Tenmars Integrating Sound Level Meter

1. Safety Precautions

When taking measurements:

• Avoid measurements in humid or wet places. Ensure humidity is within the limits specified in the "environmental conditions" section.
• Avoid measurements in the presence of explosive gas, combustible gas, steam, or excessive dust.

The following symbols are used:

• Caution: Refers to the user's manual. Incorrect use may damage the tester or its components.
• CE: The instrument conforms to the CE standard.

2. Preliminary Description

The Integrating Sound Level Meter can also survey: SPL(Lxyp), Lxmax, Lxmin, Leq, SEL (LAE), Lcpeak, RT60. It supports three types of frequency weighting (A, C, Z) and three types of time weighting (F, S, I) simultaneously. The dynamic range is over 100dB, eliminating the need to select a measuring range, making operation simple.

Applications: Evaluation of environmental noise, measurements of noise at workplaces, assessment of product noise.

2.1. Note

CAUTION: Failure to observe the warning and/or operation instructions may damage the instrument, its components, or the operator.

• Do not operate the instrument outside the temperature and humidity ranges specified in chapter 13.2.1.
• Keep the microphone dry and avoid severe vibration.
• Wind blowing across the microphone can cause extraneous noise. Use the windscreen to prevent undesirable signals when measuring in windy conditions (Refer to EN-7, Fig.1).

3. Preparation for Use

3.1. Initial

The instrument has been checked mechanically and electrically prior to shipment. Ensure it arrives undamaged. It is recommended to perform a quick check for any transport damage. If damage is found, contact the dealer immediately. Verify the packaging contents against the packing list in section 13.3.1. Contact the dealer immediately in case of discrepancies. For re-shipment, follow the instructions in the relevant chapter.

3.2. Supply Voltage

The instrument is powered by batteries. A low battery indicator will be displayed when batteries are low. Refer to the relevant chapter for battery replacement instructions. The instrument can also be powered by an external power supply (6~9V, 500mA maximum output current).

CAUTION: If the instrument will not be used for an extended period, remove the batteries to prevent acid leakage that could damage the instrument's internal components.

3.3. Calibration

The instrument complies with the technical specifications in this manual and is guaranteed for one year. Recalibration may be required after one year.

3.4. Storage

After storage in extreme environmental conditions exceeding the limits in paragraph 11.2.1, allow the instrument to return to normal measuring conditions before use.

4. Instrument Instructions

4.1. Instrument Description

4.1.1. Controls Description

The instrument features the following controls:

• 1. Microphone
• 2. Power Button
• 3. Backlight Button
• 4. Start or Pause Test Button [▶️ / ⏸️]
• 5. Frequency Weighting Select Button [A/C/Z]
• 6. Time Weighting Select Button [F/S/I]
• 7. Set Button [SET]
• 8. Test function select button [FUNC]
• 9. Record data / Reading Record data button [REC/MEM]
• 10. Data Hold/Up arrow button [HOLD/▲]
• 11. Clock switch/Left arrow button [◀️]
• 12. OK button [OK]
• 13. Clock switch/Right arrow button [▶️]
• 14. Shift switch/End measurement/Down arrow button [▼]
• 15. MICRO SD card slot
• 16. Analog/RS232 professional output
• 17. USB
• 18. DC voltage input (6V~12V)

4.1.2. Display Description

The display shows various indicators:

• Bargraph: Visual representation of sound level.
• Auto Power Off: Indicates the auto power off function is active.
• Reverberation Time: Displays RT60 measurements.
• Data Hold: Indicates data hold is active.
• Peak: Indicates peak measurement.
• Sound exposure level: Displays SEL (LAE) values.
• Sound pressure level: Displays SPL values.
• Equivalent continuous level: Displays Leq values.
• Sound level read out: Displays the measured sound level.
• MAX: Maximum recorded value.
• MIN: Minimum recorded value.
• dBZ: Z Weighting.
• dBC: C Weighting.
• dBA: A Weighting.
• SEC: Reverberation Time unit.
• USB: Indicates USB connection.
• SD: Indicates SD card insertion.
• Low Batty: Low battery indicator.
• REC: Indicates recording is in progress.
• FULL: Memory is full.
• MEM: Memory viewing mode.
• Impulse: Impulse Response weighting.
• Fast: Fast Response weighting.
• Slow: Slow Response weighting.
• 88:88:88: Clock display.
• [▶️ / ⏸️]: Start/Pause Measures.
• [▼]: Stop Measures.
• [SET]: Setup Mode.
• TIME: Measure Time.

4.1.3. ST-107S Microphone

• Diameter: 1/2 inch
• Polarization voltage: 0V
• Dynamic range: 25dBA ~140dB
• Sensitivity: -32±3dB (250Hz 0dB=1V/Pa)
• Free field frequency response: ±2dB(25Hz~12.5kHz)

4.2. Measurement Procedures

• Press [ON/OFF] button to turn the sound level meter on; press again to turn it off.
• Press [FUNC] button to select the test function (Lxyp→Leq→LAE→PeakMAX→RT60).
• Press [F/S/I] button to select time weighting (Fast→Slow→Impulse).
• Press [A/C/Z] button to select frequency weighting (A weighting→C weighting→Z weighting).
• Press [▶️ / ⏸️] button to start the test; press again to pause the test.
• Press [▼] button to stop the test.

The default test mode is Lxyp mode, A weighting, Fast weighting.

CAUTION: Wind blowing across the microphone can cause extraneous noise. If wind speed exceeds 10m/s, mount the windscreen to prevent undesirable signals. Keep the microphone dry and avoid severe vibration.

(Refer to EN-7, Fig.1 for windscreen attachment)

4.3. Data Hold

Press [HOLD] button to lock the display data; press again to unlock.

4.4. Maximum/Minimum

Press [MAX/MIN] button to enter MAX/MIN record mode. The instrument can store maximum/minimum data for up to 99 hours, 59 minutes, 59 seconds. Press [▼] button to end the measurement in advance.

4.5. Single Data Record

Press [REC/MEM] button each time to store the displayed reading and its memory location.

4.6. Viewing Logged Reading

• Press and hold [REC/MEM] for more than 1 second to enter the viewing logged reading mode.
• Press [◀️] or [▶️] buttons to scroll through the readings.
• Press [F/S/I] or [▼] buttons to change the time data format (hh:mm:sec → YY-MM-DD).
• Press [REC/MEM] button again to exit viewing logged reading mode.

4.7. Set Mode

Press [SET] button to enter set mode. Seven functions can be configured in set mode.

4.7.1. Clock Set

• Press [◀️] or [▶️] buttons to select the digit to adjust.
• Press [▲] or [▼] buttons to change the digit.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

4.7.2. Auto Record Time Set

• Press [◀️] or [▶️] buttons to select the option to adjust.
• Press [▲] or [▼] buttons to change the digit.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

Minimum auto record time is 1 second; Maximum auto record time is 23 hours 59 minutes 59 seconds. Setting auto record time to 0 seconds disables the auto record function.

4.7.3. Auto Power Off Time Set

• Press [▲] or [▼] buttons to change the digit.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

To disable auto power off, set the auto power off time to 0. The maximum auto power off time is 99 minutes.

4.7.4. Clear Data Logger Memory

• Press [REC/MEM] button to clear the data logger memory for the last record.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

4.7.5. Clear All Data Logger Memory

• Press [REC/MEM] button. The LCD will flash "ALL".
• Press [REC/MEM] button again to clear all data logger memory.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

4.7.6. Copy All Data Logger To micro SD Card

• Insert the micro SD card before copying data.
• The copied file will be named with the machine ID. The maximum supported capacity of a micro SD card is 32GB.
• The machine ID can be defined by the user in the PC program. The file format is .IAR; the word dollar can be defined as 0~9 or A~F.
• Press [REC/MEM] button to start copying data logger data to the micro SD Card.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.
• Transcend micro SD cards are recommended.
• When using the copy function, use the transformer power supply (DC 6~9V/500mA).
• Format the micro SD card as FAT or FAT32.

4.7.7. Auto Backup

• The auto backup function automatically copies memory data to the miniSD card and deletes the record data.
• Ensure the transformer power supply is connected when using the auto backup function.
• Press [▶️ / ⏸️] button. The LCD will flash "On" to enable automatic backup.
• Press [SET] button to save the settings and exit set mode.
• Press [FUNC] button to exit without saving.

4.7.8. 94dB Calibration

• Input the 94 dBA @ 1 KHz signal to the meter.
• The right bottom LCD displays the current test value. The calibration range is 91.0~97.0dB.
• The left bottom LCD displays the correction data to be written to memory.
• Press [SET] button to save the correction and exit set mode.
• Press [FUNC] button to exit without saving the correction.

5. SPL (LXYP) Test Mode

• In SPL (Lxyp) test mode, the default frequency weighting is A weighting, and the time weighting is FAST.
• Press [▶️ / ⏸️] button to start an Lxyp Max/Min measurement.
• Press [A/C/Z] button to change frequency weighting before starting a measurement.
• Press [F/S/I] button to change time weighting.
• Press [▶️ / ⏸️] button to pause the measurement after starting.
• Press [▼] button to end the measurement in advance.

The LCD shows the measurement duration. The longest record is 99 hours 59 minutes 59 seconds.

6. LEQ Test Mode

• In Leq test mode, the default frequency weighting is A weighting, and the time weighting is FAST. The integral time is 30 seconds.
• Press [A/C/Z] button to change frequency weighting before starting a measurement.
• Press [▶️ / ⏸️] button to pause the measurement after starting.
• Press [▼] button to end the measurement in advance.

The LCD shows the measurement period using a countdown system.

6.1. Integral Time Set

In Leq test mode, press [SET] button to enter the integral time setting. You can select from 9 kinds of integral time or set a custom integral time.

• SET 0: 10 sec
• SET 1: 1 minute
• SET 2: 5 minutes
• SET 3: 10 minutes
• SET 4: 30 minutes
• SET 5: 1 hour
• SET 6: 8 hours
• SET 7: 16 hours
• SET 8: 24 hours
• SET 9: Custom integral time (1 sec to 30 days, 23 hours, 59 minutes, 59 seconds).

Press [SET] button to choose the integral calculus enactment.

Press [◀️] or [▶️] buttons to select the option to adjust.

Press [▲] or [▼] buttons to change the digit.

Press [SET] button to save the settings and exit set mode.

7. SEL (LAE) Test Mode

• In SEL (LAE) test mode, the default frequency weighting is A weighting, and the time weighting is FAST.
• Press [A/C/Z] button to change frequency weighting before starting a measurement.
• Press [▶️ / ⏸️] button to pause the measurement after starting.
• Press [▼] button to end the measurement in advance.

The LCD shows the measurement duration. The longest record is 99 hours 59 minutes 59 seconds.

8. Peak Maximum Test Mode

• In Peak test mode, the default frequency weighting is C weighting, and the time weighting is Peak.
• Press [▶️ / ⏸️] button to pause the measurement after starting.
• Press [▼] button to end the measurement in advance.

The LCD shows the measurement duration. The longest record is 99 hours 59 minutes 59 seconds.

9. RT60 (Reverberation Time) Test Mode

• In RT60 test mode, the default frequency weighting is A weighting, and the time weighting is Fast.
• Press [A/C/Z] button to change frequency weighting before starting a measurement.
• Press [▶️ / ⏸️] button to pause the measurement after starting.
• Press [▼] button to end the measurement in advance.

The MAX value is the first value obtained that is equal to or greater than 90dB. The MIN value is the MAX value minus 60 dB. The reverberation time is calculated from the MAX value to the MIN value.

9.1. RT 60 Estimate Mode

The RT 60 estimate formula is RT60 = (0.161 × V) / SA.

• Press [SET] button to set the room's volume (m³), for example: 10.
• Press [SET] button to set the sound surface absorption value (SA), for example: 1.0.
• Press [SET] button for RT60 estimation, for example: 1.6 seconds.
• Press [FUNC] button to exit RT 60 estimate mode.
• Press [◀️] or [▶️] buttons for input value modification (increase or decrease) for room m³ or SA if necessary.

10. Explanation

10.1. Measurement Parameters:

10.2. A, C, Z Weighting Instruction:

• A: The A weighting curve is based on 40 Phon Fletcher-Munson Equal Loudness Contour. For noise assessment in humans, A weighting is suggested.
• C: The C weighting is essentially approximate smooth. For labor safety concerns, C weighting is suggested.
• Z: The Z weighting is a linear signal processed by the instrument's internal filter. It is suitable for outputting AC or DC signals for research. The Z weighting is a linear signal not processed through the filter and is suitable for AC or DC signal output for research.

10.2.1. Input Interface

The front features a PLT 4 signal input receptacle. Pin definitions are shown in Fig 2:

ST-107:

• Pin 1: Power
• Pin 2: GND
• Pin 3: NC
• Pin 4: NC

ST-107S:

• Pin 1: Power(+)
• Pin 2: GND
• Pin 3: Power(-)
• Pin 4: GND

10.2.2. Analog AC/DC Output

• AC output: 2 Vrms/130dB
• DC output: 2Vdc/130dB

(Refer to Fig 3 for output receptacle and Fig 4 for 3.5mm output plug)

10.3. The Microphone Lengthens The Test

To avoid measurement deviation caused by reflection effects and operational issues, use the extension cable to lengthen the microphone. (Refer to chapter 11.3.2).

1. Press [OFF] button to turn the power off.
2. Separate the preamplifier and microphone from the main body by turning counterclockwise (Refer to Fig 5).
3. Connect the extension cable to the microphone and main body (Refer to Fig 6).

11. Software Installation

1. Visit the website: https://www.tenmars.com/
2. Search for ST-107.
3. Click on the ST-107 photo.
4. Click "File Download", then select "Software Download".
5. Download and unzip the software.
6. For the latest software information and installation procedures, refer to the software installation guide.

12. Maintenance

12.1. General Information

This is a precision instrument. To ensure its performance, use and store it under suitable environmental conditions. Avoid exposure to high temperatures, humidity, or direct sunlight. Turn off the instrument after use. If you do not expect to use the instrument for a long period, remove the batteries to prevent leakage that could damage internal components.

12.2. Battery Replacement

When the low battery indicator is displayed, the batteries need to be replaced.

1. Turn off the instrument.
2. Remove the battery cover.
3. Remove all batteries from the battery holder.
4. Insert four new batteries of the same type, observing the polarity signs.
5. Install the battery cover.

Dispose of waste batteries according to local laws and regulations.

(Fig 1: Opening and closing of battery cover)

12.3. Cleaning

Use a soft, dry cloth to clean the instrument. Never use a wet cloth, solvents, or water.

12.4. End of Life

Caution: This symbol indicates that the equipment and its accessories must be collected and disposed of separately and correctly.

13. Technical Specifications

13.1. Feature

• Environmental conditions: temperature 23°C ± 5°C, relative humidity < 80%.
• Display: Double rows LCD, MAX reading 1999.
• Display Refresh Rate: 1 Time/sec.
• Major Applicable Standards: IEC 61672-1:2002 Class2(ST-107/ST-107S), JJG-188-2002 Class 2(ST-107S).
• Other Standards: IEC60651:1979 TYPE 2(ST-107/ST-107S), IEC60804:2000 TYPE 2(ST-107/ST-107S), ANSI S1.4:1983 Type12(ST-107/ST-107S).
• Microphone(ST-107S): 1/2" pre-polarized condenser microphone with built-in preamplifier: 1V/Pa@250HZ, frequency range: 20 Hz~12.5 kHz, Thermal noise: <25 dB(A).
• Microphone(ST-107): 1/2 inch Electret condenser microphone.
• Measurement Items: Lxyp, Lxmax, Lxmin, Lxeq, LAE, Lcpeak, RT60.
• Measurement Range: 30dB to 130dB (A), 35dB to 130dB (C), 40dB to 130dB (Z).
• Dynamic Range: 100 dB.
• Integrate Time Setup: Randomly, 10s, 1m, 5m, 10m, 30m, 1h, 8h, 16h, 24h.
• Internal memory: 24C512 × 4; MAX Datalogger data >37,000.
• Micro SD Card: Max support capacity is 32GB; 37,000 data points occupy approximately 300KB.
• Maximum Peak C Weighting Sound Level Measurement: 70~133 dB.
• Time Weighting: Fast, Slow, Impulse, Peak.
• Frequency Weighting: A/C/Z.
• Frequency Range: 31.5Hz~8KHz(ST-107), 20Hz~8KHz(ST-107S).
• DC Output: 2Vdc/130dB.
• AC Output: 2Vrms/130dB.
• Starting Time: < 10 Second.
• Battery Life: 30 hours (LR6 : 4 Alkaline batteries).
• AC Adapter: Input: 100V~240V ACV, Output: 6V~9V DCV.
• Dimensions: 285(L) x 90(W) x 39(H) mm.
• Weight: 500g (including Batteries).

13.2. Environment

13.2.1. Environmental Conditions

• For inside use, max height: 2000m.
• Reference temperature: 23° ± 5°C.
• Operation temperature: 5 ~ 40°C.
• Operation humidity: <80% RH.
• Storage temperature: -10 ~ 60°C.
• Storage humidity: <70%.

13.2.2. EMC

This instrument was designed in accordance with current EMC Standards and its compatibility has been tested according to EN61326-2 (2006).

13.3. Accessories

13.3.1. Standard Accessories

• Meter x 1.
• User's manual.
• Switching power supply: 100V ~ 240V AC to DC 6V~9V/500mA.
• Carrying case.
• 4 batteries 1.5 V – LR6 – AA – AM3 – MN 1500.
• 60mm diameter windscreen.
• USB Cable.

14. Service

14.1. Warranty Conditions

This instrument is guaranteed for one year against material or production defects, in accordance with general sales conditions. During the warranty period, the manufacturer reserves the right to decide whether to repair or replace the product. If the instrument needs to be returned for repair or replacement, make prior arrangements with the local distributor. Include a report describing the reason for return (detected fault). Use original packaging. Any damage incurred during transit due to non-original packaging will be charged to the customer.

The warranty does not apply to:

• Accessories and batteries (not covered by warranty).
• Repairs necessitated by improper use (including adaptation to specific applications not foreseen in the manual) or improper combination with incompatible accessories or equipment.
• Repairs necessitated by improper shipping materials causing transit damage.
• Repairs necessitated by previous repair attempts by unskilled or unauthorized personnel.
• Instruments modified by the customer without explicit authorization from the Technical Department.

The contents of this manual may not be reproduced in any form without the manufacturer's authorization. Products are patented, and logotypes are registered. Tenmars reserves the right to modify characteristics and prices as part of technological developments.

14.2. Service

If the instrument is not working properly, before contacting your distributor, ensure that the batteries are correctly installed and working. Check the test leads and replace them if necessary.