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Rion NA-28 Instruction Manual

Other manuals for NA-28: Instruction Manual

Summary of NA-28

  • Page 1

    3-20-41 higashimotomachi, kokubunji, tokyo 185-8533, japan http://www.Rion.Co.Jp/english/ instruction manual sound level meter na-28.

  • Page 3

    I organization of the na-28 documentation documentation for the sound level meter na-28 comes in three parts, as listed below. Instruction manual (this document) describes operating procedures for the sound level meter na-28, connec- tion and use of peripheral equipment such as a level recorder and ...

  • Page 4

    Ii.

  • Page 5

    Iii organization of this manual this manual describes the features, operation and other aspects of the sound level meter na-28 (with 1/3 octave analysis function). If the unit is used together with other equipment to confi gure a measurement system, consult the documentation of all other components ...

  • Page 6

    Iv memory card explains how to use a memory card with the unit. Input/output connectors explains the input and output connectors of the unit. Default settings lists the factory default settings of the unit. Setup file explains how to start up the unit using settings saved in a setup fi le. Optional ...

  • Page 7: Caution

    V for safety in this manual, important safety instructions are specially marked as shown below. To prevent the risk of death or injury to persons and severe damage to the unit or peripheral equipment, make sure that all instructions are fully understood and observed. Caution important d isr ega r d ...

  • Page 8

    Vi.

  • Page 9: Quantifi Er Notation

    Vii quantifi er notation (sound level and sound pressure level are expressed uniformly as sound pres- sure level, distinguished by the use of frequency weighting.) display on na-28 measurement value the time weighting characteristics f, s, 10 ms i l p sound pressure level a-weighted sound pressure l...

  • Page 10

    Viii.

  • Page 11

    Ix quantifi er notation of sound level meter na-28 according to international standards and jis (excerpts from iso 1996, 3891, iec 61672-1:2002, jis z 8202, 8731) de s cription fre que ncy we ighting is o nota tion iec nota tion j is nota tion na-28 nota tion s ound le ve l l p l p l p a-we ighte d ...

  • Page 12

    X.

  • Page 13: Precautions

    Xi precautions operate the unit only as described in this manual. The na-28 is a precision instrument. Protect it from shocks and vibrations. Take special care not to touch the microphone diaphragm. The diaphragm is a very thin metal fi lm which can easily be damaged. Use only the microphone/preampl...

  • Page 14

    Xii to ensure continued accuracy, have the unit checked and serviced at regular intervals. When using the unit for commercial purposes or for certifi cation, offi cial certifi cation is required every fi ve years. Contact the supplier. Dispose of the unit and of batteries only according to national ...

  • Page 15

    Xiii contents organization of the na-28 documentation ..................................... I organization of this manual ........................................................ Iii outline ............................................................................................1 controls and fu...

  • Page 16

    Xiv calibration ....................................................................................33 electrical calibration ..........................................................33 power on/off ................................................................................37 to turn the unit ...

  • Page 17

    Xv store operation ............................................................................. 81 inserting and removing the cf card ......................................84 manual ....................................................................................85 memory store ....................

  • Page 18

    Xvi.

  • Page 19: Outline

    1 outline the sound level meter na-28 allows octave and 1/3 octave band analysis in real time. It conforms to legal requirements for quantity measurements and to jis and iec standards. It supports diffuse sound fi eld measurements and also meets standard requirements when the supplied windscreen is ...

  • Page 20

    2 outline the sound level meter na-28 allows the following quantity measure- ments. Main processing (sound level meter mode, analyzer mode) simultaneous measurement of all items with selected time weighting and frequency weighting characteristics sound level l p equivalent continuous sound level l e...

  • Page 21: Controls And Functions

    3 controls and functions front view microphone/preamplifi er the microphone/preamplifi er unit can be detached from the main unit and connected via an optional extension cable. This allows use at a separate location. Be sure to use only the microphone/preamplifi er assembly with the number as shown ...

  • Page 22: Operation Key Panel

    4 controls and functions operation key panel start/stop key press to start or stop the measurement (including the various processing functions). Store key serves to start the auto store process or to perform manual store for en- tering data into the memory. Mode key switches the processing mode. Eac...

  • Page 23

    5 controls and functions level keys (level range switching keys) serve for selecting the level range for measurement. In sound level meter mode, the following six settings are available. 20 to 80, 20 to 90, 20 to 100, 20 to 110, 20 to 120, 30 to 130 db in analyzer mode, the following six settings ar...

  • Page 24: Memory Card Slot Cover

    6 controls and functions cal key (calibration key) this key is used for calibration of the unit and for level calibration of connected equipment. Slm/rta key (sound level meter/real-time analyzer key) this key switches between sound level meter mode and real-time analyzer mode. Menu key this key ser...

  • Page 25: Bottom View

    7 controls and functions bottom view cover this cover protects the connectors on the bottom during transport or stor- age. Removing the cover gives access to the connectors shown above. External power supply jack the supplied ac adapter nc-94a can be connected here for powering the unit from an ac o...

  • Page 26: Rear View

    8 controls and functions rear view name plate shows various information including model number of the unit, microphone number, preamplifi er number, serial number, and date of manufacture. Tripod mounting thread the unit can be mounted on a camera tripod using this thread. Battery compartment four b...

  • Page 27: Preparations

    9 preparations power the na-28 can be powered by four iec r14, size c batteries (alkaline or manganese) or the ac adapter nc-94a. Rechargeable batteries may also be used, but the na-28 does not have a facility for charging the batteries. Note when the ac adapter is connected, the unit will be powere...

  • Page 28: Important

    10 preparations important take care not to reverse the (+) and (-) polarity when inserting the batteries. Always replace all four batteries together. To prevent the risk of damage, do not mix old and new batteries or batteries of different type. To prevent the risk of battery fl uid leakage, re- mov...

  • Page 29: Windscreen (Ws-10)

    11 preparations windscreen (ws-10) when making outdoor measurements in windy weather or when measuring air conditioning equipment or similar, wind noise at the microphone can cause measurement errors. Such effects can be reduced by using the wind- screen ws-10. You can use a compensation feature to ...

  • Page 30: Diffuse Field Correction

    12 preparations diffuse field correction you can use a compensation feature to ensure fl at frequency response in a diffuse sound fi eld. 1. Select [measurement] from the menu list and press the ent key. 2. Select [diffuse field correction] from the menu and set it to on. 3. Press the menu key to re...

  • Page 31: Inserting A Card

    13 preparations memory cards (cf card) and program cards measurement data can be stored on a memory card for use and further pro- cessing in a computer. Optional program cards can also be used for loading software into the na-28 to expand the measurement functions of the unit. Inserting a card impor...

  • Page 32: Important

    14 preparations microphone extension cables (ec-04 series) be sure to turn power to the unit off before separating the microphone from the main unit. To reduce measurement deviations due to refraction effects and the acoustic infl uence of the operator, the microphone can be detached from the unit a...

  • Page 33

    15 preparations 2. Connect the extension cable to the preamplifi er and to the main unit and fasten the connectors with the fastening screw. 3. When mounting the microphone on a tripod, fi rst fasten the micro- phone holder (supplied with the extension cable) to the tripod. Then insert the extension...

  • Page 34: Connection To A Printer

    16 preparations connection to a printer the usb port on the bottom of the unit can be used for connection to a usb printer, using the printer connection cable. Connection to a level recorder (lr-07, lr-20a) sound level recording connect the ac output jack on the bottom to a level recorder, as shown ...

  • Page 35: Connection To A Computer

    17 preparations connection to a computer the usb port on the bottom of the unit can be used for connection to the rs-232c interface or usb port of a computer, using the optional serial i/o cable or usb connection cable. Dc 5-6v trig in/ comp out ac dc output usb open cover on bottom usb port to comp...

  • Page 36: Setting The Date and Time

    18 preparations setting the date and time the na-28 incorporates a clock which allows recording the date and time along with measurement data. Set the date and time as described below. 1. Press the power key to turn the unit on. 2. Press the menu key. The menu list screen appears on the display. 3. ...

  • Page 37

    19 preparations system menu screen to select [time setting] and press ent key / / / keys use system -- time setting screen to select item to set use ent key to select digit / / / keys use / use keys to change value press ent key to move on press ent key to accept.

  • Page 38

    20 preparations note an internal rechargeable backup battery serves to keep clock setting on the unit and to store measuring data in internal memory. Those data and clock set- ting will be gone if the unit is not used for a certain period or the backup battery is empty. The backup battery is automat...

  • Page 39

    21 preparations measurement in a dark location pressing the light key will turn on the display backlight, for easier read- ing in a dark location. The backlight operation pattern can be controlled via a menu, as follows. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to sele...

  • Page 40: Sub Channel Settings

    22 preparations sub channel settings to use the sub channel, you must make certain settings on a menu screen. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [measurement] and press the ent key. The measurement menu screen appears. 3. Use the keys to select [sub cha...

  • Page 41: Trigger Mode Settings

    23 preparations trigger mode settings the na-28 offers a trigger mode whereby measurement is initiated by one of three kinds of trigger: time trigger (time-controlled triggering), level trig- ger (sound level controlled triggering), and external trigger (triggering by an external signal). Time trigg...

  • Page 42: Time Trigger Setting

    24 preparations time trigger setting for auto1 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [store] and press the ent key. 3. Use the keys to select [store mode] and press the ent key. 4. Use the keys to select [auto1] and press the ent key. 5. Press the menu key...

  • Page 43

    25 preparations for auto2 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [store] and press the ent key. 3. Use the keys to select [store mode] and press the ent key. 4. Use the keys to select [auto2] and press the ent key. 5. Press the menu key to bring up the menu...

  • Page 44: Sleep Mode

    26 preparations sleep mode if time trigger has been selected for the auto1 or auto2 mode, you can enable sleep mode (power-saving standby mode). When sleep mode is enabled, the unit will enter a power-saving standby condition before the measurement is started and during intervals between measurement...

  • Page 45

    27 preparations in the measurement standby condition, the indicator led fl ashes in blue using the following pattern. 0.1 second intervals 5 seconds lit out lit lit out lit.

  • Page 46: Level Trigger Setting

    28 preparations level trigger setting 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [measurement] and press the ent key. 3. Use the keys to select [trigger mode]. 4. Use the keys to select [level*] and press the ent key. Level1: measurement starts when trigger lev...

  • Page 47: External Trigger Setting

    29 preparations external trigger setting 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [measurement] and press the ent key. 3. Use the keys to select [trigger mode] and press the ent key. 4. Use the key to display the trigger mode. 5. Use the keys to select [ext.]...

  • Page 48: Comparator Output

    30 preparations comparator output this is an open collector output that can be used to control external equip- ment. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [i/o(input/output)] and press the ent key. 3. The input/output menu is shown. Use the keys to select ...

  • Page 49: About The Comparator Output

    31 preparations about the comparator output when the sub channel is off, the comparator will not function if sub chan- nel is selected as comparator band. Similarly, if analyzer mode is set for simultaneous analysis of octave and 1/3 octave bands, and 16 khz or 20 khz is selected as comparator band,...

  • Page 50: Language Selection

    32 preparations language selection the language used for displaying messages and menus can be selected as follows. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [system (language)] and press the ent key. 3. The system menu screen appears. Use the keys to select [l...

  • Page 51: Calibration

    33 calibration before starting a measurement, the na-28 must be calibrated. There are two types of calibration, namely electrical calibration using an internally gener- ated signal and acoustic calibration using an external sound calibrator. Electrical calibration calibration is carried out using a ...

  • Page 52

    34 calibration signal output for calibration of external equipment the normal level range setting for calibration is 30 to 120 db, but for calibra- tion of external equipment, another level range setting can also be chosen. In this case, ''xx db'' fl ashes on the calibration value indication. The ca...

  • Page 53: Important

    35 calibration acoustic calibration with sound calibrator nc-74 for acoustic calibration, a sound calibrator (pistonphone) is mounted to the microphone of the sound level meter, and adjustment is performed so that the reading of the meter is equal to the sound pressure level inside the coupler. 1. T...

  • Page 54

    36 calibration 8. Press the cal key. If ''internal calibration'' is shown under the bar graph, press the store key. The indication will change to ''acoustic calibration''. 9. Use the keys to adjust the reading of the na-28 to the value shown below. Sound calibrator nc-74: 94.0 10. Press the cal key....

  • Page 55: Power On/off

    37 power on/off to turn the unit on hold down the power key until the power-on screen appears (at least 1 second). When the screen is shown, release the power key. After the unit has been initialized, the measurement screen appears. During initialization, the indicator led fl ashes blue green red. G...

  • Page 56: To Turn The Unit Off

    38 power on/off to turn the unit off hold down the power key until the unit is turned off (several seconds). When the power-off screen appears, release the power key. Note after turning the unit off, wait at least 10 seconds before turning it on again. If the key lock has been activated, pressing th...

  • Page 57: Reading The Display

    39 reading the display sound level meter mode screen the illustration below shows all elements of the display for explanation pur- poses. In actual operation, such a screen will not be shown, and the size and font of the actual display may be slightly different. Comparator on/comparator level when t...

  • Page 58

    40 reading the display address shows the current memory address. In manual store mode, the indication is red if there are data in that address. In auto1 mode, the store cycle is shown. Store mode shows the selected mode for storing data in memory (manual, auto1, or auto2). Level range shows the uppe...

  • Page 59

    41 reading the display current date and time shows the current date and time. Key lock pressing the grp/num key and menu key simultaneously activates the key lock condition and causes this symbol to appear. To cancel the condi- tion, press the grp/num key and menu key once more together. Battery sta...

  • Page 60

    42 reading the display main channel time weighting indicates the main channel time weighting characteristic. F: fast, s: slow, : 10 ms main channel frequency weighting indicates the main channel frequency weighting characteristic. A: a-weighting, c: c-weighting, z: flat response measurement in progr...

  • Page 61

    43 reading the display trigger mode controls the measurement and memory store start behavior. Available modes are level1, level2, time, and ext. Diffuse sound correction indicates that the unit has been set up for measurement in a diffuse sound fi eld..

  • Page 62: Analyzer Mode Screen

    44 reading the display analyzer mode screen an example for the oct & 1/3 oct analysis screen is shown below. Use the and keys of the keys to move to the target fre- quency. T-l (time/level) display screen an example for the 1/3 oct analysis screen is shown below. Cursor frequency and level at cursor...

  • Page 63: Numeric Display Screen

    45 reading the display numeric display screen examples for oct, 1/3 oct, and oct·1/3 oct analysis screens are shown below. Numeric display (oct) screen numeric display (1/3 oct) screen numeric display (oct, 1/3 oct) screen frequencies that are currently not displayed can be called up with the / keys...

  • Page 64: Indicator Messages

    46 reading the display indicator messages when keys such as start/stop or store are pressed, indicator messages such as shown below will appear on the display for about 1 second. When start/stop key was pressed and processing has started when store key was pressed (store address is also shown) when ...

  • Page 65: Menu List Screen

    47 reading the display menu list screen pressing the menu key brings up the menu list screen as shown below. Use the keys to select the desired menu and press the ent key. System use the keys to select [system (language)] and press the ent key. The system menu comes up. Cf card format off/exec. (can...

  • Page 66

    48 reading the display read/save setting bring the cursor to [read/save setting] and press the ent key. The [system -- setting] screen appears. / / / keys to select the item and press the ent key. Use the [system -- settings -- save] screen appears. Return menu / / / keys to select the item and pres...

  • Page 67

    49 reading the display time setting bring the cursor to [time setting] and press the ent key. The [system -- time setting] screen appears. Program information bring the cursor to [program information] and press the ent key. The [system -- settings -- program information] screen appears. Language 日本語...

  • Page 68: Display

    50 reading the display display use the keys to select [display] and press the ent key. The display menu screen appears. Max hold on/off (can be selected in analyzer mode) leq on/off le on/off lmax on/off lmin on/off ln1 (l01 to l99) on/off ln2 (l01 to l99) on/off ln3 (l01 to l99) on/off ln4 (l01 to ...

  • Page 69: I/o (Input/output)

    51 reading the display i/o (input/output) use the keys to select [i/o (input/output)] and press the ent key. The input/output menu screen appears. Ac out off/main/sub dc out off/main/sub comparator on/off usb communication on/off remote control on/off backlight brightness dark/bright backlight auto-...

  • Page 70

    52 reading the display comparator menu level use the keys to select [comparator] and press the ent key. The following menu appears. Comparator on/off comparator level 25 to 130 db (1-db steps) comparator band sub ap/main ap/12.5 hz/16 hz/20 hz/25 hz ... 20 khz, 1/3 octave bands) input/output -- comp...

  • Page 71: Store

    53 reading the display store use the keys to select [store] and press the ent key. The store menu appears. Store mode manual/auto1/auto2 store name man_**** au1_**** au2_**** **** is a 4-digit number from 0000 to 9999 sampling period (slm/rta) (only shown in auto1 mode) slm: 100 ms rta: 1 to 10 ms (...

  • Page 72: Measurement

    54 reading the display measurement use the keys to select [measurement] and press the ent key. The measurement menu appears. Wind screen correction on/off measurement time auto1 1 s to 1000 h auto2 (normal measurement) 1 s to 24 h back-erase off/5 s delay time 1 to 10 s lmax/lmin type band/ap (can b...

  • Page 73

    55 reading the display trigger mode menu level use the keys to select [trigger mode] and press the ent key. The following menu appears. Available trigger mode settings are level 1, level 2, time, and ext. Level 1 setting items trigger level 25 to 130 db, 1-db steps trigger band main ap/sub ap/12.5 h...

  • Page 74: Print

    56 reading the display sub channel menu level use the keys to select [sub channel] and press the ent key. The following menu appears. Measurement-sub chnnel screen measurement-sub chnnel print use the keys to select [print] and press the ent key. The print menu screen appears. Printing screen.

  • Page 75: Recall

    57 reading the display recall use the keys to select [recall] and press the ent key. The select file menu appears. Select file menu screen.

  • Page 76

    58 reading the display menu list items system cf card format read/save settings [v]---------- load default group save for cf card [v]---------------- list of setting groups on cf card group loading/delete for cf card [v]---- list of setting groups on cf card time setting ----------------year/month/d...

  • Page 77: Measurement

    59 measurement when using the na-28 in a mode other than "sound level measurement", all processing functions provided by the unit ( l eq , l e , l max , l min , l n ) are car- ried out simultaneously. (however, for the sub channel, only the additional processing function set to "on" in the menu scre...

  • Page 78

    60 measurement 2. Use the freq weight key to select the frequency weighting characteristic. For normal sound level measurements, select the "a" setting. When lz (flat) is selected for display, the sound pressure level from 10 hz to 20 khz is measured with fl at characteristics. When lc (flat) is sel...

  • Page 79: Important

    61 measurement 5. The level indication shows the currently measured sound level (sound pressure level). The reading is updated once every second. The pause/cont key can be used to stop and resume the updat- ing of level indication. In sound level meter mode, the bar graph indication will be updated ...

  • Page 80

    62 measurement note the na-28 performs high-speed sampling of the sound pressure waveform (15.6 µs; 20.8 µs when octave and 1/3 octave analysis is performed simul- taneously) to determine l eq and l e . It is therefore not affected by dynamic characteristics. However, the impulse setting for equival...

  • Page 81

    63 measurement 6. Set the measurement time from the menu. Press the menu key to bring up the menu list screen. 7. Use the keys to select [measurement] and press the ent key. The measurement menu screen appears. 8. Use the keys to select [measurement time] and press the ent key. 9. Use the keys to se...

  • Page 82: Important

    64 measurement 11. Use the keys to select [leq] and press the ent key. 12. Use the keys to select on and press the ent key. 13. Press the start/stop key to return to the measurement screen. For information about how to use the back-erase function to exclude data, refer to page 76. 14. Press the star...

  • Page 83

    65 measurement during measurement, the pause/cont key can be used to pause and resume the measurement. During pause, the pause symbol ( ) is shown. (the paused interval and the back-erase interval are not included in the measurement time.) if the back-erase function was enabled in steps 7 and 8, usi...

  • Page 84: Sound Exposure Level (

    66 measurement sound exposure level ( l ae ) measurement the procedure for sound exposure level measurement is similar to that for equiva- lent continuous sound level measurement, but the menu item selection differs. Preparations as described in the "preparations" chapter must be completed fi rst. 1...

  • Page 85: Important

    67 measurement important during measurement, the level keys, freq weight key, and time weight key function as markers. The start/stop key, mode key, pause/cont key, light key, and power key are operative. Be sure to complete all settings before starting the measurement. During measurement, the pause...

  • Page 86: Maximum Sound Level (

    68 measurement maximum sound level ( l max ) and minimum sound level ( l min ) measurement the procedure for maximum sound level and minimum sound level measure- ment is similar to that for equivalent continuous sound level measurement, but the menu item selection differs. Preparations as described ...

  • Page 87: Important

    69 measurement while the measurement is in progress, the symbol fl ashes and the elapsed time is displayed. When the measurement time has elapsed, the measurement is terminated automatically. To terminate the measurement before the allocated time, press the start/stop key. If signal overload or an u...

  • Page 88: Selecting The

    70 measurement note during measurement, you can use the mode key to check the equivalent continuous sound level as cur- rently calculated. (this applies only to the numeric level display. The bar graph shows the sound level.) after the measurement is completed, changing the frequency weighting (a/c/...

  • Page 89: Percentile Sound Level (

    71 measurement percentile sound level ( l n ) measurement the procedure for percentile sound level measurement is similar to that for equiva- lent continuous sound level measurement, but the menu item selection differs. Preparations as described in the "preparations" chapter must be completed fi rst...

  • Page 90: Important

    72 measurement if signal overload or an under-range condition occurs at least once during measurement, the indication over or under appears, to indicate that overload or under-range data are comprised in the processed values. Important during measurement, the level keys, freq weight key, and time we...

  • Page 91: ) Measurement

    73 measurement additional processing value ( l peak , l atm5 ) measurement when the na-28 is in sound level meter mode and the sub channel is on, the following processing functions are available in addition to l eq , l e , l max , l min , and l n . L peak : peak sound level l atm5 : time-weighted ta...

  • Page 92: Important

    74 measurement 6. Select l peak / l tm5 . 7. Press the start/stop key to return to the measurement screen. 8. Use the level keys to set the level range. Choose a setting in which the bar graph indication registers to about the middle of the range. If the "over" or "under" indicators appear frequentl...

  • Page 93: Important

    75 measurement important l ai is the time-weighted sound level. Processing for this value begins when the start/stop key is pressed, and the display is updated ac- cordingly. The display will not be updated when processing has stopped. Therefore using the manual mode is recommended for l ai . Note d...

  • Page 94: Back-Erase Function

    76 measurement back-erase function when a measurement is being carried out and data are being processed, the pause/cont key can be used to pause the measurement. Normally, data up to the point at which the pause/cont key was pressed will be included in processing, but the back-erase function makes i...

  • Page 95: Marker

    77 measurement marker during processing of leq and other values, it is possible to add markers to the data. 1. Select the store mode on the main menu. Also set the required measurement parameters such as frequency weighting and time weighting. 2. Press the start/stop key to set the unit to the measu...

  • Page 96: Max Hold

    78 measurement max hold this function retains the maximum value for one second, for easier reading of the changing bar graph indication. 1. Press the menu key to bring up the menu list screen. 2. Select [display] to bring up the display menu screen. 3. Select [max hold] and press the ent key. 4. Sel...

  • Page 97: Delayed Measurement

    79 measurement delayed measurement the na-28 allows setting a delay time to be inserted before the actual start of the measurement. 1. Press the menu key to bring up the menu list screen. 2. Select [measurement] to bring up the measurement menu screen. 3. Select [delay time] and press the ent key. 4...

  • Page 98

    80 measurement when the trigger function is also used, the start of measurement will be delayed by the preset delay time from the trigger event point. When a delay time has been set, the na-28 will operate as follows. When the start/stop key is pressed, the measurement standby symbol starts to fl as...

  • Page 99: Store Operation

    81 store operation the na-28 can store measurement data (processed data such as sound level and equivalent continuous sound level, and measurement parameters such as frequency weighting and time weighting characteristics) in the internal memory or on cf card. This chapter describes how to store data...

  • Page 100: Auto2

    82 store operation analyzer mode continuous store of sound level l p values for each band and all-pass main channel: all-pass value and band level values sub channel: all-pass value sampling cycle: 1 ms to 1 sec, l eq,1s internal memory: max. 10000 data (2.7 hours for 1 sec or l eq,1s ) auto2 sound ...

  • Page 101

    83 store operation note an internal rechargeable backup battery serves to keep clock setting on the unit and to store measuring data in internal memory. Those data and clock set- ting will be gone if the unit is not used for a certain period or the backup battery is empty. The backup battery is auto...

  • Page 102

    84 store operation inserting and removing the cf card insert or remove the cf card as shown below. 1. Slide 2. Lift 1 2 cf card card slot lever (push to remove card) engage this section with your nail to open the cover. Front side cf card insertion indicator this symbol is shown when a cf card is in...

  • Page 103: Manual

    85 store operation manual memory store at the point where the store key is pressed, the current sound level and processing values are stored. Immediately after turning power on, there will be no processing values, therefore only the sound level is stored when the store key is pressed. If no cf card ...

  • Page 104

    86 store operation 5. Use the keys to select [manual] and press the ent key. 6. Specify the store name. 6-1. Use the keys to select [store name] and press the ent key. 6-2. Use the keys to specify the fi rst two digits and press the ent key. 6-3. Press the ent key or the key to move to the next two ...

  • Page 105

    87 store operation 9. Specify the store address. The currently selected address is shown on the screen. If the address is shown in red, it already contains data. Take care not to overwrite data that you want to keep. The keys can be used to specify the address in the range from 0001 to 1000. Any dat...

  • Page 106: Important

    88 store operation important any measurement data present in the currently displayed address will be overwritten. If the address is shown in red, it contains data. Take care not to accidentally overwrite data. Note when address 1000 is reached, it will be overwrit- ten without confi rmation. When th...

  • Page 107

    89 store operation start/stop key power key menu key ent key mode key slm/rta key / / / keys select store name with and press ent key / keys recall screen, sound level meter mode recall screen, analyzer mode.

  • Page 108: Erasing Stored Data

    90 store operation erasing stored data to erase data stored in manual mode, proceed as follows. Note data are erased in store name units. It is not possible to selectively erase data for a specifi c address. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [recall] a...

  • Page 109: Auto1

    91 store operation auto1 sound level meter mode l p , l eq , l max , l min are stored as 1 set of data every 100 ms. Using a cf card, the maximum measurement duration is 1000 hours, and using the internal memory 3 hours. Analyzer mode the level for each band and l p are stored continuously on the cf...

  • Page 110

    92 store operation 6. Use the keys to select [sampling period] and press the ent key. Use the keys to set the sampling period and press the ent key. In sound level meter mode, the setting is fi xed to 100 ms. 7. Set other measurement parameters (measurement time, trigger mode, sub channel etc.) as r...

  • Page 111: Important

    93 store operation 9. Press the store key to start the measurement. Important during measurement, only the start/stop key, mode key, light key, store key, freq- weight key, time weight key, level key and power key are operative. Be sure to complete all settings before starting the store process. Dur...

  • Page 112: Recalling Stored Data

    94 store operation recalling stored data the procedure for recalling data stored in memory is described below. 1. Turn power to the unit on. 2. Press the menu key to bring up the menu list screen. 3. Use the keys to select [recall] and press the ent key. The fi le selection menu appears. 4. Use the ...

  • Page 113

    95 store operation power key menu key ent key mode key slm/rta key / / / keys recall screen, sound level meter mode recall screen, analyzer mode.

  • Page 114: Erasing Stored Data

    96 store operation erasing stored data to erase stored data, proceed as follows. 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [recall] and press the ent key. 3. The fi le selection screen appears and stored data are displayed. Use the keys to select the data that...

  • Page 115: Auto2

    97 store operation auto2 sound level meter mode measurement value data derived from main processing and additional processing, along with information about measurement date/time, are stored at preset intervals. Analyzer mode all-pass level and band level values and main processing values are stored ...

  • Page 116: Recalling Stored Data

    98 store operation 8. Use the measurement menu to set the [measurement time] and [trig- ger mode]. 9. Set other measurement parameters (sub channel etc.) as required, using the menu key to select setting items. 10. Press the start/stop key to return to the measurement screen. 11. Press the store key...

  • Page 117: Memory Card

    99 memory card using a memory card open the cover of the memory card slot and insert a cf card. To remove the card, push the lever so that the card pops out. Important make sure that power is off before inserting or removing a card. 1. Slide in arrow direction 2. Lift 1 2 cf card card slot lever (pu...

  • Page 118: About Memory Cards

    100 memory card about memory cards be sure to use memory cards available separately from rion co., ltd. The memory cards that can be used in this unit are compactflash tm cards. * compactflash is a trademark of san disk corporation. Memory cards even from the same manufacturer and of the same type e...

  • Page 119: Auto1 Store

    101 memory card auto1 store the fi le name specifi ed on the menu screen is used for the subdirectory name and the lower four digits of the header fi le name. The header fi le contains measurement parameters and other information. The data fi le contains the sound pressure level, over-range informat...

  • Page 120: Important

    102 memory card formatting (initializing) a cf card important formatting (initializing) a cf card will erase all data present on the card. A cf card can be formatted either in a computer or in the na-28. The procedure for formatting the card in the na-28 is described below. 1. Press the menu key to ...

  • Page 121: Input/output Connectors

    103 input/output connectors ac output 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [i/o (input/output)] and press the ent key. 3. Use the keys to select [ac out] and press the ent key. 4. Use the keys to select [main/sub] and press the ent key. It is a frequency-...

  • Page 122

    104 input/output connectors the relationship between the display value shown by the na-28 and the output voltage is indicated below. When the na-28 is set to the calibration mode, the output signal (level range upper limit 120 db -6 db, 1000 hz) is 0.5 vrms. Output v oltage (vrms) 10 1 0.1 0.01 0.00...

  • Page 123: Dc Output

    105 input/output connectors dc output 1. Press the menu key to bring up the menu list screen. 2. Use the keys to select [i/o (input/output)] and press the ent key. 3. Use the keys to select [dc out] and press the ent key. 4. Use the keys to select [main/sub] and press the ent key. The signal is avai...

  • Page 124: Trig In/comp Out Jack

    106 input/output connectors trig in/comp out jack the trig in/comp out jack is located at the bottom of the unit. A connection diagram for the trig in/comp out jack is shown below. The optional splitter adapter cc-59 is required for using the trig in/comp out jack. If the output cable cc-24 (monaura...

  • Page 125

    107 input/output connectors trig in (trigger input) 0 to 5 v logic-level signal, falling edge trigger, pulse width 1 ms or more comp out (comparator output) logic level 0 v pulse width > 1 ms comparator output approx. 480 Ω tr time comparator le v el signal output continues for 1 second after level ...

  • Page 126: Default Settings

    108 default settings the factory default settings of the unit are listed below. Calibration mode ............................................. Internal slm/rta ....................................................... Slm mode ............................................................... Lp main cha...

  • Page 127

    109 default settings l n4 ................................................................... 90 l n5 ................................................................... 95 additional processing value ............................. Lpeak store mode .......................................................

  • Page 128: Setup File

    110 setup file loading settings from a setup fi le at startup has the following advantages: setup fi le stored on cf card is loaded automatically and establishes the desired settings, allowing quick measurement start. If settings were changed by mistake, simply turning the unit off and on again will...

  • Page 129

    111 setup file preparing a setup fi le for automatic loading 1. Set the na-28 to the intended condition, so that measurement pa- rameters and other settings are as desired. 2. To enable automatic loading, a simple preparatory step is required using a computer. This can be realized in two ways: (1) r...

  • Page 130

    112 setup file automatic loading of settings at startup 1. Insert a cf card prepared as described in the preceding section "preparing a setup fi le for automatic loading" into the na-28, and turn power on. 2. A dialog appears asking whether to load the settings. Select "yes" at this dialog or wait f...

  • Page 131: Saving A Setup Fi Le

    113 setup file saving a setup fi le save procedure 1. Set the na-28 to the intended condition, so that measurement pa- rameters and other settings are as desired. 2. On the menu screen, select [system], then select [read/save setting] and press the ent key. 3. Bring the cursor to any position betwee...

  • Page 132

    114 setup file copying a setup fi le to cf card up to fi ve setup fi les can be saved in internal memory. If you want to create more setup fi les, or if you want to automatically load a setup fi le at startup, the cf card can be used. The na-28 does not allow directly saving settings in a fi le on t...

  • Page 133: Optional Accessories

    115 optional accessories microphone extension cables (ec-04 series) for enhanced measurement accuracy, the microphone can be detached from the unit and connected via an extension cable. This will reduce measure- ment deviations due to refraction effects and the acoustic infl uence of the operator. S...

  • Page 134: Printer

    116 optional accessories printer data gained during measurement and data stored in the memory of the na-28 and on cf card can be printed out on a printer. You can also produce hard copy of measurement screens. (the printer, printer paper, and printer cable are options.) to print measurement data, tu...

  • Page 135: Printing Stored Data

    117 optional accessories printing stored data the steps for printing stored data are described below. 1. On the menu list screen, select [recall] and press the ent key. 2. Use the keys to select the stored data that you want to print. 3. When you press the ent key, the stored data are displayed. Men...

  • Page 136

    118 optional accessories 4. When you press the ent key once more, the recall menu list screen appears. Select [print] and press the ent key. 5. A display such as shown below appears. If you want to print only a range of data, select "data range print" and specify the range. Then select "execute" and...

  • Page 137: Sound Level Recording

    119 optional accessories level recorder lr-07/lr-20a by connecting a level recorder to the na-28, the sound level changes over time can be recorded. Sound level recording the procedure for recording sound level changes over time is described below. Turn power to the na-28 and the level recorder on. ...

  • Page 138

    120 optional accessories 6. Adjust the level control (level adj) of the level recorder so that the pen registers at -6 db from the top of the scale. 7. Press the cal key once more to return the na-28 to the measure- ment mode. 8. Use the freq weight key to set the frequency weighting character- isti...

  • Page 139: Program Cards

    121 optional accessories program cards the na-28 can make use of a range of optional program cards. For details on usage, refer to the documentation supplied with the respective card..

  • Page 140: Remote Control

    122 optional accessories remote control the remote control (na-27rc1) can be used to control the basic functions and measurement parameters of the sound level meter. This is achieved by pressing buttons arranged on the panel of the remote control. The operation range of the remote control is 3 meter...

  • Page 141: Important

    123 optional accessories insert two iec r03, size aaa batteries (lr03 or r03) into the battery compartment on the rear of the remote control. 1. Pull the cover of the battery compartment down while pushing on the section marked with the symbol. 2. Insert two iec r03, size aaa batteries, taking care ...

  • Page 142: Specifi Cations

    124 specifi cations applicable standards general measurement law: precision sound level me- ters iec 61672-1:2002 class 1 iec 61260:1995 class 1 ansi s1.11-2004 class 1 ansi s1.4-1983 type 1 ansi s1.43-1997 type 1 jis c 1509-1:2002 class 1 jis c 1513:2002 class 1 jis c 1514:2002 class 1 iec 60804:20...

  • Page 143

    125 specifi cations measurement items main processing (sound level meter mode, analyzer mode) simultaneous measurement of all items, using selected time weighting and frequency weighting sound level l p equivalent continuous sound level l eq sound exposure level l e maximum sound level l max minimum...

  • Page 144

    126 specifi cations measurement time processing time 1 to 59 seconds, 1 to 59 minutes, 1 to 24 hours processing types in each operation mode main processing additional processing channel main sub add slm ap/oct ap ap ap frequency weighting a/c/z a/c/z same as sub time weighting f/s/10 ms f/s/10 ms/i...

  • Page 145

    127 specifi cations frequency weighting a, c, z time weighting main channel f, s, 10 ms sub channel f, s, 10 ms, i linear operating range all-pass (a-weighting) 115 db spectrum 95 db level range sound level meter mode display range max. 100 db 30 to 130 db 20 to 120 db 20 to 110 db 20 to 100 db 20 t...

  • Page 146

    128 specifi cations diffuse sound fi eld correction frequency response correction to ensure standard compliance in diffuse sound fi eld correction on/off setting via menu display backlit semitransparent tft lcd display (240 × 320 dots) update frequency: 100 ms trigger function controls measurement a...

  • Page 147

    129 specifi cations manual store data for selected measurement results and measure- ment start time are stored manually, in single address increments. Data store capacity internal memory max. 1000 data sets cf card max. 1000 data sets per store name, the number of store data depends on the capacity ...

  • Page 148

    130 specifi cations auto2 sound level meter mode continuous store of main pro- cessing and additional processing values and measurement start time on cf card, using preset measurement interval analyzer mode continuous store of main process- ing all-pass value and band level values and measurement st...

  • Page 149

    131 specifi cations dc output main channel or sub channel signal can be selected. Output voltage 3.0 v, 25 mv/db at range full- scale point output impedance 50 Ω load impedance 10 k Ω or more comparator output open-collector output band-level determination also possible connector is shared with exte...

  • Page 150

    132 specifi cations supplied accessories cf card 128 mb 1 storage case 1 soft case 1 ac adapter nc-94a 1 windscreen ws-10 1 bnc-rca cable cc-24 1 hand strap 1 size c battery lr14 4 instruction manuals (instruction manual, serial interface manual, technical notes, 1 each) 1 set inspection certifi cat...

  • Page 151

    133 specifi cations optional accessories sound calibrator nc-74 cf card remote control na-27rc1 usb printer battery pack bp-21 optional program cards architectural acoustics program card (tentative model name nx-28ba) (for measurement of sound pressure level differences between rooms, heavy fl oor i...

  • Page 152

    134 specifi cations sound level meter 1/3 octave band analyzer na-28 grp num menu slm rta ent cal light power + 1 2 start/stop store mode pause/cont - level 4 3 freq weight time 51 331 89 front view side view bottom view rear view rion unit: mm dimensional drawings.

  • Page 154

    No. 50490 06-08 printed in japan.