B&K 2250 Light, User Manual

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2250 Light – User Manual
All the details for the microphone can be found on the screen.
A number of parameters are set automatically for Microphone Type 4950.
Note: For Type 4950 the parameters Nominal Sensitivity , Free-field and Capacitance are set
automatically. See details in Appendix C. The analyzer can then make sound field corrections
and windscreen corrections as specified in the setup. To confirm which type of correction is
being applied, an icon is displayed in the measurement Status field. If the microphone is
unknown to 2250 Light, no corrections can be made and no icon appears in the Status field.
The parameters mentioned above have to be set manually (that is, typed in). We recommend
that you insert the value for Nominal Sensitivity directly from the calibration chart. Nominal
Sensitivity is used in the automatic level detection calculations, when calibrating using Sound
Calibrator Type 4231 Calibrator, to determine whether the level is 94 or 114 dB.
In the top line of the status field you can select which transducer is currently connected to 2250
Light. This can also be done via the
Setup screen by selecting Input, then selecting the
transducer in the Transducer Used: field.
At the bottom of the parameter list you can select the calibration history for the currently
selected transducer by tapping on the
Calibration History link. See section 5.3 and Fig.5.2.
When you have finished, tap to return to the measurement screen.
5.5 Calibration Reminder
The Calibration Reminder tab, see Fig.5.6, allows you to keep track of when you need to run
your next Accredited/Traceable calibration, and shows you the date of your last calibration.
Fig.5.6
Calibration reminder tab
The automatic calibration reminder facility will pop-up a reminder approximately 2 months
before your next calibration is due and keep on reminding you every week until you do one of
the following actions: