Kimo DB300/1 User Manual

Contents

Kimo DB300/1 User Manual Manual pdf 52 page image

13 Direction for use and maintenance of the soundlevel meter13.1 Use warningsThe sound level meter is a measuring instrument using the latest technologies. To maintain accuracy and required reliability, avoid anychock of the housing and the microphone and keep them away from humidity and corrosive steams.13.2 Direction for useFor each application, you should check measurement technique and conditions in order to get valid and coherent results. The way ofusing the instrument has at least as much importance on result than device quality. You have to take into account at least the followingparameters:• The sound level meter is designed for a free-field acoustic measurement• The instrument is held with reached out arm for short-time measurement or positioned on a tripod forlong-time measurement.• The axis of the instrument must face sound source, do not interfere with your own body or with anyclose material item (furniture, machines, low wall, trees, etc...).• Protect the instrument from bad weather, and use as much as possible the windscreen. It protects themicrophone and minimizes the disruptive effects linked to air currents during measurement.• Calibrate the instrument regularly with a suitable calibrator CAL300 (class 1) or CAL200 (class 2) type.13.3 CalibrationA calibration must be performed regularly with a suitable calibrator.➢ Insert the adapter ring according to the diameter of the microphone sound level meter.➢ Place the calibrator on the microphone, until the microphone reaches the end of the ring. Do this moveslowly and smoothly so as not to damage the microphone.➢ Put vertically the sound level meter and the calibrator.➢ Turn on the calibrator.➢ Wait for a moment a correct level of acoustic pressure of the calibrator: for example 94.0 dB .➢ You can begin the procedure of calibration of the instrument as explained below.Reminder: free-field coefficientAn acoustic reference source, a calibrator or a pistonphone supplies a level of acoustic pressure. During a free-field measurement, phenomenons of diffraction caused by the microphone and the housing come to affect the measurement. Thisperturbation est minimized if the microphone is far from the housing.For this sound level meter, the induced free-field perturbation is very low, and it is not necessary to introduce a free-field correction.Operating mode➢ From starting screen, select Cal. with arrows keys thenpress OK.Direction for use and maintenance of the sound level meter52Ref : dBC.Cl dBLCF dBCorr. dBCALIBRATION94.00.0---;-0.505/10/2011