Spartan 730/730IS Dosimeter Manual
Calibration
27
Recommended Next Step:
•
2.6.2 About Calibration Histories, Instrument Overload, and Calibration Stability
Calibration Histories
Calibrating your Spartan 730 helps you determine the true sensitivity of your
dosimeter—including all effects from the microphone, preamplifier, and
dosimeter. It also establishes a numeric relationship between the sound pressure
level at the diaphragm of the microphone and the voltage of the meter. Once this
relationship is established, the meter accurately displays the sound pressure
level.
The sensitivity value resulting from each calibration is recorded as a new entry in
the Calibration History table. You can monitor the calibration history of your
meter by connecting your dosimeter to a PC and using G4 LD Utility to view
Calibration Histories. Large changes in sensitivity, or a pattern of small but
regular sensitivity changes, indicate that your dosimeter should be serviced.
Overload Condition
During calibration, your meter determines the overload level (dB Peak) for A, C
and Z frequency weightings.
Simply stated, the overload level is the maximum level the noise dosimeter can
measure accurately. If the meter detects a sounds louder than the overload level,
the Spartan 730 displays an overload indicator on the LCD display, in the LD Atlas
app, in the G4 LD Utility, and in the resulting measurement data.
FIGURE 2-3
Spartan 730 Overload Indicator in the LCD Display
Calibration Stability
The Spartan 730 maintains a stable value of sensitivity over long periods of time.
As part of the meter’s auto-calibration, the result is documented as the
Calibration History.
After the auto-calibration, the dosimeter compares the meter’s current sensitivity
value to the nominal sensitivity for the family of microphones. If the difference is
greater than 5dB, the meter displays a Large Change Notification as shown in
