Manuals / Tyco / Household Appliance / Smoke Alarm

Tyco 579-769 Advantages, • Backup Power Source Batteries or Generator, Dedicated Power Feed

Models: 579-769

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Advantages

A Typical Emergency Voice/Alarm Communications System

Typical Emergency	The figure below illustrates a typical emergency voice/alarm communications system:
Voice/Alarm
Communications
Communications
System

			Figure 4-1. Typical Emergency Voice/Alarm Communications System
	Advantages	While an emergency voice/alarm communications system is similar to a non-emergency paging
	Advantages	system, there are certain features that make emergency systems much more reliable than standard

		paging systems:
		• Backup Power Source (Batteries or Generator):
			Allows the system to operate for as long as several days during a power failure.
		•	Dedicated Power Feed:
			Isolates fire alarm power circuits from other branch circuits, preventing a fault from a
			non-alarm circuit causing a fault at the fire alarm.
		• Supervision of All Critical Signal Paths:
			From the microphone through the last speaker in the system, all wiring is supervised for
			shorts, opens, and Earth faults.
		•	Access Control:
			Locked cabinet permits only authorized personnel to access to the system.
		•	Fixed Gain Controls:
			The system is factory calibrated and sealed to prevent the user from tampering with the gain,
			avoiding over-driving or under-driving the system.
		•	Local Mode Operation:
			Alarm signals are available even if amplifiers lose communications with the command center.

4-2

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Tyco 579-769 specifications Advantages, • Backup Power Source Batteries or Generator, Dedicated Power Feed, Access Control

Contents

Guideline for Designing Emergency Voice/Alarm Communications Systems for Speech Intelligibility579-769Rev. C Fire Alarm Audio Applications GuidePage Copyrights and Trademarks Page Table of Contents Chapter 1 Speech Intelligibility OverviewChapter 2 Background Information Chapter 3 Speech IntelligibilityChapter 5 Regulatory Issues Chapter 6 Speaker System Design MethodChapter 7 Glossary of Terms Related Publications Topic Chapter Speech Intelligibility OverviewSee Page # Speech Intelligibility Importance Designing for IntelligibilityTopic Chapter Background InformationSee Page # Equation 2-3.Power Relationships V = I ⋅ RP = V ⋅ Basic Audio Math= 20log⎜ Basic Audio Math, Continued20⋅10−6 Sound and Hearing The Relationship Between Sound and HearingIntroduction The Nature of SpeechConsonants and Vowels Room Acoustics Introduction ReverberationRoom Acoustics, Continued • Increasing the Signal-to-NoiseRatio Room Acoustics, ContinuedFigure 2-3.dB and Distance Chart Speaker Basics⎝ D2 Equation 2-8.The Inverse Square LawSpeaker Basics, Continued SPL = Sensitivity + 20 logEquation 2-9. On-AxisSPL Calculation ⎡Dr⎤Simplex Ceiling Mount Speaker1− cos ⎜ 6dB/divisionFigure 2-6.Maximum Theoretical Coverage Angle Figure 2-5.Speaker CoverageSpeaker Basics, Continued Angle Off-Axisθ Polar Loss0.0 dB + Distance LossEquation 2-11.Coverage Area Calculations Listener Height = 5 FeetCeiling CoverageTable 2-2.Layout Pattern Selection Guide Table 2-3.SPL Variation by Layout Pattern2x Edge-to-Edge Minimum OverlapDistributed Wall Mounted Systems Distributed Wall Mounted Systems, Continued Figure 2-8.Wall Mount Speaker Coverage PatternWall Mounted Speakers In Feet RoomEdge-edge Minimum-Overlap Full-Overlap Distributed Wall Mounted Systems, ContinuedChapter Speech Intelligibility TopicSee Page # Influences and IntelligibilityInfluences on Intelligibility No Noise Influences on Intelligibility, ContinuedWith Added Noise Influences on Intelligibility, Continued Continued on next pageDistortion Influences on Intelligibility, ContinuedMicrophone Technique Measures of Intelligibility EXCELLENTGOOD FAIRMeasures of Intelligibility, Continued STI-CISAnalyzer Practical Measurement of IntelligibilityTalkbox Tools for Predicting Intelligibility Introduction Acoustical Modeling SoftwarePage Emergency Voice/Alarm Communications Systems ChapterTopic See Page #Advantages • Backup Power Source Batteries or GeneratorDedicated Power Feed • Supervision of All Critical Signal Paths•A dedicated master microphone Figure 4-2.Class A and B Speaker Circuit Wiring Topic Chapter Regulatory IssuesSee Page # From NFPA 72, 2002 Edition AudibilityFrom NFPA 72, 2002 Edition Audibility, Continued High Background Noise Large AreasIntelligibility Intelligibility, Continued From NFPA 72, 2002 EditionPage Chapter Speaker System Design Method TopicSee Page # Design MethodSpeaker Design Method of the tone with respect to the speech signal Applying the Methods Figure 6-1.iTool Office Space ExampleFlooring = Ceiling =Applying the Methods, Continued Figure 6-2.Office Space Speaker Location GuideFigure 6-3.Office Space SPL Distribution Continued on next pageFigure 6-5.Corridor Design Example Dimensions =Applying the Methods, Continued Flooring =Figure 6-6.Corridor Speaker Location Guide Figure 6-7.Corridor SPL DistributionFigure 6-8.Corridor Reverberation Time Results and Coverage InformationFigure 6-9.iTool Gymnasium Example Dimensions =Applying the Methods, Continued Flooring =Figure 6-10.Gymnasium Speaker Location Guide Figure 6-11.Gymnasium SPL DistributionFigure 6-12.Gymnasium Reverberation Time Results Applying the Methods, ContinuedFigure 6-14.Lobby Example Figure 6-13.Lobby ExampleApplying the Methods, Continued Figure 6-15.Lobby Layout Figure 6-16.Lobby Speaker Location GuideFigure 6-17.Lobby SPL Distribution Applying the Methods, ContinuedApplying the Methods, Continued Lobby, continuedConclusion In ClosingPage Chapter Glossary of Terms TopicSee Page # GlossaryGlossary Glossary or TermsGlossary, Continued Page Index Page Page 579-769Rev. C