechanical noise within this band as well as frequencies outside this band. The SRD414/2 performance endures microphones being located in a position having an ambient noise level of 70 db(a). These facts are given proof of by the existing BSH type approval certificate. ZÖLLNER402 The SRD works on electronic principles with automatic muting of irrelevant signals. ZÖLLNER403 Signal analyzing of the SRD414/2 is done by a microprocessor. ZÖLLNER404 The SRD414/2 is capable of determining the approximate direction to the source of the sound signal, indicating the source of the sound signal being to port or starboard side and forward to abaft the beam. This is certified by he exixting BSH type approval certificate. (Can be tested / checked with test generator.) ZÖLLNER405 The SRD414/2 is able to determine the applicable quadrant.the direction of the microphones goes along with the longitudinal and transversal axis of the ship.so here is no ambiguity to the longitudinal and the transversal axis of the ship. The accuracy of determination of the applicable quadrant is better than ±5.

3 Sound Reception Device ZÖLLNER SRD414/2 BSH /4615/ /09 CONFORMITY WITH DNV NAUT-A REQUIREMENTS DNV406 The resolution of direction to the source of the sound signal shall not be lesser than the four quadrants plus the four sectors of ambiguity. If a dual axis display (e.g. a CROSS or 4 LEDs) is used for visually presenting the direction to the signal source then two axes or two LEDs should be used to represent the accurate quadrant. When the direction to the signal source is within the longitudinal or transversal sectors of ambiguity only one axis or LED shall lit to enhance the perception of the direction by the user. If an SRS makes use of 4 microphones located in a defined configuration comparing the signal time delay involving the two signals (microphones) on the same axis this time difference is a function of the direction of the incidence of the signal and will approach zero when the axis of incidence is near normal to the axis of the microphones. The accuracy with which the SRS can determine the time delay will determine the sector of ambiguity. ZÖLLNER406 The 8 LEDs for indicating the direction are arranged at 45 DNV407 The sound reception display shall give a clear visual indication of the direction for at least the duration of the sound signal plus 2 seconds. The direction (or quadrant) shall be clearly readable by day and by night on a distance of not less than 2 metres. ZÖLLNER407 The SRD414/2 display gives a clear visual indication of the direction for at least the duration of the sound signal plus 2sec.The direction ( or quadrant) is clearly readable by day and by night at a distance of not less than 2 meters. The display can be tested by using the system s test box. DNV408 The loudspeaker(s) should be installed so that incoming sound signals are audible at all working positions inside the wheelhouse for which the OOW has been assigned tasks. Elephant E ars ZÖLLNER408 The master control unit of the SRD414/2 has one loudspeaker with volume adjustment to the ambient noise level which normally is sufficient for perception of the incoming sound signals. On vessels with very large bridge additional slave panels with loudspeakers may be installed. Elephant Ears T ONE T ONE Tes t Tone Generator S ound R eception Device S R D 414/2 TTG Tes t Tone Generator S ound R eception Device S R D 414/2 TTG Art.no

4 Sound Reception Device ZÖLLNER SRD414/2 BSH /4615/ /09 CONFORMITY WITH DNV NAUT-A REQUIREMENTS F DNV409 The microphones shall be installed away from noise sources and in lee of strong wind and otherwise abide by the instructions of the manufacturer. ZÖLLNER409 Ideally the microphone sensor unit shall be installed on the signal mast. If this is not possible, it shall be installed on the top Front of the bridge as far away as possible from large superstructures and sources of noice like funnel, radar or ventilation, ideally on a seperate rigid mast. Minimun distance from magnetic compass: Master control unit - 2 meters Microphone sensor meters. 4 Microphones DNV410 The system shall be muted upon activation of own ship s whistle and outdoor PA-system. DNV411 Sound intensity in the wheelhouse It shall be possible to adjust the sound intensity level (volume) of the loudspeaker. ZÖLLNER410 The SRD414/2 is cabable of muting the ship s own whistle and outdoor PA-system, the master control unit is provided with a mute-pin. ZÖLLNER411 For sound intensity the master control panel is provided with a volume control potentiometer. DNV412 The volume knob of the loudspeaker shall have a mark of the position where the sound level in the wheelhouse is alike the sound level at the outdoor listening post. The OOW shall be able to set the sound intensity of the reproduced signal measured 1 m from the loudspeaker(s) in the wheelhouse (with all bridge windows and doors closed) to the same level as the sound intensity that is measured outside the wheelhouse at a location near the microphone that is closest to the signal source. ZÖLLNER412 The mark of the position where the sound level in the wheelhouse is alike the sound level at the outdoor listening post must be marked on the bridge console at site. 413 With the volume control adjusted to the out door level and in the absence of any intelligible sound signal the SRS shall be muted. ZÖLLNER413 Muting in the absence of any intelligible sound signal works automatically.

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6 Cruise Liner >>Brilliance of the Seas<< with ZÖLLNER Signal Equipment 3 ZET-Horns - 1 Automaton - Electric Bell and Gong - Elephant Ears SRD 414/2