Sound level meter - Frequently Asked Questions

Using our standard sound level meter LA-1250/1350, we continuously measure eight values for 24 hours: equivalent sound level (L _Aeq), maximum value (L _Amax), and time-weighted sound levels (L ₅, L ₁₀, L ₅₀, L ₉₀, L ₉₅) at 10-minute intervals. The measured values are automatically saved to the sound level meter's memory. These measured values are then transferred to a PC and used to create tables and graphs in spreadsheet software (Excel).

1. Start the sound level meter.

First, press and hold the panel switch <STORE> while turning the power ON to clear the block memory. Clearing the data will take approximately 3 seconds. Then, turn the power OFF.

• Turn on the power while holding down the <CAL> key.
• Use the <△><▽> buttons to select the measurement condition "COND 2".
• Confirm with <START>.
• Turning on the <KEY PROTECT> button on the bottom will prevent you from changing the measurement conditions.
• For information on checking, changing, and registering measurement conditions, please refer to item 6.
• Contents of COND 2 at the time of shipment

2. Check the operation of the sound level meter.

• Check the battery level.
  
  
• Press <CAL> and confirm that "CAL" is displayed in the lower right corner of the screen.
• Verify that the noise level display shows "104.0 dB" ± 1 dB.
• For details, please refer to the instruction manual, "calibration of the Sound Level Meter."
  
• Check the clock. If it's not correct, turn on the power while holding down <L _p L _eq... (DATE)> and set it. Use <△><▽> to change the value, <FASTSLOW> to advance the digit, and <START> to confirm.
  

3. Start of measurement

• Press <START> to put the device into measurement standby mode.
• When in measurement standby mode, the display will look like the image below.
• The system automatically starts measuring when the measurement start time (Start Time) is reached.
  
• If the measurement start time (Start Time) is not set, measurement will begin as soon as you press <START>, and the display will be as shown in the image below.
  

4. Data Transfer

• Connect the computer and the sound level meter with a cable.
• Turn on the sound level meter.
• Start the "memory transfer" sample program.
• The RS-232C communication conditions setting screen will appear, so set the conditions and press <OK>.
  
• Select "BOLOCK" for "Memory Mode".
• Select the block number to load.
• Specify the save location and file name.
  
• Pressing <OK> will start the transfer.
• Once the transfer is complete, press and hold the <STORE (BM CLEAR)> button while turning on the power to clear the block memory (BM) and prepare for the next measurement.

Please note that block memory will not be overwritten!

5. Processing using Excel 97 spreadsheet

Double-clicking the Excel macro file "LA_Excel.xls" will launch Microsoft Excel and start the macro program. (If your Microsoft Excel settings are configured to "Show a warning dialog when opening a workbook containing macros," a dialog box will appear first; please click "Enable Macros.")

When the macro program starts, a form labeled "SetUp" will appear. Click the "Browse" button on the right and select the text file saved by the sample program. If you know the file name, you can enter it directly, but to avoid typing errors, we recommend clicking the "Browse" button to select the file.

Once you have confirmed that the file name is correct, please click the "OK" button. The file will be automatically read, and a noise summary table and graph will be created.

While creating the graph, input screens for the graph title, X/category axis labels, and Y/value axis labels will appear. Please enter your preferred label names. The first graph created here (Graph 1) will use all the data from the noise summary table, with the horizontal axis representing time and the vertical axis representing noise level. The next graph created (Graph 2) will use the hourly average data from the noise summary table, with the axes set in the same way as Graph 1.

Once you have finished creating the noise summary table and graphs, a form will appear to save the completed workbook. Please enter your desired file name and save it.

Finally, when "Complete" is displayed, press the "OK" button to finish. Please note that the Data1 and Data2 sheets created here are for graph creation purposes only, so do not make any changes to the data.

Changes to the Noise Summary Table Data

This software allows you to delete measured data or change it to any value. Furthermore, after making changes, clicking the "Recalculate" button will automatically adjust the average value and graph to reflect the changes.

1. 1. Please select the sheet "Noise Summary Table".
2. 2. Change the measurement data for the area you wish to modify (LAeq, LA5, LA10, LA50, LA90, LA95).
3. 3. Once you have finished changing all the values, click the "Recalculate" button in the upper right corner of the sheet (near O2). The recalculation will begin.
4. 4. Finally, when "Complete" is displayed, press the "OK" button to finish. If you have made any changes to the data, please save the file before closing the software.

<Notes on data modification>

• Please do not change any data other than the measurement data (LAeq, LA5, LA10, LA50, LA90, LA95).
• When deleting data, please leave at least one data item per hour.

6. Confirmation, modification, and registration of measurement conditions.

You can set the sound level meter's measurement conditions from your computer. These conditions can be saved to the sound level meter's designated panel conditions (COND 1-9).

<Operation>

• Connect the computer and the sound level meter with a cable.
• Turn on the sound level meter.
• Start the "memory transfer" sample program.
• The RS-232C communication conditions setting screen will appear, so set the conditions and press <OK>.
• Select "Condition Number" on the left, configure the settings, and press <Write> to write the measurement conditions to the sound level meter.
  Please refer to the next section for details on the settings.

  

  Example of the "COND 2" setting at the time of shipment

Menu commands and settings

○ Menu bar

○Setting items