A.    Test Setup and Instrumentation: The test can be performed using a single microphone and rotating the product, or by using multiple microphones. Equipment required for measurement is as follows:

  1.    Regulated AC or DC power supply (as applicable to the UUT or transformer).

  2.    Multichannel oscilloscope with data storage capability or similar equipment for comparing output readings from a photodetector.

  3.    Appropriate attenuator probe(s), if applicable.

  4.    Photodetector capable of measuring relative light output.

  5.    Noise level measurement equipment.

  6.    Microphone(s).

  7.    Isolated sound chamber (e.g., anechoic chamber).

B.    Lamp Seasoning and Preburning: LED lamps shall not be seasoned. 

C.    Input Power for Measurements: The power requirements shall be per IES LM-79 as applicable. Note: When selecting a power supply, it is necessary to apply an appropriate power factor when specifying the Volt-Amp rating of the power supply.

D.    Ambient Temperature: testing of the UUT shall take place in an ambient temperature of 25°C ± 5°C. Drafts shall be minimized.

E.    Power Meter: Power meters shall be capable of measuring to the appropriate requirements of IES LM-79 as applicable.

F.    Environmental Conditions: The test environment shall be clean and free from large amounts of dust and moisture.

G.    Sample Selection: Samples shall be representative of the manufacturer’s typical product. The samples shall be clean and thoroughly inspected before testing. Any flaws or inconsistencies in the samples shall be noted. The samples used for noise testing shall be the same sample(s) used for testing for meeting Joint Appendix JA10, if applicable, and can be the same sample(s) used for other testing.