Extech Instruments LT40 Manuale utente

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

Altri manuali per LT40

Indice

Altri manuali Extech Instruments Multimetro

Extech Instruments

Extech Instruments MN62 Manuale utente

Extech Instruments

Extech Instruments CMM-17 Manuale utente

Extech Instruments

Extech Instruments MultiPro MP510 Manuale utente

Extech Instruments

Extech Instruments EX310 Manuale utente

Extech Instruments

Extech Instruments EX520 Manuale utente

Extech Instruments

Extech Instruments Extech 470 Manuale utente

Extech Instruments

Extech Instruments SDL900 Manuale utente

Extech Instruments

Extech Instruments MiniAmp Series Manuale utente

Extech Instruments

Extech Instruments 38073A Manuale utente

Extech Instruments

Extech Instruments EX310 Manuale utente

Extech Instruments

Extech Instruments MiniTec Series Manuale utente

Extech Instruments

Extech Instruments EX470A Manuale utente

Extech Instruments

Extech Instruments MultiTec MT310 Manuale utente

Extech Instruments

Extech Instruments EX505-K Manuale utente

Extech Instruments

Extech Instruments 382065 Manuale utente

Extech Instruments

Extech Instruments 430 Manuale utente

Extech Instruments

Extech Instruments 45170CM Manuale utente

Extech Instruments

Extech Instruments MO290 Manuale utente

Extech Instruments

Extech Instruments EX430A Manuale utente

Extech Instruments

Extech Instruments EX350 Manuale utente

Extech Instruments

Extech Instruments EX540-NIST Manuale utente

Extech Instruments

Extech Instruments MN15A Manuale utente

Extech Instruments

Extech Instruments EX430-NIST Manuale utente

Extech Instruments

Extech Instruments MA220 Manuale utente

Manuali Multimetro popolari di altre marche

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Agilent Technologies 34420A Manuale utente

Fluke

Fluke 83 Manuale utente

Hameg

Hameg HM 8012 Manuale utente

Mastech

Mastech MY70 Manuale utente

Steren

Steren MUL-300 Manuale utente

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Somogyi Elektronic home SMA 92 Manuale utente

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Gossen MetraWatt METRAmax 6 Manuale utente

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PeakTech 4000 Manuale per l'uso e la cura

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YOKOGAWA 90050B Manuale utente

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Gossen MetraWatt METRALINE DMM16 Manuale utente

Fluke

Fluke 8846A Manuale operativo e di manutenzione

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Tempo Communications MM200 Manuale utente

Elenco Electronics

Elenco Electronics CM-1555 Manuale utente

Mastech

Mastech MS8238C Manuale utente

SDAR

SDAR 830A, 830B, 830D, 830C Manuale utente

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RS PRO RS-9519BT Manuale utente

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BGS technic 8890 Manuale utente

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