Sound level meter - Frequently Asked Questions

1. Overview of measurement using dual mode

Dual-mode calculation is a function that simultaneously measures noise levels under separate settings for the main (M) and sub (S) modes. While the sub mode does not have a function to measure time-weighted noise levels, it can simultaneously measure values such as equivalent noise level and single-event noise exposure level, as shown in the following table, under separate settings.

■List of measurement values using dual mode

By performing a time-weighted noise level measurement using dual mode, the following values can be obtained simultaneously:

■ List of restrictions during measurement/pause

During or paused dual-mode calculation and measurement, some panel switches will become unavailable, as shown in the table below. Please note that turning off the power during dual-mode calculation and measurement will forcibly terminate the measurement.

■Signal output

The DC/AC signal output terminal of the sound level meter outputs the main (M) signal.

2. Switching between dual modes

To switch from normal time-weighted noise level measurement to dual mode, press the [Single/Dual] panel switch in Function 2.

<Memo>

• If wide range is selected, you cannot switch to dual mode. Please be sure to select an appropriate range other than wide before switching to dual mode.

3. Switching between main and sub

Dual mode has two types of measurement screens: main and sub. You can switch between main (M) and sub (S) by pressing the [Main/Sub] panel switch in Function 2.

4. Measurement procedure using dual mode

◆Operation

• Activate Dual Mode.
  Pressing the [Single / Dual] panel switch for Function 2 activates Dual Mode.
• Set the frequency correction characteristics and dynamic characteristics for the main and sub channels, respectively.
  After pressing the [Main/Sub] panel switch for Function 2 to switch to the main side (M), set the frequency correction characteristics and dynamic characteristics as follows.
  
  Frequency Correction: Optional (Panel switch [A/C/FLAT])
  Dynamic characteristics: Arbitrary (Panel switch [F / S / IMP])
  
  Similarly, after pressing the [Main/Sub] panel switch for function 2 to switch to the sub side (S), set the frequency correction characteristics and dynamic characteristics as follows.
  
  Frequency Correction: Optional (Panel switch [A/C/FLAT])
  Dynamic characteristics: Arbitrary (Panel switch [F / S / IMP])
  
• Set the following measurement conditions common to both the main and sub-systems.
  
  Display screen: Optional (Panel switch [LIST])
  Level Range: Arbitrary (Panel switch [LEVEL ▲ ▼])
  Measurement value: Arbitrary (Panel switch [L _P / L _eq …])
  
• Set the measurement time.
• Press the [MEAS TIME] panel switch to set the measurement time. To set FREE, switch the set time to 00:00:00. When FREE is set, measurement will continue for up to 100 hours (99:59:60) until the [PAUSE/CONT] panel switch is pressed. However, please note that you cannot set it to more than 100 hours.
• Set the L _X sampling interval (10ms).
• Press the [Period] panel switch on Function 2 to set the sampling interval. If the sampling interval is set to 10ms, overflow may occur if the measurement time is long. Therefore, please set the measurement time to within 1 hour. Also, the overflow time when the measured value changes periodically is as shown in the following table. Please refer to the following table to set an appropriate sampling interval and measurement time.

  

• Perform the measurement.
  Press the [START] panel switch to begin the measurement.
• During measurement, a measurement in progress mark will be displayed, and the elapsed measurement time will be shown in the measurement time setting display.
  
• Read the measured value from the digital display.
  The measurement will end once the set measurement time has elapsed. The measurement progress indicator will also disappear once the measurement is complete.

<Memo>

• Pressing [START] again during measurement will clear (erase) the already measured data and start a new measurement.
• Data that displays an over- or under-level warning during measurement is unreliable. Furthermore, the over- or under-level warning displayed during measurement will not disappear until measurement is restarted.
  If an over-level warning is displayed, set a new level range and perform the measurement again.

■Temporarily suspending measurement

To pause the measurement, press the [PAUSE/CONT] panel switch. When the measurement is paused, the measurement progress indicator will change to a paused indicator. Pressing the [PAUSE/CONT] panel switch again will resume the paused measurement.

5. Reading the measured values

The measured values can be displayed using the following procedure. Note that this also describes how to display the measured results for time-weighted noise level, equivalent noise level, single-event noise exposure level, maximum value, minimum value, and maximum value without leveling.

■Display of measured values via panel switch

Each time you press the panel switch [L _p L _eq …] while the main or sub measurement screen is displayed, the main or sub measurement values will be displayed in the following order: instantaneous value → equivalent sound level → single-event sound exposure level → maximum value → minimum value → maximum value without level conversion → instantaneous value…

■ Display of measured values in list view

When the main or sub measurement screen is displayed, pressing the [LIST] panel switch will initially display the equivalent sound level, single-event sound exposure level, maximum value, minimum value, and maximum value without level conversion for both the main and sub measurement devices. Furthermore, pressing the [L _p / L _eq …] panel switch will display a list of all LX values.