Trane TRG-TRC007-EN manual ARI Standard

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period four

Equipment Sound Rating

notes

ARI Standard 260

IUses reverberant- room method

ITests entire air handler, not just fan

IAll common configurations and components included

IIncludes effects of secondary sound sources

Figure 66

The objective of ARI Standard 260–2001, Sound Rating of Ducted Air Moving and Conditioning Equipment, is to deliver sound data that accurately represents the acoustical impact of the air-handling equipment after it is installed.

This standard uses the reverberant-room method to measure the sound generated by the entire air handler, not just the fan. As mentioned, a fan performs differently inside an air handler than it does in a stand-alone application. The air-handler casing generally changes the airflow patterns at the fan inlet and discharge openings. This effect is the major reason for the difference between fan-only sound data and the actual sound produced by the air handler after it is installed.

To eliminate such inaccuracies, ARI 260 requires that the entire air handler be tested in all of the configurations in which the equipment is commonly applied in the field. This involves the four test configurations discussed in Figure 64, as well as various combinations of options such as inlet and discharge plenums, different types of filters, dampers, coils, and so forth.

Unlike the other methods, ARI 260 requires that secondary sound sources, such as return or exhaust fans and compressors, be tested to determine their acoustical impact on the air handler. Any secondary source that alters the sound spectrum of the supply fan must be included in cataloged ratings.

In summary, ARI 260 addresses a wide range of air-handling equipment with a consistent test method. It ensures accurate, verifiable sound data, and focuses on the entire air handler in all of its common installation arrangements. ARI 260 enables designers to make equitable product comparisons, and to more accurately predict sound-pressure levels for occupied spaces.

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Contents Air Conditioning Clinic Fundamentals of Hvac Acoustics Business Reply Mail Comment Card One of the Fundamental SeriesFundamentals of Hvac Acoustics Preface Fundamentals of Hvac AcousticsContents TRG-TRC007-EN Fundamentals of Sound Fundamentals of SoundWhat is Sound? What is Sound?Sound Wave and Frequency Wavelength Broadband Sound Broadband Sound and TonesOctave Bands Octave BandsLogarithmic sums One-Third Octave Bands Sound Power and Sound Pressure Sound Power and Sound PressureAn Analogy DB = 10 log DecibelLogarithmic Scale 10 ´ logEquation for Sound Power Equation for Sound PressureLogarithmic Addition of Decibels 50 dB + 44 dB = 51 dBHuman Ear Response Sound Perception Rating MethodsHuman Ear Loudness Contours Single-Number Rating Methods Response to TonesSingle-Number Rating Methods C Weighting Sound Perception and Rating MethodsWeighting Example Weighting Noise Criteria NC Curves NC-39 Room Criteria RC Curves MPa DB ref Pressure Sound Perception and Rating Methods RC-31 R Phon and Sone Octave-Band Rating Method Octave-Band Rating MethodAcoustical Analysis Acoustical AnalysisSetting a Design Goal Setting a Design GoalAcoustical Analysis Acoustical Analysis Source-Path-Receiver AnalysisSource-Path-Receiver Model Typical Sound Paths AirborneExamples of a Single Sound Path Example of Multiple Sound PathsIdentifying Sound Sources and Paths Modeling Sound Paths Sound-Path ModelingSupply Algorithms for Sound-Path Modeling Computerized Analysis Tools Attenuation and Regeneration Terms Used in Sound-Path ModelingSound Transmission Insertion loss IL Noise reduction NR Transmission loss TL Absorption Reflected Sound Receiver Sound Correction Equipment Sound Rating Equipment Sound RatingFree Field Fields of Measurement= L p1 20 log Distance Correction in a Free FieldLot Near Field Reverberant Field Semireverberant Field Rating Hvac Equipment Hvac Equipment Sound RatingReverberant-Room Method Free-Field Method Industry Standards Ducted Air-Handling Equipment Air Handler Test Configurations Former Methods of Sound Testing ARI Standard Sound Power by Octave Band Review Review-Period OneReview-Period Two Noise criteria NC Room criteria RCReview-Period Three Review-Period Four Review Quiz Questions for PeriodOctave-band frequency, Hz Answers Glossary Glossary Room effect See receiver room correction Glossary Trane
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