AudioQuest M-27 manual

TABLE OF CONTENTS INTRODUCTION………………………………………… …………………………………………….3 M-27 SIMPLIFIED OPERATING INSTRUCTIONS…………………………….…………… ……..5 Control Keys……………………………………… …………………………………..……..5 Sound Leve[...]

FCC COMPLIANCE AND CAUTIONARY NOTE: User is cautioned that chang es or modifications not expressly appr oved by the party responsible fo r compliance could void the user's authority to operate the equipment. NOTE: This equipment has been tested and found to comply with the limits for a class B digital device, pursuant to part 15 of the FCC Rul[...]

Events Monitor: Accumulates the following data for up to 16 separate events: 3 separate integrated sound levels. 3 separate noise doses. 2 time weight ed average s and a sound expo sure leve l. Peak level, maximum level, start time, and run time. The M-27 as an overall unit accumulates data for: 3 separate dosimet ers. 3 separate 1 minut e time his[...]

In steps 1 to 3 only data for the HTL ( High Threshold Level ), LTL (Low Thres hold Level), or 3 dB (No Thresh-old) will he displa yed or pr inted. In step 4 data for HTL, LTL, and 3 dB will be printed. Step 5 dumps raw data to the Computer. Step 6 reads or resets the Clock. Step 7 reads or stores the Calibrator level. Sound Level Meter Keys SOUND [...]

L-AVG The average or equivalent l evel for the HTL, LTL, or LEQ 3 dB for the event. DOSE The percent Dose f or the HTL, LTL, or 3 dB for the event. TWA The Time Weighted Average for HTL or LTL or the SEL Sound Exposure Level for the event. PEAK The Peak Level for the event. LEVEL MAX The Maximum Level for the event. LEVEL RUN The Run Time of the ev[...]

Dumping Raw Data The data stored in the unit may be transferred to a computer or printer for reprocessing. Thi s data is useful only with additional comput er programs. Consult Quest for programs. CODE Press key until CPU is displayed. HL3 PRINT Prints raw data to computer. ON Stops printout. OFF Changing Printer Parameters Internal switch 3 contai[...]

Battery Indicator: 8-hour battery life, 1 week data retention Calibrator: External calibrat or Temperature: -15° to 50°C operating; -40° to 60°C storage (battery removed). Humidity: 0 to 95% non-c ondensing Magnetic Field Effects: Negligible below 50 Oersteds at 50 to 60 Hz Size: 5 ½ x 2 ¾ x 1 3/8 i nches (140 x 70 x 40 mm) Weight: 14 ounce s[...]

It also has a 1 second Slow and a.125 second Fast time cons tant circuit. Present OSHA requirements specify Slow. Microcomputer Modes The M-27 is contr olled by a MC1468 05 CMOS Microc omputer. The sy stem has 8192 byt es of RAM, 6144 byte s of ROM, a 33-segm ent LCD, 24 pr ogramming swit ches, serial and pa rallel printer outputs, a V/F converte r[...]

Where: LS = Sound level in dB with slow time constant if the sound level is greater than the threshold level and is - ∞ if the level is less than the threshold level. L3 = Sound level in dB without slow time constant. TC = Criterion time in seconds or 28800 seconds. RTIME = Run time in seconds. ER = Exchange rate in dB. CRIT = Criterion level in [...]

NOTE When the unit is off, the battery still powers the memory. If the unit is not going to be used for a few day s, the battery shoul d be removed. Microphone Replacement The microphone is field replaceable. To unscrew th e microphone, grip the knurled nut on the top of the dosimeter and gently turn it counterclockwise. Do not twist or turn the co[...]

6. Attach the microphone to the collar or shoulder of the op erator (see Effects of Operator Presence and Figure 6). 7. Press the RUN key and hold until you see the unit cou nt. 8. Install the security cover and attach the unit to the operato r's belt or pocket. 9. At the end of t he workday, remove t he security cover an d press PAUSE. 10. Re[...]

6. Move to the ne xt area and repeat steps 4 a nd 5. 7. When finis hed with surve y or when 16 events are accumulated, press ON/OFF to exi t EVENTS. At any time, even when accumulating data, th e cu rrent or any pre vious event data m ay be displayed. Press EVENT key until the desired event is displayed . Press any other key to display data for tha[...]

Parallel Printers Check printer manual to set up printer. If switches are changed it may be necessary to reset the printer. Check interconnecting cable to as sure it is the proper cable. Set the internal switches in the M-27 to agree with the printer. It is not necessary to reset the M-27 if switches are changed. Connections to Printer 1. Make sure[...]

NOTE If the level is less than the threshold for part of the minute the average can be less than the threshold. If no levels above the threshold level are measured, the level is set to 00 dB. The first + in the gra ph is 50 dB and the next is 60 dB , etc. Each - is 2 dB. 105 dB is the avera ge of the 5 levels c ombined with a 5 dB exchange rate. Ea[...]

. .61 is the percent dose accumulated at 80 dB. 1.23 is the perc ent at 81 dB, etc. The percent dose statistical distribution is accumulated without a threshold . Of course, the dose calculations in the summary exclude any dose accumulated below the threshold. The graph is similar to the % TIME graph. If the internal TEXT or GRAPH switch is off, th[...]

and prints only that data. As an example, if HIST 5 has been p ressed, pressing PRINT will print out a heading, a summary, a 5-mi nute histog ram, and a statistical distribution. If HTL is annunciated, pressing HIST 10 will print a 10-minute histogram for the high threshold level only. It is possible to change the printout while it is printing by p[...]

Printer Setup Serial Printer Output The serial printer output is RS-232-C compatible. It sends data in ASCII cod e at 300, 600, 1200, or 2400 Baud. The data is sent asynchronously. The Data Set Ready line is checked before sendi ng a character. Each character consists of 11 bits made up of a sta rt bit, 8 ASCII character bits, and 2 st op bits. Eac[...]

he M-27 may draw addi tional curr ent when connected to a printer. For best results connect the M- 27 to a printer on ly when printing data. INTERNAL SWITCHES The M-27 is set at the factory to the c urrent OSHA re quirements unle ss otherwise specifi ed. When the CODE key is pressed, the display shows a coded di splay o f the current internal switc[...]

Switch Positions Switch 1 and 2 sel ect the M-27 functio ns. Switch 1 and 2 are read only on RESE T and when the battery is replaced. Switch 3 selects printer options. Switch 3 is read at the start of each printout and may be changed without destroying data . SWITCH 1 Position 1 On = "C" weighting Off = "A" Position 2 On = 30 dB[...]

Position 3 On = Print Graphs Off == No Graphs Position 4 On = Print Text Off = No Text If 3 and 4 are both off, Graphs will print. Positions 5 6 2nd and Last print character in HEX On On = 0A 0D L F CR Off On = 0A 00 LF On Off = 0D 0A CR LF Off Off = 00 0D CR Positions 7 8 Baud Rate On On = 300 baud On Off = 600 baud Off On = 1200 baud Off Of f = 2[...]

To set the criterion level to 80 dB and the exchange rate to 3 dB, set the next 4 positions down. For a high threshold of 80 and a low threshold of 70 set the first 4 positions of the right switch to down, up, up, and up. To identify this unit as unit 0 set the next three switches down. (If the unit number is set to zero the code will not show the [...]

For the 3-digit code: 1. Press CODE/HL3 until 3 or less digits code are displayed. (Leading zeros are not displayed.) 2. Enter code i n table. 3. Convert Hex t o binary (see Tabl e 1). 4. Look up each position in inter nal switch section. 3 decodes to unit 3. F decodes to parallel printer with graph and text. C decodes to 0A a nd 00 print endi ng a[...]

between TWA and Dose is that TWA is expressed in decibels and Dose is expressed as a perce nt. TWA is equal to a c ontinuous level w hich if constant f or eight hours would produce the same noise dose as the do se accumulated over t he run time . The average integrated sound level (La vg) will be equal to TWA at eight hours. If the time is less tha[...]

it is turned on, is reset, or the PAUSE key is pr essed. Wait until the sound lev el has stabilized before entering the run m ode. Always remember to press RUN. Press PAUSE before pressing PRINT. If in the ru n mode, the data printed at the beginning of the printout will not agree with the data at the end. Considerations of Measurement and Accuracy[...]

Service Policy The Quest product you have purchased is one of the finest ac oustic instruments available. It is backed by our full one ye ar warranty which seeks complete customer satisfaction. This is your assu rance that you can expect prompt courteous service for your equipment from the entire Quest service organization. Should your Quest equipm[...]