Specifications

ManualsBrandsOnset Computer ManualsData LoggersMX2306 HOBO MX Soil Moisture Data Logger, MX2307 HOBO MX Soil Moisture and Temperature Data Logger

HOBOMXSoilMoisture(MX2306) andMXSoilMoistureandTemperature(MX2307)DataLoggerManual

1‐508‐759‐9500(U.S.andInternational) 8 www.onsetcomp.com

1‐800‐LOGGERS(U.S.only) 

TrenchInstallationMethod

Thismethodisbestforshallowinstallationsatlessthan40cm

(15.7inches).Thisrequiresdiggingatrenchwithashovel,

excavator,orothertooltothedepthofthedeepestinstalled

sensor(ifinstallingmorethanoneinthemeasurement

location).Fordeepinstallations,thismayrequirealargetrench.

Thesensoristheninstalledcarefullybyhandintothe

undisturbedsoilofthetrenchsidewall.Thetrenchiscarefully

backfilledtopreservethebulkdensityofthesoilandavoid

dislodgingtheinstalledsensorbyaccidentallysnaggingthe

ferritecore.



SensorInstallationGuidelines

Beforeinstallingthesensor,followtheseguidelines:

 TestthesensorfunctionalityandaccuracyusingtheTEROS

verificationclip.Withthe verificationclipattached,the

readingsshouldbeintherangeof0.35to0.42m

.

RefertotheTEROSverificationclipdocumentationfor

moreinformation.Ifyoudonothaveaverificationclip,

youcanperformaroughcheckofsensorfunctionalityin

airandwater.Thesensorwillproducereadingsof~0.64

inwater(sensorfullysubmergedinwaterto1cm

upcable)andslightlynegativeinair. UseHOBOconnectto

exportorviewthedataforyourtest.

 Whencreatingtheholetoinstallthesensor,avoid

interferingobjects.Installationnearlargemetalobjects

canaffectthesensorfunction

anddistortreadings.Large

objectslikerootsorrockscouldpotentiallybendthe

needles.

 Thesensormaybepositionedinanydirection.However,

thereislessrestrictiontowaterflowwhenthesensor

bodyisplacedinaverticalpositionasshownbelow.A

verticalpositionwillalsointegratemore

soildepthinto

thesoilmoisturemeasurement.Installingthesensorwith

thesensorbodyinahorizontalpositionwillprovide

measurementsatamorediscreetdepth.



 Avoidanymetallocatedbetweenthesensorandthe

ferritecorebecauseitcaninterferewithVWC

measurements.

 Wheninstallingsensorsin

rockysoils,usecaretoavoid

bendingsensorneedles.

 Minimizeairgapsaroundthesensor.Airgapsaroundthe

sensorneedleswillresultinlowreadingsofsoilmoisture.

 Useconduittoprotectthecableagainstdamagefrom

animals,lawnmowers,exposuretochemicals,etc.

 Secureany

loosecableswithcableties.

SensorInstallationInstructions

1. Augerordigaholetothedesiredsensordepth.

2. Carefullyinsertthesensorintheholeandpushthesensor

sothattheneedlesareinsertedintotheundisturbedsideof

thesoil.Checkthatthesensorisfirmlyseated.

3. Ifusingthetemperaturesensorforsoil

temperature,insert

thatintothesideofthehole,atleast2cm(1inch)fromthe

soilmoisturesensorandferritecore.

4. Securethecable(s)andinstallconduitbeforebackfillingthe

hole.

5. Carefullyreturnthesoiltothehole,packingitbacktoits

nativebulkdensity.

Donothittheferritecoreasthiscould

pullthesensorfromthesoil.

6. IfusingtheMX2307loggerforairtemperature,asolar

radiationshieldisrequiredifthetemperaturesensorwillbe

insunlightatanytime.(SeeAccessories)

DeployingandMountingtheLogger

Followtheseguidelineswhendeployingthelogger:

 Mounttheloggersothesensorcableisnotbeingpulled.

Leaveabout5cm(2inches)ofdriploopinthecable

whereitcomesoutoftheloggertopreventwaterfrom

enteringtheloggerhousing.





 Usetheincludedlargescrewsorcabletiestomount

theloggerviathemountingholes.Usethescrewsto

attachtheloggertoawallorflatsurface.Usethe

cabletiestoaffixtheloggertoaPVCpipeormast.

ProtectingtheLogger

Note:Staticelectricitymaycausetheloggertostoplogging.

Theloggerhasbeentestedto8KV,butavoidelectrostatic

dischargebygroundingyourselftoprotectthelogger.Formore

information,searchfor“staticdischarge”ononsetcomp.com.

DripLoop