The attenuation from the terminal to the room is.
From c) we subtract.NR-values are entered in line.Custom-made products for various challenges coupled with suitable accessories are part of our day-to-day work.That is why our solutions stand for maximum customer benefit and heating reliable long-term protection.Check against domestic rules.Remember to include supply and return fans.With our experience and know-how, we are the best partner in terms of cable protection.We offer you duct various standard solutions for requirements such as impact and vibration protection, protection against the ingress of moisture and dirt, noise/abrasion protection as well as heat protection in high-temperature applications.Add Safety factors, add safety factors - 3 dB is recommended.Together with our customers, we develop heating and implement solutions perfectly tailored to the specific needs of the automotive industry.The sound pressure levels, lp - are converted to sound power level, lw - at the terminals.Note that the table and diagrams list the attenuation in dB/m.Attenuation due to end reflection is entered below.C) Find the rooms absorption characteristics. Manufacturer's data are preferred.
Sound pressure level criterion Determine the sound pressure level criteria.In the example the listener is approximately.5 m from the terminal.Calculate Resulting Sound Power and duct Required additional Attenuation.Silencer requirements The silencer must be selected noise to provide the necessary attenuation.Power-level split, main duct noise to branch duct Determine the allowance for split - main duct to branch.Power-level split, branch to terminals Determine the allowance for split - branch to terminals.B) Determine whether the receiver are in noise the direct or reverberant field.Resulting Sound Power Fan Subtract summarized attenuation from the fan sound power - inclusive safety factors. We are, however, quite aware of the fact that each and every cable protection noise application has to face different requirements, customized developments for the automotive area are therefore our specialty.
We consider reliable cable protection to be as important as simple handling heating during installation and a wide diameter range for every demand.
Allowance for end reflection, in the example the duct dimension is 250.
The values are entered in the example.