Haier BD-478A service manual

(2)Put freezer onto 5-10mm elastic cushion.

(3)Freezer must be empty and running at least 30 minutes before measuring. If normal stop happens, please make the measurement 3 minutes after freezer starting again.

(4)4 measuring positions are required, they are 1m away from freezer at front, back, front left, front right respectively. The height is 1/2 of freezer; the instrument is accurate sound level meter (A weighted).

12.6.12What’s the different between national noise standard 52dB(A) and ministry of light industry standard 42dB?

Answer: The noise of 52dB(A) in national standard is the sound power level. Under the measuring conditions stipulated in national standard, measure the freezer noise at four points, take the average of indicated reading at greater noise situation, calculate the arithmetic average value of the four points. This value is the average sound pressure level of noise, the calculation formula is:

Lw=(LPA-2)+10LgS

where: LW—sound power level, dB

LPA-average sound pressure level of measuring surface, dB

S—the envelope area of measuring surface, m2

MAINTENANCE SERVICE AND TROUBLE SHOOTING Maintenance Service and Trouble Shooting

The standard 42dB of the ministry of light industry is the noise pressure level measured 1m away from freezer door. This value plus 10 is the

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