Extech Instruments LT40 Bedienungsanleitung

USERGUIDE

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WhiteLEDLightMeter

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ModelLT40

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LT40-EU-EN v1.3 9/13

Introduction

CongratulationsonyourpurchaseoftheExtechLT40LEDLightMeterthatmeasureslightfrom

whiteLEDlight,fluorescent,metalhalide,high‐pressuresodiumandincandescentsources.The

LT40canmeasurelightupto400,000Lux(40,000Fc).TheLT40offersanoverloadindication,low

batteryindication,Datahold,maximum/average/minimumhold(MAX/MIN),Zeroadjustment,

autopoweroffwithdisablefunction,andautorangingfeatures.Thisinstrument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

OverloadIndication:LCDscreenwillshow“OL”attheupperleft‐handcorner.

LowbatteryIndication””.

DisplayUpdateRate:2.5timespersecond.

SpectralresponsenearCIEluminousspectralefficiencyratings.

CosineAnglecorrected.

ConformstoJISC1609:1993andCNS5119generalclassASpecifications.

MeasuresLEDwhitelightandallvisiblelight.

MeasurestheintensityofilluminationinLuxorfoot‐candles.

Applicationsinclude:Warehouses,factories,officebuildings,restaurants,schools,library,

hospitals,photo/video,parkinggarages,museums,artgalleries,stadiums,building

security.

Dataholdfreezesdisplayedreading.

Maximum/Average/MinimumMemoryHold

Zeroadjustment.

Autopoweroffwithdisablefunction.

Autorange.

Safety

Donotoperatethemeterinenvironmentswherethefollowingarepresent:explosivegases

(ormaterials),combustiblegases(ormaterials),steam,ordust.

Pleasereplacethebatteryimmediatelywhenthesymbol“ ”appearsontheLCD.

Donottouchthemeter’scircuitboardforanyreasonasstaticelectricityorcontamination

coulddamagethesensitivecomponents.

ForIndooruseonly.Thisinstrumentwasdesignedforpollutiondegree2.

OperationAltitude:Upto2000m(7000’).

LT40-EU-EN v1.3 9/13

MeterDescription

1. Photodetector(removeprotectivecovertoexposesensor)

2. Display(LCD)

3. Controlpush‐buttons

4. PowerButton:ON/OFF

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Batterycompartmentandtripodmountarelocatedon

rearofinstrument

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Push‐ButtonDescription

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1. Lux/Fcunitsselector

2. CalibrationandZERObutton

3. Maximum/Average/Minimummemorybutton

4. Dataholdbutton

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LT40-EU-EN v1.3 9/13

Operation

PowerON‐OFF 

PressandholdthePowerbuttonforatleast2secondsandthenreleasetopowerthemeter.To

powerthemeterOFF,momentarilypressthePowerbutton.

TakingMeasurements

1. SwitchthemeterONandremovethesensor’sprotectivecovertoexposethelightsensor

dome.ThedisplayshouldswitchON,ifnotcheckthatbatteriesareinstalledandfresh.

2. Themetermeasurestheintensityofthelight(illuminance)thatstrikesthesensordomein

footcandlesandluxunits(1fc=10.76lux),displayingthismeasuredvalueonitsLCD.

3. Positionthemeterandlightsourcesothatthelightstrikesthesensordomestraighton

(perpendicular)withaslittleanangleaspossible.

4. Themeter’sdisplaycanshowavalueupto3999.However,forreadingsthatrepresent

measurementshigherthanthis,themeterusesx10feature(right‐mostdecimalpoint

flashing).Forexample,torepresentameasurementof39,999themeterwilldisplay3999

withtheright‐mostdigitflashing.

AutoPowerOFF

Tosavebatterylife,themeterpowersdownautomaticallyafterapproximately12minutesof

inactivity.

Enable/DisableAutoPowerOff

WhilethemeterisON,pressandholdthePowerbuttonforatleast2seconds(andthenrelease)

todisabletheAutoPowerOFFutility;theClocksymbolwillswitchOFF.ToenabletheAuto

PowerOFFutility,repeatthisprocess.

LUX/FCButton

PresstheLUX/FCbuttontotogglebetweenLuxandFC(foot‐candles)measurementunits.

LT40-EU-EN v1.3 9/13

MAX/MINButton

Themetercanrecordthemaximum,minimum,andaveragereadingsasdescribedbelow:

1. Momentarilypressthe“MAX/MIN”buttonandthemeterwillbegintotrackthe

maximum/average/minimummeasurements;the“MAX”iconwilldisplayatthetopofthe

LCDwindowindicatingthatthemeterisnowshowingthemaximumreading.Thereading

willnotchangeuntilahigherreadingisregistered.

2. Pressthe“MAX/MIN”buttonagaintoswitchfrom“MAX”to“AVG”,wherethemeterwill

showtheaveragemeasurementvalue.The“AVG”iconwillbedisplayedabovethedisplayed

value.

3. Pressthe“MAX/MIN”buttonagaintochangethemodefrom“AVG”to“MIN”,wherethe

meterwillshowtheminimumvaluemeasured.The“MIN”iconwillbedisplayed.

4. Pressthe“MAX/MIN”buttonagaintoswitchfrom“MIN”backto“MAX”.

5. Toexitthismode,holdthe“MAX/MIN”buttonforatleast2seconds.TheMAX/AVG/MIN

iconsshouldallbeswitchedOFFwhentheunitreturnstothenormaloperatingmode.

Data‘Hold’Button

PresstheHOLDbuttontofreezesthecurrentreadingontheLCD.PresstheHOLDbuttonagain

toreleasethereading.

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CALIBRATIONandZEROButtons

1000LUXCalibration

1. Preparea2856oK/1000Luxlightsourceandfacethemeter’ssensorperpendicularly

towardthelightsource.

2. Simultaneouslypressandholdboththe“CAL/ZERO”buttonandthepowerbuttonforat

least2seconds.

3. Releasethebuttonswhen“CAL”isdisplayedontheLCDscreen.

4. Pressandholdthe“CAL”buttonfor2moreseconds,andtheLT40willpowerdown.

5. Themeterisnowcalibrated.

ZEROCalibration

1. Ensurethattheprotectivecoverisattachedtothelightsensor.

2. PowerthemeterandtheLCDshoulddisplay‘0’.

3. Momenarilypressthe“ZERO”buttonforthezeroadjustmentandtheCALiconwill

switchON.

4. TheCALiconwillswitchOFFwhenthecalibrationhasbeencompleted.

5. IftheprotectivecapisnotcoveringthesensorwhentheZEOcalibrationisstartedthe

LCDdisplaywillread“CAP”.Inthiscase,pleasecoverthesensorwiththecapandrestart

thisprocedure.

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LT40-EU-EN v1.3 9/13

MeasurementConsiderationsandUserTips

Formaximumaccuracyallowthelightbeingmeasuredtofalldirectlyonthesensoras

perpendicularaspossiblewithaminimalangleofincidence.

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Whenthemeterisnotinusepleasekeeptheprotectivecapinplaceoverthelightsensor.

Thiswillprolongthelifeofthesensor.

Whenthemeteristobestoredforlongperiods,pleaseremovethebatteriesandstorethem

separately.Batteriescanleakandcausedamagetothemeter’scomponents.

Avoidareasofhightemperatureandhumiditywhenusingthisinstrument.

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BatteryReplacementandMaintenance

Cleaningandstorage

1. Thewhiteplasticsensordomeshouldbecleanedwithadampclothwhennecessary.Use

onlyamildsoapifneeded.Donotusesolvents,abrasives,orharshdetergentstocleanthe

dome.

2. Storethemeterinanareawithmoderatetemperatureandrelativehumidity.

BatteryReplacement

Whenthebatterypowerdecreasestoacriticallevel,thelowbatterysymbol“”willappearon

theLCD.Replacethe2x1.5VAAAbatterieslocatedintherearbatterycompartment.The

batterycompartmentslideseasilydownwardforremoval.Ensurethatthecompartmentcoveris

securelyfastenedbeforeusingthemeter.

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Neverdisposeofusedbatteriesorrechargeablebatteriesinhouseholdwaste.

Asconsumers,usersarelegallyrequiredtotakeusedbatteriestoappropriate

collectionsites,theretailstorewherethebatterieswerepurchased,orwherever

batteriesaresold.

Disposal:Donotdisposeofthisinstrumentinhouseholdwaste.Theuserisobligatedtotake

end‐of‐lifedevicestoadesignatedcollectionpointforthedisposalofelectricalandelectronic

equipment.

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BatterySafetyReminders

oPleasedisposeofbatteriesresponsibly;observelocal,state,nationalregulations.

oNeverdisposeofbatteriesinafire;batteriesmayexplodeorleak.

oNevermixbatterytypes;installnewbatteriesofthesametype.

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LT40-EU-EN v1.3 9/13

Specifications

Display4‐digitLCD(maximumdisplay:3999)withlowbatteryicon,

measurementoverload,andotherfunctionindicators

Sensor(detector)Siliconphotodiodewithspectralresponsefilterandcosine

correction

RangesandResolutionLux:399.9,3999,*39999,*399999

Foot‐candles:39.99,399.9,3999,*39999

*Readingsabove3999useax10orx100multiplier

(1Fc=10.76Lux)

Auto‐rangeThemeterautomaticallyrangesthedisplay

Accuracy±(3%ofreading+3digits)upto500Lux

±(3%)above500Lux

Calibratedtostandardincandescentlamp2856oKatan

ambienttemperatureof23oC

±8%forothervisiblelightsources

30±2%

60±6%

Angledeviationfromcosine

characteristics

80±25%

GeneralSpecifications

Samplingrate2.5timespersecond(digitaldisplay)

PhotodetectorSiliconphoto‐diodewithspectralresponsefilterandcosine

correction

OperatingconditionsTemperature:5to40oC(41to104oF);Humidity:<80%RH

StorageconditionsTemperature:‐10to60oC(14to140oF);Humidity:<70%RH

Lowbatteryindication“ ”appearsontheLCDwhenbatteryvoltagefallscriticallylow

LEDType WhiteLEDlightcanbeaccuratelymeasured

Powersupply2x1.5V‘AAA’batteries

BatterylifeApproximately200hours

AutoPowerOFFMeterswitchesOFFafter12minutesofinactivity

Dimensions133x48x23mm(5.2x1.9x1”)

Weight250g.(8.8oz.)includingbatteries

LT40-EU-EN v1.3 9/13

Appendices

TypicalLightLevels(1Fc=10.76Lux)

LuxFoot

Candles

LuxFoot

Candles



 Factories Home

20‐752‐7EmergencyStairs,Warehouse 100‐15010‐15Washing

75‐1507‐15Exit/EntrancePassages150‐20015‐20Recreational

Activities

150‐30015‐30PackingWork200‐30020‐30DrawingRoom,

Table

300‐75030‐75VisualWork:ProductionLine300‐50030‐50Makeup

750‐1,50075‐150Typesetting:InspectionWork500‐1,50050‐150Reading,Study

1,500‐3,000150‐300ElectronicAssembly,Drafting1,000‐2,000100‐200Sewing

 OfficeRestaurant

75‐1007‐10IndoorEmergencyStairs75‐1507‐15CorridorStairs

100‐20010‐20CorridorStairs150‐30015‐30Entrance,

WashRoom

200‐75020‐75Conference,

ReceptionRoom

300‐75030‐75CookingRoom,

DiningTable

750‐1,50075‐150ClericalWork750‐1,50075‐150ShowWindow

1,500‐2,000150‐2000Typing,Drafting

 StoreHospital

75‐1507‐15Indoors30‐753‐7EmergencyStairs

150‐20015‐20Corridor/Stairs75‐1007‐10Stairs

200‐30020‐30Reception100‐15010‐15SickRoom,

Warehouse

300‐50030‐50DisplayStand150‐20015‐20WaitingRoom

500‐75050‐75Elevator200‐75020‐75MedicalExamRoom

750‐1,50075‐150ShowWindow,

PackingTable

750‐1,50075‐150OperatingRoom

1,500‐3,000150‐300Storefront,ShowWindow5,000‐10,000 500‐1000EyeInspection



SpectralSensitivity

Peaksensitivitywavelength:550nm;

Deviationfromcomparativeluminosity

standard:JISstandardC1609‐1993.



Allrightsreservedincludingtherightofreproductioninwholeorinpartinanyform

www.extech.com 

RELATIVE SENSITIVITY (%)

WAVELENGTH (nm)

LT40

Andere Handbücher für LT40

Inhaltsverzeichnis

Andere Extech Instruments Multimeter Handbücher

Extech Instruments

Extech Instruments MM750W Bedienungsanleitung

Extech Instruments

Extech Instruments MultiLog ML720 Bedienungsanleitung

Extech Instruments

Extech Instruments EX411A Bedienungsanleitung

Extech Instruments

Extech Instruments EX540 Bedienungsanleitung

Extech Instruments

Extech Instruments 382860 Bedienungsanleitung

Extech Instruments

Extech Instruments DM4750D Bedienungsanleitung

Extech Instruments

Extech Instruments RC200 Bedienungsanleitung

Extech Instruments

Extech Instruments EX503 Bedienungsanleitung

Extech Instruments

Extech Instruments 382075 Bedienungsanleitung

Extech Instruments

Extech Instruments EX623 Bedienungsanleitung

Extech Instruments

Extech Instruments MN16A Bedienungsanleitung

Extech Instruments

Extech Instruments EX540-NIST Bedienungsanleitung

Extech Instruments

Extech Instruments MiniTec Series Bedienungsanleitung

Extech Instruments

Extech Instruments SDL350 Bedienungsanleitung

Extech Instruments

Extech Instruments 407910 Bedienungsanleitung

Extech Instruments

Extech Instruments 407119A Bedienungsanleitung

Extech Instruments

Extech Instruments EX360 Bedienungsanleitung

Extech Instruments

Extech Instruments 380942 Bedienungsanleitung

Extech Instruments

Extech Instruments 407119A Bedienungsanleitung

Extech Instruments

Extech Instruments EX210 Bedienungsanleitung

Extech Instruments

Extech Instruments MultiTec MT310 Bedienungsanleitung

Extech Instruments

Extech Instruments 45170CM Bedienungsanleitung

Extech Instruments

Extech Instruments MultiMaster MM560 Bedienungsanleitung

Extech Instruments

Extech Instruments 430 Bedienungsanleitung

Beliebte Multimeter Handbücher anderer Marken

Agilent Technologies

Agilent Technologies 34420A Bedienungsanleitung

Fluke

Fluke 83 Bedienungsanleitung

Hameg

Hameg HM 8012 Bedienungsanleitung

Mastech

Mastech MY70 Bedienungsanleitung

Steren

Steren MUL-300 Bedienungsanleitung

Somogyi Elektronic

Somogyi Elektronic home SMA 92 Bedienungsanleitung

Gossen MetraWatt

Gossen MetraWatt METRAmax 6 Bedienungsanleitung

PeakTech

PeakTech 4000 Gebrauchs- und Pflegehandbuch

YOKOGAWA

YOKOGAWA 90050B Bedienungsanleitung

Gossen MetraWatt

Gossen MetraWatt METRALINE DMM16 Bedienungsanleitung

Fluke

Fluke 8846A Bedienungs- und Wartungshandbuch

Tempo Communications

Tempo Communications MM200 Bedienungsanleitung

Elenco Electronics

Elenco Electronics CM-1555 Bedienungsanleitung

Mastech

Mastech MS8238C Bedienungsanleitung

SDAR

SDAR 830A, 830B, 830D, 830C Bedienungsanleitung

RS PRO

RS PRO RS-9519BT Bedienungsanleitung

BGS technic

BGS technic 8890 Bedienungsanleitung

Amprobe

Amprobe Hexagon 60 Bedienungsanleitung