USER GUIDE Integrating Sound Level Meter and Datalogger Model 407780A
Introduction Thank you for selecting the Extech Instruments Model 407780A. This device is shipped fully tested and calibrated and, with proper use, will provide years of reliable service. Please visit our website (www.extech.com) to check for the latest version of this User Guide, Product Updates, and Customer Support. Features The Sound Level Meter complies with the requirements of IEC 61672‐1:2003 standard for a Class 2 instrument.
Instrument Care Do not attempt to remove the mesh cover from the microphone as this will cause damage and affect the accuracy of the instrument. Protect the instrument from impact. Do not drop it or subject it to rough handling. Transport it in the supplied carrying case. Protect the instrument from water, dust, extreme temperatures, high humidity and direct sunlight during storage and use.
Meter Description 1. 1/2‐inch microphone 2. LCD display 3. Power button 4. Leq / SEL / SPL select button 5. RUN / Pause button 6. UP/DOWN range setting buttons. 7. A / C Frequency weighting select switch 8. FAST / SLOW / IMPULSE time weighting select switch. 1 FAST: 125ms, SLOW: 1 second, IMPULSE: 35ms with slow decay 9. MAX button 2 10. RECORD / ERASE button 11. Real time clock button 12. Integration time button 3 13. Alarm output 4 5 14. AC/DC output 15.
Display Description 1. Sound level range indicator (5 ranges): 30–90dB, 40–100dB, 50–110dB, 60–120dB and 70– 130dB 2. Bar graph represents the current sound level (1dB resolution). 3. Date/time and elapsed time indicator: year ‐ month ‐ day or hour: minute : second. During integrating this indicator displays the elapsed time in seconds. When viewing the Peak Hold value this indicator displays PH. When viewing the percentile values this indicator displays L:05, L:10, L:50, L:90 or L:95. 4.
13. dB: Sound level unit (decibel) 14. A, C: A or C frequency weighting indicator. 15. IMP: Impulse time weighting indicator 16. OVER: Over‐range indicator appears flashing when over‐range measurements have been included in the sound level measurement data recording session. 17. SLOW: Slow time weighting indicator 18. FAST: Fast time weighting indicator 19. : Indicates that integrating sound level measurements have been stopped. 20. : Indicates that integrating sound level measurements are paused. 21.
Operation The meter has two modes of operation, Sound Level Meter mode and Integrating Sound Level Meter mode. Sound Level Meter measurements 1. Press the button to switch the meter ON. The initial state depends on the conditions set when the meter was last switched off. 2. Press the A/C button to select the desired frequency weighting. 3. Press the FAST/SLOW/IMPULSE button to select the desired response time.
Integrating Sound Level Meter measurements The integrating sound level mode will measure the sound level over time and calculate the following results: Leq Equivalent continuous sound level measurement SEL Sound exposure level measurement SPL MAX Maximum sound level measurement SPL MIN Minimum sound level) measurement (PH) Peak Hold sound level measurement Percentile Sound level (L05, L10, L50, L90 and L95) measurement When using this meter in a mode other than the sound level measurement mode, all processi
6. Press the ► ǁ button to start the measurement, the ►symbol and the elapsed measurement time is displayed. When the measurement time has elapsed, the measurement automatically terminates and the symbol is displayed. During measurements, the ► ǁ button can be used to pause and resume a test. During pause, the pause symbol ǁ is displayed. To terminate the measurement, press and hold the ► ǁ button for 2 seconds.
Setting the Current Time and Date Date and time information is stored with each stored record block. Therefore, it is important to ensure that this information is correct. to switch OFF the meter. 1. Press 2. 3. 4. 5. 6. button to switch ON the meter Press and hold the DATE TIME button and then press the to enter the date and time setting mode. A flashing cursor indicates the currently selected parameter (seconds), use the ▲▼buttons to set the current second.
7. To set the recording function to start at a preset time; a) Press and hold the DATE TIME button for 2 seconds to enter the PRESET recording start‐time setting mode, the PrE symbol will be displayed. b) A flashing cursor indicates the currently selected parameter (seconds), use the ▲▼buttons to set the current second. c) Press the DATE TIME button to move to the next parameter (minutes) and use the▲▼buttons to set the current minute. d) Repeat step c) to set the current hour, day, month, and year.
External power source Insert the plug of an AC adaptor or external battery pack into the DC 6V (DC source from 5V to 6V) socket on the side of the instrument. When a connector is inserted into this socket, the internal batteries will be disconnected and the instrument will be powered from the external source. The low battery symbol will appear on the display if the external voltage is insufficient for the instrument to provide accurate measurements.
Calibration Calibrating the Integrating Sound Level Datalogger requires an acoustical calibrator such as the Extech Model 407766 or 407744. 1. Configure the meter as follows: • Display: SPL (dBA) • Time weighting mode: FAST 2. Insert the microphone into the opening of the acoustical calibrator. 3. Switch the calibrator ON. 4.
Maintenance & Cleaning Service not covered in this manual should be performed by qualified personnel Periodically wipe the case with a dry cloth. Do not use abrasives or solvents. Battery Installation When the low battery icon appears on the display, there is insufficient power to make accurate measurements and the batteries must be replaced. 1. Press the 2. Loosen the screw in the battery cover and remove the cover from the battery compartment. Retain the screw and cover. 3.
Specifications Applicable standards: IEC61672‐1: 2003 Class 2 IEC60651: 1979 Type 2 ANSI S1.
Self‐generated noise level: Typical values at 23oC (73.4oF), using the nominal microphone equivalent capacitance of 27pF (30‐90dB range) Weighting Electrical Total A 22.7dB 26.1dB C 21.8dB 29.5dB Linearity operating range: A‐weighted, 1000Hz, 60dB dynamic range. Total linear operating range: In accordance with IEC 61672‐1, A‐weighted, 1000Hz: 30dB to 130dB.
RANGE: 60 – 120 dB. Test starting point 94 dB for all weightings and frequencies except 31.5Hz A‐weighted, for which the starting point is 74 dB. FREQUENCY Hz 31.5 1000 4000 8000 WEIGHTING A A A A L.O.R. dB 60.0 – 80.6 60.0 – 120.0 60.0 – 120.0 60.0 – 118.9 L.O.R. dB 60.0 – 117.0 60.0 – 120.0 60.0 – 119.2 60.0 – 117.0 WEIGHTING C C C C RANGE: 70 – 130 dB. Test starting point 104 dB for all weightings and frequencies except 31.5Hz A‐weighted, for which the starting point is 84 dB. FREQUENCY Hz 31.
Calibration: Acoustical calibrator (Extech 407744 or equivalent) Calibration check frequency is 1000Hz. Nominal calibration level for the free field: 94.1dB Nominal calibration level for the diffuse field: 94.0dB Frequency for acoustic testing: 8000Hz Warm‐up time: ≤ 2min Sampling interval: Bar graph indication 125 ms approx. Numeric indication 1 sec approx. Data record capacity: Data can be stored in memory. Max. 32000 readings can be stored Max.
Power requirements 4 x 1.5V IEC R6P (size “AA”) manganese super heavy duty batteries or equivalent Battery life: Approx. 24 hours External power source: DC voltage from 5V to 6V; Current rating: Approx. 20mA @ 6V Ambient conditions: Operating conditions: ‐10oC to +50oC (14 to 122oF), 30% to 90%RH non‐condensing Storage conditions: ‐10oC to +60oC (14 to 140oF) <70%RH non‐condensing Effect of temperature: < 0.5dB from ‐10 to +50oC (14 to 122oF), Effect of humidity: < 0.
