噪音測試分原地噪音和行駛噪音
根據CNS 5799第六期機動車輛噪音管制標準值
https://i.imgur.com/JfL1R8t.jpg
汽車出廠加速噪音72~75分貝，原地噪音93~96分貝
機車出廠加速噪音73~77分貝，原地噪音81~92分貝
車輛出廠要測過才能掛牌
其他可以看這篇
#1YRW5yug
環保署的路檢，噪音測試是原地噪音
空載的狀態
https://i.imgur.com/SG6QZXz.jpg
引擎目標轉速(最大轉速50%或75%)
https://i.imgur.com/PWtfJNe.jpg
歐盟可以參考這篇
REGULATION (EU) No 540/2014 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL
of 16 April 2014
https://reurl.cc/8o9AYy
直接看重點
3.1.2
https://i.imgur.com/64wperF.jpg
The background noise (including any wind noise) shall be at least 10 dB
below the A-weighted noise pressure level produced by the vehicle under test.
背景噪音值需低於量測10dBA
4.2. Measurement of noise emitted by stationary vehicles
靜止車輛噪音
4.2.5.2
https://i.imgur.com/d2jUDw0.jpg
the gear selector in the neutral position and the clutch engaged
空檔測試
If the vehicle is fitted with a fan or fans having an automatic actuating
mechanism, this system shall not be interfered with during the sound level
measurements
車輛風扇不應干擾量測
The engine hood or compartment cover, if so fitted, shall be closed
引擎蓋應關閉
4.2.5.3.2.1~3
https://i.imgur.com/fl66FUO.jpg
(1) 引擎轉速條件(1/2, 3/4, 3750rpm)
(2) 與目標轉速誤差3%內，維持1秒
(3) 視為有效量測數據
4.2.6
https://i.imgur.com/DCs3hkw.jpg
At least three measurements for each test position shall be made.
至少量測3次
澳洲的NTC(National Transport Commission)
Noise Test Procedures for In-Service Motor Vehicles
https://reurl.cc/A73WWd
一樣直接看重點
https://i.imgur.com/TZ4JLud.png
wind noise levels are at least 10dB(A) below the noise level being measured
風(背景)噪音應低於量測值10dBA
4.2.1
https://i.imgur.com/mqoFI28.jpg
The vehicle shall be stationary with the transmission in “neutral”
車輛靜止且打空檔
In the case of a motor cycle having no neutral gear position,
measurements shall be carried out with the rear wheel raised off the ground
沒有N檔，應把後輪抬起(無負載)
4.2.3
https://i.imgur.com/wDT8zLM.jpg
引擎轉速(1/2或3/4)，若達不到則以引擎最大轉速95%
4.2.5
https://i.imgur.com/GVBo9UY.jpg
The specified procedure shall be repeated until a least three consecutive
readings are obtained
至少三筆連續的讀數
大部分國家地區噪音標準是跟隨UN ECE R51：汽車噪音 (R41：機車噪音)
測試方法也都大同小異
排放或能耗測試，因為會上Dyno有負載，當然有配置大型工業風扇
但原地噪音測試
1. 空載測試條件哪來很多熱量
2. 測試程序就要求盡量排除環境中的背景噪音值
一直說要風扇撞風真的滿臉問號.....
※ 引述《HulkSmash (~滅世神浩克~)》之銘言：
: 剛剛看到一個影片是環保局驗車
: 看之前的影片，應該是 BMW M3
: 然後就是原地踩油門，聽車主說是6000轉
: 而且還連續催5次，最後都冒煙了
: 先幫車主的引擎默哀10秒
: 好奇驗個車，有需要連續催5次油門嗎??
: 感覺驗車的平常沒開過，所以抓準時機
: 催到底，看能多大聲的感覺 ??
: https://youtu.be/cnsxCh9XCSQ