AEMC 6240 User manual
MICRO-OHMMETER 6240
ENGLISH User Manual
Statement of Compliance
Chauvin Arnoux®, Inc. d.b.a. AEMC®Instruments
certifies that this instrument has been calibrated
using standards and instruments traceable to
international standards.
We guarantee that at the time of shipping your
instrument has met its published specifications.
An NIST traceable certificate may be
requested at the time of purchase, or obtained
by returning the instrument to our repair and
calibration facility, for a nominal charge.
The recommended calibration interval for this
instrument is 12 months and begins on the date of
receipt by the customer. For recalibration, please
use our calibration services. Refer to our repair
and calibration section at www.aemc.com.
Serial #: ________________________________
Catalog #: 2129.80
Model #: 6240
Please fill in the appropriate date as indicated:
Date Received: _________________________________
Date Calibration Due: _______________________
Chauvin Arnoux®, Inc.
d.b.a AEMC®Instruments
www.aemc.com
Table of Contents
1. INTRODUCTION............................................................................... 3
1.1 International Electrical Symbols................................................4
1.2 DenitionofMeasurementCategories .....................................4
1.3 ReceivingYourShipment..........................................................4
1.4 OrderingInformation.................................................................5
1.4.1 AccessoriesandReplacementParts............................5
2. PRODUCT FEATURES ...................................................................... 6
2.1 Description................................................................................6
2.2 Applications ..............................................................................7
2.3 KeyFeatures ............................................................................7
2.4 ControlFeatures .......................................................................8
2.5 ButtonFunctions.......................................................................9
2.6 DisplaySymbols .....................................................................10
3. SPECIFICATIONS........................................................................... 11
3.1 Electrical .................................................................................11
3.2 Mechanical..............................................................................12
3.3 Environmental.........................................................................13
3.4 Safety......................................................................................13
4. OPERATION .................................................................................. 14
4.1 PrecautionsBeforeUse..........................................................14
4.2 InstrumentConguration(SET-UPmode) ..............................14
4.3 ResistanceMeasurements .....................................................15
4.3.1 MeasurementReadings..............................................16
4.3.2 ConnectionsandReadings.........................................16
4.3.3 Test Lead Connection .................................................17
4.4 RepetitiveMeasurements .......................................................17
4.5 MeasuringVeryLowResistance ............................................18
4.6 AutomaticRecording ..............................................................19
4.7 StoringResultsintoMemory...................................................20
2
Micro-Ohmmeter Model 6240
4.8 RecallingResultsfromMemory..............................................21
4.9 ErasingMeasurementsfromMemory.....................................22
4.9.1 ErasingSelectedMeasurements................................22
4.9.2 ErasingAllMeasurements ..........................................22
5. DATAVIEW®SOFTWARE ................................................................ 23
5.1 Introduction .............................................................................23
5.2 InstallingDataView®................................................................23
5.3 ConnectingtheInstrumenttoyourComputer.........................27
5.4 OpeningtheMicro-ohmmeterControlPanel ..........................28
5.5 ConguringtheInstrument .....................................................29
5.6 DownloadingStoredTests ......................................................30
5.7 Saving/ExportingDatatoaSpreadsheetorPDFFile ............31
5.7.1 SavingDatatoaSpreadsheet....................................31
5.7.2 ExportingDatatoaPDFfromDataView®...................31
6. TROUBLESHOOTING ...................................................................... 32
6.1 ErrorMessages ......................................................................32
6.1.1 VoltagePresent ..........................................................32
6.1.2 Overrange...................................................................33
6.1.3 NoisyMeasurement....................................................33
6.1.4 Overheating ................................................................33
MAINTENANCE ................................................................................... 34
7.1 Warning...................................................................................34
7.2 Cleaning..................................................................................34
7.3 Charging/RechargingtheBattery ...........................................35
7.4 BatteryandFuseReplacement ..............................................36
RepairandCalibration...........................................................................37
TechnicalandSalesAssistance ............................................................37
Limited Warranty ...................................................................................38
WarrantyRepairs...................................................................................38
Micro-Ohmmeter Model 6240
3
CHAPTER 1
INTRODUCTION
WARNING
These safety warnings are provided to ensure the safety of
personnelandproperoperationoftheinstrument.
• Thisinstrumentisprotectedfromaccidentalvoltagesofnot
more than 50V with respect to earth in measurement Cat-
egoryIII.
• Donotattempttoperformanytestswiththisinstrumentuntil
youhavereadtheusermanual.
• Tests are to be carried out on de-energized circuits only!
Never connect the unit to a live circuit.
• Make sure that none of the input terminals are connected
andthattheswitchissettoOFFbeforepluggingintheAC
powertorechargethebatteryoftheinstrument.
• Makesuretheinternalbatteryisfullychargedpriortotesting.
If the instrument has been left unused for several months,
rechargethebattery.
• If the case needs cleaning, do not use any alcohol or oil
based cleaners. Preferably use soapy water with a damp
clothorsponge.Donotimmersethe6240micro-ohmmeter
inwater.
• Use connection accessories of which the overvoltage cat-
egory and the service voltage are greater than or equal to
those of the measuring instrument (50V Cat. III). Use only
accessoriesthatcomplywithsafetystandards(IEC61010-2-
031).
• The test leads and measuring wires must be in good
conditionandshouldbereplacedifthereisanyevidenceof
deterioration(insulationsplit,burnt,etc.).
• Troubleshooting and metrological verication procedures
mustonlybeperformedbyqualied,approvedpersonnel,or
thefactory.
4
Micro-Ohmmeter Model 6240
1.1 International Electrical Symbols
Signifies that the instrument is protected by double or reinforced insulation.
This symbol on the instrument indicates a WARNING and that the operator must refer
to the user manual for instructions before operating the instrument. In this manual,
the symbol preceding instructions indicates that if the instructions are not followed,
bodily injury, installation/sample and/or product damage may result.
Risk of electric shock. The voltage at the parts marked with this symbol may
be dangerous.
When disposed of, this product must be sorted for the recycling of electrical
and electronic equipment in accordance with WEEE directive 2002/96/EC.
1.2 Definition of Measurement Categories
Cat. I: Formeasurements on circuits notdirectlyconnectedto theAC
supply wall outlet such as protected secondaries, signal level,
andlimitedenergycircuits.
Cat. II: For measurements performed on circuits directly connected to
the electrical distribution system. Examples are measurements
onhouseholdappliancesorportabletools.
Cat. III: For measurements performed in the building installation at
the distribution level such as on hardwired equipment in xed
installationandcircuitbreakers.
Cat. IV: For measurements performed at the primary electrical supply
(<1000V) such as on primary overcurrent protection devices,
ripplecontrolunits,ormeters.
1.3 Receiving Your Shipment
Uponreceivingyourshipment,makesurethatthecontentsareconsistent
withthepackinglist.Notifyyourdistributorofanymissingitems.Iftheequip-
mentappearstobedamaged,leaclaimimmediatelywiththecarrierand
notifyyourdistributoratonce,givingadetaileddescriptionofanydamage.
Savethedamagedpackingcontainertosubstantiateyourclaim.
NOTE: Charge the instrument fully before use.
Micro-Ohmmeter Model 6240
5
1.4 Ordering Information
Micro-ohmmeter Model 6240............................................ Cat. #2129.80
Includes set of two 10ft Kelvin clips (10A - Hippo), NiMH rechargeable battery
pack, optical USB cable, US 115V power cord, one pad of measurement results
forms, DataView®software, extra large tool bag, two spare fuses (12.5A), product
warranty and registration card and a user manual.
1.4.1 Accessories and Replacement Parts
Kelvinclips(1A),10ft color-coded leads
withbananaplugterminations.............................................Cat. #1017.83
Kelvinclips(10A-Hippo),10ftcolor-codedleads
withspadelugterminations.................................................Cat. #1017.84
Kelvinclips(10A-Hippo),20ftcolor-codedleads
withspadelugterminations................................................. Cat. #2118.70
KelvinProbes(1A-SpringLoaded),10ftwith4mmbanana
plugtermination(includessetof5forkterminals)............... Cat. #2118.73
KelvinProbes(1A-SpringLoaded),20ftwith4mmbanana
plugtermination(includessetof5forkterminals)............... Cat. #2118.74
Thermo-HygrometerModelCA846 ..................................... Cat. #2121.24
OpticalUSBCable...............................................................Cat. #2135.41
ReplacementBattery6.5V,8.5AH....................................... Cat. #2129.91
Fuse,setof5,12.5A/500V,6.3x32mm ............................. Cat. #2129.92
ExtraLargeClassicToolBag ..............................................Cat. #2133.73
MeasurementResultForms,replacementsetoftwo.......... Cat. #2129.94
Order Accessories and Replacement Parts Directly Online
Check our Storefront at www.aemc.com/store for availability
6
Micro-Ohmmeter Model 6240
CHAPTER 2
PRODUCT FEATURES
2.1 Description
The Micro-ohmmeter Model 6240 is used to perform low resistance
measurementsfrom1μΩto 400Ω.Therearesixrangeswithtestcurrents
from10mAto10A.
Thefrontendofthemicro-ohmmeteremploysafour-wireKelvincongu-
ration,whicheliminatestestleadresistanceforameasurementaccuracy
of0.25%.Abuilt-incircuitltersoutACsignals.
TheMicro-ohmmeterModel6240ispackagedinasealedeldcasewell
suitedforshopandelduse.Powerissuppliedbyalong-lifeNiMHbattery
packwithabuilt-inrecharger(110/220V).
Thelarge,easy-to-readliquidcrystaldisplayis2.25x4.00".Itdisplaysthe
valueofresistance,currentorvoltagetest,polarityandbatterycharge.
Foroperatorsafetyandinstrumentprotection,themicro-ohmmeterisfuse
protectedattheinputs.Onefuse,accessiblefromthefrontpanel,protects
againststoredenergyininductiveloads.
Enhanced internal circuitry protects against possible inductive kickback
whenthecurrentisshutoff.
Abuilt-inthermalswitchprotectsthemicro-ohmmeteragainstoverheating
onthe10Arangewhenincontinuoususe.
Micro-Ohmmeter Model 6240
7
2.2 Applications
Someofthemorepopularandmostfrequentusesofthemicro-ohmmeter
areinapplicationsfor:
Checkingmetalliccoatingresistance,especiallyinaeronautics•
Groundconnectionsandcontinuitymeasurement•
Resistancemeasurementsonmotorsandsmalltransformers•
Contactresistancemeasurementsonbreakersandswitches•
Componentmeasurement•
Electricalcableresistancemeasurement•
Mechanicalbondtests•
Wire to terminal connections•
Aircraftandrailbonds•
2.3 Key Features
Measuresfrom1µ• Ωto 400Ω
Testcurrentselectionfrom10mAto10A•
Manualtemperaturecompensation(withDataView• ®software)
Frontpanelpolarityreversefunction•
Storesupto99testresults•
Operatorsafetybyautomaticdischargeofresidualchargeonthe•
equipmentundertest
Instantaneous,continuousormultipletestoperation•
Autostoreofmultipletestresults•
Internal,rechargeablebatteriesconductupto850,10Atests•
Abuilt-inbatterypackrechargerrechargesthebatteriesby•
connectingtotheACline(110V-230V,50/60Hz)usingastandard
line cord
4-Wiremeasurementwithautomaticcompensationof•
undesirablevoltagesandleadresistance
Largemulti-functionbacklitdisplay•
Directdisplayofthemeasurementwithunits,rangeandtest•
current
Rugged,sealedcase•
8
Micro-Ohmmeter Model 6240
2.4 Control Features
°C°F
mV
mA
°
>
<
V
µmΩ
AVG
OBJ. TEST
MEMMRCLR
P
HOLD
COM
DC
AC
2nd
I
+I
_
1
7
8
6
4
235
Figure 2-1
1. Kelvininputterminals
2. AClinerechargingreceptacle
3. Outputfuse-12.5A,500V,6x32mm
4. Largemulti-linebacklitliquidcrystaldisplay(see§2.6)
5. Opticalinterfaceconnectorforconnectiontoacomputer
6. Rangeselectionswitch
7. Start/Stopbutton
8. Program/ functionbuttons(see§2.5)
Micro-Ohmmeter Model 6240
9
2.5 Button Functions
MEM Stores the measurement at an address identified by an object number
(OBJ) and a test number (TEST).
Two presses on this button are required, one to select the location (use
the▲and►buttons to change the location) and another to store the
measurement.
MR Retrieves stored data except for the OFF and SET-UP positions (this
function is independent of the selector setting of the switch). Data is
viewed using the▲and►buttons.
± I Reverses the direction of the current and displays the average.
DISPLAY Displays the current or voltage on the terminals.
AUTO>2s
Activates automatic recordings.
Used in the SET-UP and memory mode, selects a function or incre-
ments a flashing parameter.
Used in the SET-UP and memory mode, accesses the function to be
modified.
CLR Erases the memory
10
Micro-Ohmmeter Model 6240
2.6 Display Symbols
Thedisplayincorporatestwolinesofcharacterstodisplaytestresults,as
wellasalibraryofsymbolstoassisttheoperatorindeterminingconditions
ataglance.ThesymbolsthatcanappearareshowninFigure2-2.
°C°F
mV
mA
°
>
<
V
µmΩ
AVG
OBJ. TEST
MEMMRCLR
P
HOLD
COM
DC
AC
2nd
I
+I
_
Figure 2-2
Indicates the measurement is noisy; accuracy is not guaranteed
Indicates the battery charge condition; the segments represent energy
Indicates that power down is deactivated
Not used
MEM Displayed measurement about to be stored in memory
MR Memory recall
CLR
Indicates the memory is being erased
Indicates internal overheating
+ I Indicates the direction of current
- I Indicates the direction of current
Indicates that a measurement has been stopped
OBJ. First position locator for data stored in memory
TEST Second position locator for data stored in memory
°C / °F Not used
Memory utilization indicator
AVG Displays average
Not used
>Indicates an overrange
R(+I)+R(-I)
2
Micro-Ohmmeter Model 6240
11
CHAPTER 3
SPECIFICATIONS
3.1 Electrical
Specications are given for an ambient temperature of 23°C ± 3°C, rela-
tive humidity of 45 to 55%, supply voltage of 6V ± 0.2V and magnetic eld
of <40A/m.
INPUT VOLTAGE CHECK
Measurement Range 10.0 to 39.99V 40.0 to 399.99V 400 to 499V
Resolution 0.01V 0.1V 1V
Input Impedance 800kΩ
Frequency Range DC and 15.3 to 450Hz
RESISTANCE
Measurement
Range
5.0 to
3999µΩ
4.0 to
39.99mΩ
40.0 to
399.9mΩ
400 to
3999mΩ
4.0 to
39.99Ω
40.0 to
399.9Ω
Resolution 1µΩ10µΩ100µΩ1mΩ10mΩ100mΩ
Accuracy ± 0.25% ± 2ct
Measurement
current
10.2A
± 2% (1)
1.02A
± 2%
102mA
± 2%
10.2mA
± 2% (2)
Open voltage 4 to 6V
(1) With nominal value of 10.2A, the measurement current is at least 10A whatever the charge condition of the battery.
(2) The current is 10mA only up to 300Ω. If the battery is low, it can fall to as low as 8mA.
VOLTAGE MEASUREMENT INDICATION
Measurement
Range
0.01 to
3.999mV
4.0 to
39.99mV
40.0 to
399.9mV
0.40 to
3.999V
4.0 to
4.70V
Resolution 1µV 10µV 100µV 1mV 10mV
CURRENT MEASUREMENT INDICATION
Measurement
Range
5.0 to
39.99mA
40.0 to
399.9mA
0.40 to
3.999A
4.0 to
11.00A
Resolution 10µA 100µA 1mA 10mA
12
Micro-Ohmmeter Model 6240
Inuences on the Resistance Measurement
Quantities of Influence Range of use Variation of the measurement
Typical Maximum
Temperature -10 to +55°C 0.1% /10°C 0.5% /10 °C + 2cts
Relative Humidity 10 to 85% RH @ 45°C 0.1 % 0.5% + 2cts
Supply Voltage 5 to 7V 2cts 0.2% / V + 2cts
Series Mode Rejection,
50/60Hz*
U (AC) = (R measured x
I measurement) < 0.2% 2% + 1ct
Common Mode
Rejection, 50/60Hz AC 0 to 50 V AC > 80 dB > 60 dB
*Example: If the measured resistance is 1mΩand the measurement current is 10A, an alternating voltage of 1mV RMS
in series with the resistance to be measured will induce an error of not more than 2%.
Power Supply:6V,8.5AhrechargeableNiMHbatterypack
Battery Life: Rangedependent
Range Number of measurements*
10A 850
1A 3500
100mA 4500
10mA 5000
In Standby or Off battery life 4 to 6 months
*Established for measurements lasting 5s, every 25s.
3.2 Mechanical
Dimensions: 10.70x9.76x7.17"(272x248x182mm)
Weight:10lbs(4.5kgapprox)
Case Protection: ABSplasticpolycarbonate:watertighttoIP54(cover
closed),waterresistanttoIP53(coveropen).
Color:Safetyyellowcasewithgrayfaceplate
Micro-Ohmmeter Model 6240
13
3.3 Environmental
Operating Temperature:
14°to131°F(-10°to55°C),10to85%RH
Storage Temperature:
-40°to158°F(-40°to70°C);10to90%RH
Altitude:<2000m
NOTE: For long-term storage (>1 year) with the battery installed, the stor-
age range is -4 to 86°F (-20 to 30°C); 85% RH, otherwise the battery will
deteriorate. For short-term storage (1 month) the temperature can reach
up to 122°F (50°C).
3.4 Safety
ElectricalsafetyasperEN61010-1(Ed.2of2001),EN61557(Ed.97)
parts1and4.
Degreeofpollution:2
Protection:MeasurementCat.III,50Vwithrespecttoearth,500Vdiffer-
entialbetweenterminals,and300VCat.IIonthechargerinput
Electromagnetic Compatibility:
TheinstrumentsatisestheCEMandDBTdirectivesrequiredfortheCE
markingandproductstandardEN61326-1(Ed.97)+A1(Ed.98)
Emissions in residential environment
Immunityinindustrialenvironment
*All specications are subject to change without notice
14
Micro-Ohmmeter Model 6240
CHAPTER 4
OPERATION
NOTE: Charge the instrument fully before use.
4.1 Precautions Before Use
• Never usetestleadsormeasuring wires if there is any evidence of
deterioration(insulationsplit,burnt,etc).
• Never exceedthesafetyvaluesindicatedinthespecications.
• Never connecttheunittoalivecircuit.
•
Never disconnecttheconnectionwiresbeforethe icondisappears
fromthedisplay.
4.2 Instrument Configuration (SET-UP mode)
TheSET-UPmodeisusedtomodifytheinstrument’sconguration.This
canalsobeperformedbyusingtheDataView®softwarethatcamewith
theinstrument(see§5).
ToconguretheModel6240directlyfromthedisplay,turntherotaryswitch
totheSET-UPposition.Thefollowingscreenwillappear:
MEM
The display order of the parameters that can be modied is:•
- Clear all memory (see§4.9.2)
- Time
- Date
- AutomaticPowerOff
- DisplayoftheInternalParameters(e.g.serialnumber,software
version,dateoflastcalibration,lightingofallsegmentsondisplay)
Micro-Ohmmeter Model 6240
15
To display and modify parameters:
Tomovethroughparameters,pressthe• button.
To change thedisplayedparameters or view additional ones,press•
andholdthe button.
Tomodifytheparameters,usethe• button.
To accept the changes, press and hold the• button>2suntilthe
displaystopsblinking.
4.3 Resistance Measurements
WARNING: Before performing the resistance test, verify that the sample
under test is not energized.
1. Cleanallsurfacesbeforeconnectingtestleads.
2. Connectthetwoleadstothefourterminals,thenthetwoKelvinclips
totheobjecttobetested.
3. Settherangeselectorswitchtothedesiredrangeforthetest.Ifthe
anticipated resistance is not known, begin with the highest range
(400Ω) and successively lower the range selection until adequate
resolutionisachieved.
4. PresstheSTART/STOPbuttontostartthemeasurement.
NOTE: The START/STOP needs to be pressed each time the range is
changed. The range selection may be changed while the instrument is on.
HOLD
5. Press the START/STOP button again to stop the measurement or
disconnect one of the Kelvin clips. The last measurement made is
displayedalongwiththe symbol.
16
Micro-Ohmmeter Model 6240
NOTE: If the measurement was stopped by disconnecting a Kelvin clip,
simply connect it to another object to start the next measurement; It is
not necessary to press the START/STOP button.
6. Todisplaythevoltageontheterminalsoftheresistanceinsteadofthe
measurementcurrent,presstheDISPLAYkey.
Current results are displayed
before pressing DISPLAY button Voltage results are displayed
after pressing DISPLAY button
4.3.1 Measurement Readings
Whentestingresistivesamples,themeterreadingwillstabilizewithinthe
rstfewhundredmilliseconds.Oninductiveloads(e.g.smalltransform-
ers),themeasurementreadingmaytakefromseveralsecondstoafew
minutestostabilizeanddependsgreatlyonthetypeofequipmentandthe
impedanceoftheequipmentundertest.
4.3.2 Connections and Readings
The Model 6240 generates a current (I)
from the internal voltage source (V). A
voltmeter measures the voltage drop
Vx at the Kelvin probe contact points to
the resistance to be measured (Rx) and
displays the resistance measurement
(Rx)directlyusingtheformulaRx=Vx/I.
The result is not affected by the other
resistancesencountered in thecurrent
loop (Ri, Rf, Rc), as long as the total
voltagedropinducedacrossRxremains
belowthevoltagesuppliedbythesource
whichisbetween5to6V.Themaximum
admissible lead resistance level is Rf≈(V-Vx)/I.TheuseofKelvinprobes
helps,astheyeliminatetheeffectoftheleadresistance(Rf).
Ri Rf
Rf
Rf
Rf
C2
P2
P2
C1
Rc
Rx
Rc
V
I
Vx
+
Ri=Unitinternalresistance
Rf= Lead resistance
Rc= Contact resistance
Rx=Resistancetobemeasured
Micro-Ohmmeter Model 6240
17
4.3.3 Test Lead Connection
Themeasurementleadsareconnectedusingthefourbindingpostsonthe
leftsideofthefrontpanelasshownbelow.
ConnectthetworedleadstoterminalsC1andP1.Connectthetwoblack
leadstoterminalsC2andP2.
Anydropinthevoltageontheloadterminalsismeasuredbetweenthetwo
“voltage”(V)leads,P1andP2.Thecurrentleads(C1andC2)candeliver
currentfrom10mAto10A.
UI
4.4 Repetitive Measurements
1. ConnecttheKelvinclipstotherstobject.PressSTART/STOP.
2. Disconnecttheclips.Themeasurementstopsandresultisdisplayed.
3. Connect the clips to the second object. The measurement restarts
automatically.Repeatasnecessary.
4. Afterthelastmeasurement,pressSTART/STOPagain.
NOTE: This operation is valid only if all of the objects to be measured have
substantially the same value and all of the measurements are made in the
same range.
18
Micro-Ohmmeter Model 6240
4.5 Measuring Very Low Resistance
WhenmeasuringverylowresistivevaluesintheµΩrange,thepresence
ofstrayDCcurrentsmayaffecttheaccuracyofthemeasurements.These
currentscanbepresentduetoavarietyofreasonsincludingchemicalor
thermalEMFinsamplesmadeofdissimilarmetals.
Youcaneliminatetheeffectsofthisbyreversingthedirectionofcurrent
ow(seeexamplebelow)andusingtheaverageofforwardandreverse
readings.
ThepresenceofACinterferenceinthesampleundertestmaycausethe
measuredvalueonthedisplaytouctuate.Thisinterferencemaybecome
morenoticeableinthepresenceofstrongelectricelds.Theeffectsofthis
interferencemaybereducedbytwistingtheleadsaroundeachother.
1. Reversethedirectionofthecurrentbypressingthe±Ibuttonandthe
instrumentdisplaystheaverage:
R(+I)+R(-I)
RAVG = 2
2. TodisplaythevaluesR(+I)andR(-I),presstheDISPLAYbutton.
A
µ Ω
AVG
HOLD
I
_
+I
R(+I) +V
R(+I) -I
R(-I) -V
R(-I)
Press the DISPLAY button to cycle through the values
Other manuals for 6240
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