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INSTRUCTION MANUAL
1. General
This document describes the instructions for operating Proximity Exhaust Noise Measurement
System (wireless type).
This is the system for measurement of automobile exhaust noise using the proximity exhaust noise
measurement method in accordance with the safety standards for road transport vehicles (final
revision : August 31, 2001, Ministry of Land, Infrastructure, Transport and Tourism ordinance No.
122)
For detecting engine revolution speed, AVL sensor, which detects revolution speed by sound
vibration, and non-contact type pulse sensor IP-292 or IP-296 are used.
Sound volume meter SV-6224 is used as the sound data input device and microphone can be easily
placed using dedicated microphone stand.
Measurement of the proximity exhaust noise is made by measuring the sound level at a position
rear outside, 45 degrees and 0.5 m from the exhaust pipe, while after keeping the rotation speed
(measurement rotation speed) obtained from the engine rotation speed specified for each vehicle to
be measured for more than several seconds and release the accelerator until it returns to idling
speed, and then obtain the maximum value of the sound level.
Background noise and measurement results are printed by the printer.
2. Features
Engines of the vehicles subject for measurement are following 3 types.
AVL sensor is a dedicated vibration / acoustic type sensor that takes the data from pulse output
from the preamplifier.
Pulse sensor utilizes electromagnetic induction method, and IP-292 is to be used by inserting to the
low-voltage primary side and IP-296 to be used by inserting to the high-voltage secondary side
cable.
* Gasoline engine 2 cycle - motorbikes, etc.
* Gasoline engine 4 cycle - General passenger cars, etc.
* Diesel engine
- Passenger cars, freight cars, etc.
