Kewtech KTD40 User manual

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www.kewtechcorp.com
KTD40
Multifunction Digital
Loop Impedance Tester
User Manual

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Caution
Before using your KTD40 please read these instructions; in particular note the safety
issues that follow:
• Althoughfullyprotectedupto440VACthistesterisforuseon230VACcircuits
only.
• Alwayscheckthetesteronaknown,correctlywired,livesocketoutletbeforeand
after use.
• Beforeusecheckyourtesterforanydamagetotheplug,leadandcabinet.
Important calibration/check box note
• BecauseoftheSuperSmartLoopTestSystemthetestisimmunetosuddenvalue
changes(suchasvoltagespikes).
• Asaresultwhenchangingcalibrationorcheckboxloopvaluestheunitmustbe
switchedoffbetweenchanges.
BSEN61010-1
AtKewtechourengineersconstantlylookforimprovement.Ifthereisanyaspectof
yourKewtechtesteryouwouldliketocommentonpleasevisitourwebsiteat
Kewtechcorp.com
Operation Overview
Your Kewtech tester has a special polarity test function.
ItisalittleknownfactthatasystemcanbereversewiredwithLine(Phase)toearth/
neutralandearth/neutraltoLine(Phase).Thesocketswillallworkandconventionalloop
testerswillshowandtestthateverythingiscorrectdespitethisverydangerouswiring
condition.
Althoughextremelyrare,thismiswireconditioncanexistsoifyourtestshowsthisfault
donotproceed–ifinanydoubtadviseyourcustomertocontacttheirsupplycompany
immediately.(Seeteststep 3,page9)
CORRECT POLARITY
Correct polarity
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Operation overview
Your Socket & See tester has a special polarity test function.
It is a little known fact that a system can be reverse wired with Live (Phase) to
earth/neutral and earth/neutral to Live (Phase) The sockets will all work and
conventional loop testers will show and test that everything is correct despite
this very dangerous wiring condition.
Although extremely rare, this miswire condition can exist so if your test shows
this fault do not proceed – if in any doubt advise your customer to contact their
supply company immediately. (See test step 3, page 9)
FUSE 100A
From supply
company
LIVE (Phase)
NEUTRAL
Ty pical supply service
cut-out fuse
Live (Phase)
to meter
Neutral to meter
To main earthing
terminal
Solid brass
connecting block
FUSE 100A
From supply
company
NEUTRAL
LIVE (Phase)
Ty pical supply service
cut-out fuse
Neutral to meter
Live (Phase)
to meter
To main earthing
terminal
Solid brass
connecting block
REVERSE POLARIT Y
REVERSE POLARITY
LINE (Phase)
LINE (Phase)
NEUTRAL
NEUTRAL
LINE (Phase)
to meter
LINE (Phase)
to meter
To main earthing
terminal
Neutral to meter
To main earthing
terminal
The Kewtech KTD40 Loop Impedence Tester is designed for use by suitably
qualified personnel familiar with electrical supply systems.

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Operation overview
TheKTD40willtestforNo-triploop,HighcurrentTrueLoopImpedance,No-tripPFC/
PSC(ProspectiveFaultCurrent),HighcurrentPSCusingTrueLoopImpedance,mains
voltage(L-N,L-EandN-E)andcorrectsocketwiring,inadditiontotheincomingsupply
polaritycheckdescribedonthepreviouspage.
AnotheruniquefeatureofyourKTD40testeristhehighcurrent2-wiremeasurementof
theTLI(TrueLoopImpedance).Regulationsandguidancebooksrefertoloopimpedance
measurementsbutupuntilnowlooptestersmeasuredloopresistancewhichisdifferent
fromloopimpedance,particularlywhentestingclosetothemainsupplytransformer.
Thisfunctionisthereforerecommendedwhentestingforexternalearthfaultloop
impedance(Ze)atdistributionboardsonnonTTsystemsandsimilarpointsonthe
supplysideofanySwitch/RCDgearandwhentestingtheLine/Neutrallooptodetermine
prospectiveshortcircuitcurrent.
ItisthevariationinpowerfactorthatmakestheTLImeasurementofyourKTD40so
muchmoreaccuratethanolderlooptestingtechniques.(Becauseofthistheremaywell
bevariationsinreadingscomparedtoordinarylooptestersortheno-tripfunctionofthis
tester,particularlywhenthemeasurementismadeneartothemainsupplytransformer).
TheKTD40alsohasaNo-triptestmodethatisguaranteednottotripa30mAorhigher
ratedRCDprovidingthatthecircuitisotherwisehealthy.
No-trip vs High current testing
AlthoughtheKTD40HighcurrentTLImeasurementmodeisinherentlymoreaccurate
thanconventionaltechniqueswhenmeasuringclosetothemainsupplytransformer,the
differencebetweenresistanceandtrueimpedancereducesthefurtherawayfromthe
transformer the measurement is made.
ThisiswhyusingtheNo-tripmodeissuitableformeasurementonnalcircuitsand
similarlyremotepoints.ItshouldbenotedhoweverthatwhilstNo-triptestingatthese
locationswillnormallyfunctionatasimilarhighlevelofaccuracy,thelowcurrent
measurementtechniqueusedismorelikelytobeadverselyaffectedbyexternalfactors
suchascontactresistance(e.g.whentestingatseldomusedsocketoutlets)andcircuit
noise(e.g.switchedmodepowersupplyonthesamecircuit).Thiscanresultinthe
occasional erroneous reading.
Forthisreasonitisrecommendedthatmultiplemeasurementsaremadewhenusingthe
No-tripmodeandanyisolatedoddresultsareignored.Whentakingmultiplereadingsthe
testerorthesupplyshouldbepoweredoffbetweenconsecutivetests.Wherepractical
otherequipmentpoweredbythesamesocketshouldbeturnedoff.
ForsafetyreasonsNo-tripmodeisrecommendedforallmeasurementsmadeonTT
systems.
Test lead configuration
Important
TheKTD40canbeusedwith2differenttypesofconnectinglead.Itisimportantto
understandandusethecorrectleadcongurationforeachtestmodeoryoumaynot
obtainthecorrectresults.
Leadoptions
1 Ref:KAMP13 Themainslead(IECC13to13Aplug)typeconnectorthatis
supplied with the tester.
2 Ref:ACC016E The3-Polefuseddistributionboardtestleadsetwhichterminates
infusedprods/crocodileclips.Thisissuppliedasaseparateaccessorytothe
KTD40.
Theleadisanintegralpartofthetesterset-upandshouldaccompanythetesterwhen
beingreturnedforre-calibrationorservice.Donotuseanyothertypeofmainsleador
fusedtestleadsetasitwouldbelikelytogiveincorrectresults.
Lead configuration for No-trip testing
This is the default mode that the KTD40 will start in when turned on. This mode is most
usefulfortestingatsocketoutlets,luminaires,wiringterminals,etc.ininstallations
wherethecircuitundertestmaybeprotectedbyanRCD.
InNo-tripmodethetestercanbeusedwiththemainsleadwhentestingat13Asocket
outlets,orthedistributionboardleadsetfortestingatotherpointsinthecircuit.
WhentestingwiththeKTD40inNo-tripmodethe3colourcodedprods/crocodileclips
ofthetestleadshouldbeconnectedtothecorrespondingLine,NeutralandEarth
terminals.
Thismodecanbere-selectedatanytimebypressingbutton5labelled‘No-trip’.

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Test lead configuration
Lead configuration for High Current 2-wire testing with TLI feature
TheTLI(TrueLoopImpedence)functionisintendedforuseatdistributionboardsand
similarpointswhereyouaremeasuringonthesupplysideofanySwitch/RCDgear.
TheTLImeasurementfunctionisselectedbypressingbutton9labelled‘Ze/DB’.This
functionusesthemaximumhighcurrentofthetesterandrequirestheuseofthe
distributionboardleadsetconguredin2-wiremode.Donotusethisfunctionwiththe
mainsleadorthedistributionleadsetin3-wiremode.
Toarrangethetestleadsin2-wiremodepulltheblueprodoffthebluetestleadand
plugtheexposed4mmconnectorintothebackofthegreenconnectorasshownbelow.
YouwillnowhavetheEarthandNeutralleadsconnectedtogetherreadyforconnection
totheEarthorNeutralconductortobetested.
Operation – a Detailed View of the KTD40
2 ThreeLEDsshow
socket wiring
status
4 LCD-default
L-Nvoltage
measurement
1 On/Offbutton
5 No-triploopselect
(default)
7 No-tripPFC
(prospectivefault
current)
6 Pushtostarttest
9 Highcurrent
loop impedance
test
8 Voltageselect
L-N(default)L-E
andN-E
3 PolarityTest
10 Highcurrent
PFCtest

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Overview of the Display
A Loopreadingselected(Ω)
B PFC/PSCprospectivefaultcurrent/prospectiveshort 
 circuitcurrentreadingselected(A/kA)
C Looptestmodeselected–notrip(default)orHi-I(highcurrent)
D HANDSFREEoperation
E Ohmssymbol
F Volts(AC)
G VoltagemeasurementfunctionL-N(default)L-EandN-E
H Faultcurrent
I Wait–resultcalculationinprogress
J Wait–testerhasgoneoveroperatingtemperature
K BatteryCondition(=good)
L Greaterthan(>)lessthan(<)indication
Loop-PFC/PSC Testing
1 PowerON/OFF–PressingthisbuttonturnstheKTD40onandpressingagainturns
theunitoff.Intelligentautopower-offoccursafter3minutesofinactivity,butfor
safety the instrument stays powered if it is displaying a socket wiring fault.
2 WhentheKTD40isrstconnectedtoalivesocketitwillautomaticallytest
thesocketwiringtoestablishthatthecircuitwireshavebeenconnectedtothe
correctterminalsonthebackofthesocket.IfallthreeLEDslightGREENandno
sound is emitted the wiring status is correct and you can proceed to the incoming
supplypolaritytest(step3).
 Afaultwiththesocketwiringwillbeindicatedbyanaudiblealternatingtoneand
theLEDs,atleastoneofwhichwillberedororange,willash.Ifafaultindication
isgiven–DONOTPROCEED–investigationandremedialactionisrequiredbefore
you can conduct a loop test.
 Ifthishappensplacingyourthumbonthegreycolouredpolaritytestpadwillnow
activatethe‘faultlocation’function.Withyourthumbrmlyonthepadcheckthe
indicationgivenbytheLEDsagainstthechartonthebackcovertoidentifywhere
themainproblemlies.
Note: ThecolouroftheLEDsmaychangewhenthepadistouched.
3 IncomingsupplyPolarityTest–thisimportanttestisdiscussedinfullon
page3ofthismanual,pleaseread.
 ToconductthetestwithallthreeLEDslitGREENplaceyourthumbonthegrey
colouredpolaritytestpadarea.Ifthesupplypolarityiscorrecttherewillbeno
changeinindicationandyoucanproceedtostep4.Ifthesupplypolarityhasbeen
reversedthethreeLEDswillturnredandash.
 Ifthishappensstoptestingandnotifythesupplycompanyimmediately.
4 Checkthatthemainsvoltageisinthecorrectrange207–253VAC.
Note: Alltestsareinhibiteduntilthemainsvoltageappearsinthedisplay.
5 NO-TRIP Yourtesterdefaultstono-triplooptestingwhenyourstswitchon–
buttonvere-selectsno-triplooptestifyouhaveselectedotherfunctions.
6 TEST Abriefpressofthetestbuttonwillinitiatethelooptestandafterafew
secondstheresultwillbedisplayed(Important:seenotesonpage4).
 TheKTD40alsohasaHANDSFREEtestfunctionthatisactivatedbypressingthe
testbuttonbeforeconnectingtothemainssupply.Thisisveryusefulfortestingat
luminairesorsimilarconnectingstripswhenyourhandsareoccupiedbyholding
thetestprobes.

LOOPPFC –PSC HANDSFREE
WAIT
NO-TRIPH I - I
K
J
H
C
E
B
kA
VLE
NE
A D
F
H
LG
I
PRESS AND HOLD
Ω

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Loop-PFC/PSC Testing - continued
WhenusingHANDSFREEmodewiththedistributionboardtestleadsetalways
connecttheEarthandNeutralpolesbeforetheLine,otherwiseitwillindicatea
polarityfaultandinhibitfurthertesting.
HANDSFREE testing in No-trip mode.
The tester will automatically conduct the socket wiring test upon connection to the
Livesupply.IfalliswellitwillimmediatelyinitiateaLooptest.
Whenthetestiscompletetheresultwillbedisplayedforafewsecondsbeforethe
displayrevertstoshowingtheL-Nvoltage.
TheLooptestresultcanberecalledbypressingtheNo-tripbuttonandthePFC/
PSCresultcanberecalledbypressingtheNo-tripPFCbutton.
7NO TRIP PFC HavingcarriedoutaNo-tripEarthfaultlooptest–pressingthis
buttoncalculatesthePFC(ProspectiveFaultCurrent)bydividingthemeasuredloop
resultintothemeasuredL-Evoltage.
8 VOLTAGE ThedefaultvoltagemeasurementismadebetweenL-N.Usingthis
buttonyoucanoverridetomeasureL-Eandasanalsafetycheckmeasurethe
N-Evoltagepresent.
9 Ze/DB ThisbuttonselectstheHighCurrentTrueLoopImpedancemode.Useonly
withthetestleadsetconguredfor2-wiremode(seepage6).
 Connectthetestleadstothetwoconductorsbeingtested.Thesupplyvoltage
(seestep8)willbedisplayed.AbriefpressofthetestbuttonwillconducttheLoop
testandtheresultwillbedisplayedalmostimmediately.
Note: In2-wiremodethevoltagedisplayedwillbethatmeasuredacrossthe2
conductorsthatthetestleadsareconnectedto.ThedisplaywillshowthisasL-N
regardlessofwhethertheyareconnectedacrossL-NorL-E.
HANDSFREE testing in High current 2-wire mode.
Thisfunctionisparticularlyusefulfortestingatdistributionboardsandisactivated
bypressingthetestbuttonbeforeconnectingtothemainssupply.TheKTD40
willthenautomaticallyconductaLooptestuponconnectiontothelivesupply
anddisplaytheresult.ThesupplyvoltagecanberecalledbypressingtheVoltage
buttonandthePFC/PSCresultcanberecalledbypressingtheNo-tripPFCbutton.
10 PFC/PSC ProspectiveFaultCurrent/ProspectiveShortCircuitCurrent.Pushing
thisbuttondividestheaboveTLI(TrueLoopImpedance)resultintothevoltage
measuredbetweenthetwopointsundertesttogiveeithertheprospectiveshort-
circuitcurrent(whenL-Nistested)ortheprospectiveearthfaultcurrent(whenL-E
istested).
Specifications
Wiring Test
DetectsmissingEorN(>15kΩ)
DetectsL-EorL-Nswap
DetectsLive–Earth/NeutralreversalbyuseofPolarityTestPad
Phase–Neutralvoltagemeasurement ±1%±1V
Phase–Earthvoltagemeasurement ±1%±1V
Neutral–Earthvoltagemeasurement ±1%±1V
Loop Test
Notripmode3wiretestingPhase–Neutral–Earthallconnected
Testcurrent<15mAat253VAC
Range Accuracy
0.00to9.99Ω ±5%±5digits
10.00to99.9Ω ±3%±3digits
100.00to500Ω ±3%±3digits
Highcurrentmode2wiretestingPhase-NeutralorPhase-Earthconnectedusingtrue
impedancemeasurement–autotest(handsfree)isselectable.
Range Accuracy
0.00to9.99Ω ±3%±3digits
PFC/PSC Measurement
10A–19.9kA Thisisacalculatedresultusingthelooptestmeasurementbut
  itwillbeinherentlymoreaccuratethantraditionalmethodsas
the test is of impedance not solely resistance.
Over Voltage Protection
440VAC  Nodamage–completerecovery
Power
4×AAbatteries(notincluded)
Batterylife(BSEN61557)>10,000test(orshelflifeofbatteriesinstalled)
Environmental
OperatingTemperatureRange 0°Cto40°C
StorageTemperatureRange –10°Cto+60°C
OperatingHumidity 93%RH@40°C
Size 157mm×89mm×39mm
Weight 400g

12
www.kewtechcorp.com
Kewtech Corporation Limited
MidasHouse,Unit2b,StonesCourtyard,HighStreet,Chesham,BucksHP51DE
T: 01494 792 212
F:01494791826
E:[email protected]
Condition Wiring Supply LED Buzzer
Number Condition Terminal Display
N E L
Socket Wiring
1 Correct N E L Continuous
2 L-E reverse N L E Warble
3 L-N-E miswire E L N Warble
4 L-N reverse L E N Warble
5 L-N-E miswire L N E Warble
6 Faulty N / L-E miswire NC L N Warble
7 Faulty N / E miswire NC N L Warble
8 Faulty N NC E L Warble
9 Faulty N / L-E reverse NC L E Warble
10 Faulty E / L-N reverse L NC N Warble
11 Faulty E N NC L Warble
12 Faulty E / N miswire E NC L Warble
13 Faulty E / L-N miswire L NC E Warble
14 Faulty L / N-E miswire L N NC Warble
15 Faulty L / E miswire N L NC Warble
16 Faulty L / N-E miswire E L NC Warble
17 Faulty L / N miswire L E NC Warble
18 No Mains NC NC NC None
Above is the indication given when touching the touch pad.
LEDs will flash to indicate fault condition NC = No Connection