Changing The Calibration Level; Calibration - 3M 1200 User Manual

At this point, pressing either the CAL or RESET button will toggle the
Exchange Rate between 'Er3' and 'Er5'.
When the desired Exchange Rate is displayed, store the selection by
pressing both the CAL and RESET buttons simultaneously. This com-
pletes the selection.

3.2.2 Changing the Calibration Level:

NOTE: The calibration level is the decibel level that is produced by
your calibrator.
Turn on the meter.
When the current calibration level is displayed, press and hold both the
RESET and CAL buttons until dashes appear. The meter is now in the
calibration level set mode.
To edit the level, use the RESET key to increase the value and the CAL
key to decrease to value. Edit the value to match your calibrator's output.
When the desired calibration level is displayed, press and hold both the
RESET and CAL buttons until dashes appear on the display. The new
calibration level is now stored in the instruments memory and will not
have to be changed again unless an alternate calibrator is used.

3.3 Calibration:

The model 1200 may be calibrated in any range based on your calibrator's
output. There is no warm up period required, but for maximum accuracy
calibration should be performed at the temperature of the environment to
be measured. To calibrate, perform the following procedure using a Quest
Calibrator.
It is recommended that calibration be performed before each use.
1. Check that the LOBAT indicator is not on.
2. Check to see that the calibrator SPL output matches the calibration
level stored in the meter. If it does not, use procedure outlined in
section 3.2.
NOTE: Failure to match calibrator output level to calibration level stored
in the 1200 will result in erroneous SPL readings.
1200/2200 Sound Level Meter Operator's Manual
Meter Integrity
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