The Multifunction Extended Life (MEL) data logger uses precise time stamped data logging, microSD memory storage, real-time data access and USB connectivity. Available with a 16g or a 2g accelerometer sensor. The additional GPS option provides location data and precision GPS time synchronization. The MEL data logger operates as a standard USB mass storage device containing the comma delimited text data files and user setup files. The commercial standard “D” batteries (IEC R20) provides extended life operation suitable to long term data acquisition applications.Buy Online
MEL-x16 (16g Accelerometer)
MEL-x2 (2g Accelerometer)
For more details, specifications, and how to use the MEL, please refer to the user manual (.pdf). The user manual includes an example data file and instructions for converting the data and time stamps.
The MEL logger is configured using a simple text file called config.txt located on the microSD card. Below is an example config.txt file used for the MEL-x2+GPS:
; PRODUCT_ID = X2-GPS ; sync'd sample rates 1 to 16 in integer increments ; adxl355 sample rates 3.9, 7.8, 15.6, 31.2, 62.5, 125, 250, 500, 1000 SampleRate = 5 gain= low ; GPS PARAMETERS gpsOn = 1 ; minimum hdop required, in meters gps_MinLock = 40 ;gps_update interval, in seconds gps_sampleinterval = 1.000 ; used in on/off mode number of good samples to collect before turning off ; 10 samples = 10 seconds which ensures a GPS time sync gps_numSamples = 10 ; used in on/off mode, time in seconds device will spend trying to collect good samples ; allow 5 min to find GPS location gps_powerOnTime = 300 ; used in on/off mode, time, in seconds bewteen on events ; check GPS once per day gps_powerPeriod = 86400 ; discipline RTC with GPS time gps_clockThreshold = 0.010 ; dynamic models 0-->portable 2-->stationary 3-->pedestran 4--> automotive, 5-->sea, 6,7,8-->airborn gps_dynamicModel = 0 ; when enabled, polled mode saves power at the expense of timing accuracy gps_pollmode = 1 ;gps_gnssGlonass = 0x01010001 ; enable ; disable Glonass ;gps_gnssGlonass = 0x01010000 ; discard gps readings that exceed the minimum HDOP gps_nobad ; extra parameters to logger operation ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; FILE PARAMETERS ;set file length to 1 day samplesperfile = 86400 ; custom directory name ;dirname = /DATA ; custom file prefix filename = thz ; set timestamp to UTC seconds since Jan 1, 1970 instead of time since start of file absoluteTime ; EVENT DETECTOR PARAMETERS deadband = 0 DeadBandTimeout = 5 dwell=100 ;control brightness of LEDs, values are 'off' or 'high' statusindicators = high ;uncomment following line to activate logger upon disconnect from USB ;rebootOnDisconnect ; wakeupTime uses crontab format ; rtc alarm to wake up system ; wakeupTime = 5,35 wakes up system at 5 and 35 minute after the hour ; wakeupTime = 0,15,30,45 wakes up system ; wakeupTime = * wakes up system every minute ; wakeupTime = 0 2,8 wakes up system at 2 and 8 AM ;wakeupTime = 0,2,4,6,8,10,12,14,16 ; default secsToRecord is 0 , (off) ;secsToRecord = 60 ; logical, default is to remain turned on ;offOnEndRecord ;fileappend
Data is stored to simple text formatted .csv type files, which are easily imported into any spreadsheet or analysis software (Matlab, Octave, R, etc). Below is a example data file from the MEL-x16:
;Title, http://www.gcdataconcepts.com, X2-6, Analog Dev ADXL355, GPS ;Version, 2514, Build date, Jun 13 2023, SN:CCDC1021D5409E0 ;Start_time, 2007-01-01, 00:01:05.341 ;Uptime, 6,sec, Vbat, 2264, mv, EOL, 1800, mv ;Deadband, 0, counts ;DeadbandTimeout, 5.000,sec ;ADXL355, SR,1,Hz, Range, +/-2g, Hpf,off*Sr, Sens,256000,LSB/g (typ) ;BMP384, SI, 0.000,sec, Units, Pa, mdegC ;Alt Trigger disabled ;CAM_M8 Gps, SR,1,Hz ;Gps Sats, TOW, 1000, ver, 1, numSat, 0 ;, gnssId, svId, cno, elev, azmith, prRes, flags,inUse ;Time, Ax, Ay, Az, TOW, Lat,Lon, Height(m), MSL(m), hdop(m), vdop(m) 1167609852.002731,226096,-88115,46925 1167609853.002830,205622,-102666,12432 1167609854.002929,212564,-5637,-152842 1167609855.003028,208580,-58474,-140828 1167609856.003127,206656,-59723,-145012 1167609857.003226,204354,-64773,-146860 1167609858.003266,227116,-115432,-8197, 411730.000, 30.2957220,-89.3669477, -69.409,-41.922, 27.478,141.470 1167609859.003357,206295,6643,-164325 1167609860.003448,208722,3772,-156107 1167609861.003539,212280,2343,-148518 1167609862.003630,214120,3556,-147563 1167609863.003721,207400,-58019,-143397 1167609864.003812,208934,-61975,-139738 1167609865.003903,208370,-59809,-140637 1167609866.003937,227615,28,-122988, 411738.000, 30.2957194,-89.3668899, -65.174,-37.687, 25.038,119.888 1167609867.004020,227281,2598,-123695 1167609868.004103,226128,2574,-125831 1167609869.004186,226615,-1186,-124719