ENGLISH User Manual - Test & Measurement … GROUND RESISTANCE TESTERS ENGLISH User Manual 3640 4610 Ω Press To Measure X-Z Xv-Y Xv-Y X Y Z C1 P2 C2 Fault Hi Resistance Hi Noise GROUND

DIGITAL GROUND RESISTANCE TESTERS

E N G L I S H User Manual

36404610

ΩPress ToMeasure

X-Z

Xv-Y

Xv-Y

ZYXC1 P2 C2

Fault

Hi Resistance

Hi Noise

GROUND RESISTANCE TESTERMODEL 3640

AUTORANGINGREFER TO USER MANUALFOR FAULT WARNING LIGHTEXPLANATIONS

!

®

I N S T R U M E N T S

ΩPress ToMeasure

X-Z

Xv-Y

Xv-Y

ZYX XvC1 P1 P2 C2

Fault

Hi Resistance

Hi Noise



!

®


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 #: ______________________________

Model #: 3640 / 4610

Please fill in the appropriate date as indicated:

Date Received: _________________________________

Date Calibration Due: _______________________

Chauvin Arnoux®, Inc.d.b.a AEMC® Instrumentswww.aemc.com

Digital Ground Resistance Tester Model 3640 and 4610 1

Table of Contents

1. INTRODUCTION ................................................................................. 31.1 International Electrical Symbols ................................................31.2 DefinitionofMeasurementCategories .....................................41.3 ReceivingYourShipment ..........................................................41.4 OrderingInformation .................................................................4

1.4.1 Kits,AccessoriesandReplacementParts ....................5

2. PRODUCT FEATURES ......................................................................... 62.1 3640ControlandConnectorIdentification ...............................62.2 4610ControlandConnectorIdentification ...............................72.3 FaultIndicatorLEDs .................................................................8

2.3.1 X-ZFault .......................................................................82.3.2 X-YHighResist.(3640)-Xv-YHighResist. ....................... 82.3.3 X-YHighNoise(3640)-Xv-YHighNoise(4610) ...........8

2.4 Over-rangeIndication ...............................................................92.5 FaultLEDIndication–TipsandSolutions ................................9

3. SPECIFICATIONS ............................................................................. 103.1 Electrical .................................................................................103.2 Mechanical ..............................................................................113.3 Environmental .........................................................................113.4 SafetySpecifications ..............................................................113.5 Auto-ranging ...........................................................................12

4. OPERATION ..................................................................................... 134.1 GroundingElectrodeResistance ............................................13

4.1.1 EffectofGroundElectrodeSize/DepthonResist. ......154.1.2 EffectsofSoilResistivityonElectrodeResistance .....164.1.3 FactorsAffectingSoilResistivity .................................164.1.4 EffectofGroundRodDepthonResistance ................19

4.2 GroundResistanceValues .....................................................204.3 GroundResistanceTestingPrinciple .....................................22

4.3.1 PositionofAuxiliaryElectrodesinMeasurements ......234.4 MeasuringResistanceofGroundElectrodes .........................24

2 Digital Ground Resistance Tester Model 3640 and 4610

4.4.1 AuxiliaryElectrodeSpacing ........................................274.5 GroundResistanceMeasurementProcedure ........................284.6 MultipleElectrodeSystem ......................................................294.7 2-PointMeasurement(SimplifiedMeasurement) ............. 314.8 ContinuityMeasurement .........................................................324.9 SoilResistivityMeasurements(Model4610Only) .................334.10SoilResistivityMeasurementProcedure(4-Point) .................344.11HowtoUse25ΩCalibrationChecker .....................................36

5. MAINTENANCE ................................................................................ 375.1 Warning...................................................................................375.2 Cleaning ..................................................................................375.3 ReplacingtheBattery .............................................................375.4 ReplacingtheSafetyFuse ......................................................38RepairandCalibration ....................................................................39TechnicalandSalesAssistance ......................................................39Limited Warranty .............................................................................40WarrantyRepairs ............................................................................40


CHAPTER 1

INTRODUCTION

WARNING “It should be impressed on all personnel that a lethal potential can exist between the station ground and a remote ground if a system fault involving the station ground occurs while tests are being made. Since one of the objects of tests on a station ground is the establishment of the location of an effectively remote point for both current and potential electrodes, the leads to the electrodes must be treated as though a possible potential could exist between these test leads and any point on the station ground grid.”

- excerpted from IEEE Std. 81-1962

Thesesafetywarningsareprovidedtoensurethesafetyofpersonnelandproperoperationoftheinstrument.• The instrument must not be operated beyond its specified operatingrange.

• Safetyistheresponsibilityoftheoperator.• Allmetalobjectsorwiresconnectedtotheelectricalsystemshouldbeassumedtobelethaluntiltested.Groundingsystemsarenoexception.

• Use extreme caution when using the instrument around energizedelectricalequipment.

• Neverattempttousetheinstrumenttotwistorprythegroundelectrodeorgroundwireawayfromtheequipmentbeinggrounded.

• The use of rubber gloves is an excellent safety practice even if theequipmentisproperlyoperatedandcorrectlygrounded.

• Always inspect the instrument and leads prior to use. Replace anydefectivepartsimmediately.

1.1 International Electrical SymbolsThis symbol 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 product damage may result.Risk of electric shock. The voltage at the parts marked with this symbol may be dangerous.

In conformity with WEEE 2002/96/EC


1.2 Definition of Measurement CategoriesCAT II: Formeasurements performed on circuits directly connected to

theelectricaldistributionsystem.Examplesaremeasurementsonhouseholdappliancesorportabletools.

CAT III: For measurements performed in the building installation atthe distribution level such as on hardwired equipment in fixedinstallationandcircuitbreakers.

CAT IV: For measurements performed at the primary electrical supply(<1000V) such as on primary overcurrent protection devices,ripplecontrolunits,ormeters.

1.3 Receiving Your ShipmentUponreceivingyourshipment,makesurethatthecontentsareconsistentwith the packing list. Notify your distributor of anymissing items. If theequipmentappearstobedamaged,fileaclaimimmediatelywiththecar-rierandnotifyyourdistributoratonce,givingadetaileddescriptionofanydamage.Savethedamagedpackingcontainertosubstantiateyourclaim.

1.4 Ordering InformationGround Resistance Tester Model 3640 ............................ Cat. #2114.92Includes soft carrying case, batteries and a user manual.

Ground Resistance Tester Model 3640 Kit (150 ft) .........Cat. #2135.13Includes ground tester, two 150 ft color-coded leads on spools (red/blue), one 30 ft lead (green), two T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag and user manual.

Ground Resistance Tester Model 3640 Kit (300 ft) .........Cat. #2135.14Includes ground tester, two 300 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag and user manual.

Ground Resistance Tester Model 3640 Kit (500 ft) .........Cat. #2135.15Includes ground tester, two 500 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), one 30 ft lead (green), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag, and user manual.

Ground Resistance Tester Model 4610 ............................ Cat. #2114.94Includes soft carrying case, batteries and a user manual.

Ground Resistance Tester Model 4610 Kit (150 ft) .........Cat. #2135.16Includes ground tester, two 150 ft color-coded leads on spools (red/blue), one 30 ft lead (green), two T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag and user manual.


Ground Resistance Tester Model 4610 Kit (300 ft) .........Cat. #2135.17Includes ground tester, two 300 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag and user manual.

Ground Resistance Tester Model 4610 Kit (500 ft) .........Cat. #2135.18Includes ground tester, two 500 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), one 30 ft lead (green), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, batteries, carrying bag and user manual.

1.4.1 Kits, Accessories and Replacement Parts

Test Kit for 3-Point Testing ...............................................Cat. #2135.35Includes two 150 ft color-coded leads on spools (red/blue), one 30 ft lead (green), two T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, carrying bag.

Test Kit for 4-Point Testing ...............................................Cat. #2135.36Includes two 300 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, carrying bag.

Test Kit for 4-Point Testing ...............................................Cat. #2135.37Includes two 500 ft color-coded leads on spools (red/blue), two 100 ft color-coded leads (hand-tied, green/black), one 30 ft lead (green), four T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, carrying bag.

Test Kit for 3-Point Testing (Supplementalfor4-PointTesting) ...Cat. #2135.38Includes two 100 ft color-coded leads (hand-tied, green/black), one 30 ft lead (green), two T-shaped auxiliary ground electrodes, set of 5 spaded lugs, one 100 ft AEMC® tape measure, carrying bag.

Set of 2, T-Shaped Auxiliary Ground Electrodes ............Cat. #2135.39Ground Tester Video/Workbook Set ................................Cat. #2130.6425Ω Calibration Checker ...................................................Cat. #2130.59Tape Measure – AEMC 100 ft ............................................Cat. #2130.60Fuse – Set of 5, 0.1A, >250V, 0.25 x 1.25" ........................Cat. #2970.12

Order Accessories and Replacement Parts Directly OnlineCheck our Storefront at www.aemc.com/store for availability


CHAPTER 2

PRODUCT FEATURES

2.1 3640 Control and Connector Identification

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYXC1 P2 C2

Fault

Hi Resistance

Hi Noise

GROUND RESISTANCE TESTER

MODEL 3640

AUTORANGINGREFER TO USER MANUAL

FOR FAULT WARNING LIGHT

EXPLANATIONS

!

2 3 4 5

6

78910

1

Figure 1

1. Press-to-Measurebutton

2. InputterminalX(C1)

3. InputterminalY(P2)

4. Groundresistanceshortinglink

5. InputterminalZ(C2)

6.Display

7. Lowbatteryindicator

8.Xv-Yhighnoiseindicator

9.Xv-Yhighresistanceindicator

10.X-Zfaultindicator


2.2 4610 Control and Connector Identification

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

2 3 4 5 6

7

891011

1

Figure 2

1. Press-to-Measurebutton

2. InputterminalX(C1)

3. InputterminalXv(P1)

4. InputterminalY(P2)

5. Groundresistanceshortinglink

6. InputterminalZ(C2)

7.Display

8. Lowbatteryindicator

9.Xv-Yhighnoiseindicator

10.Xv-Yhighresistanceindicator

11. X-Zfaultindicator


2.3 Fault Indicator LEDsThe three indicators describedbelowconfirm the correctmeasurementbeingtakenifnoneofthemarelit.

2.3.1 X-Z Fault

ThisLEDsignalsthatvoltagebetweenterminalsXandZexceeds30Vpeak.

Therearefourpossiblecauses:• theresistanceofthecurrentcircuitbetweenXandZistoohigh• interferencevoltageinthecurrentcircuitistoohigh• thefuseisblown• thecircuitisopen(leadnotconnected)

2.3.2 X-Y High Resistance (3640) - Xv-Y High Resistance (4610)

ThisLEDsignalsthattheresistanceinthevoltagecircuit(betweenXvandYorXandY)istoohigh(approx50kΩ)orthatthecircuitmaybeopen.

• Flashingwill continue throughout themeasurement,even if theresistancedropsbelowthethreshold(e.g.afterreconnectingorloweringauxiliaryrodresistance).

• In thiscase,youmustreleasethepush-buttonandpressagainafterthefaulthasbeencorrected.

• Occasionally, a stray voltageabove6VDCmayalso set off thislight.

• Checktheleadsforapossiblesolution.

2.3.3 X-Y High Noise (3640) - Xv-Y High Noise (4610)

ThisLEDsignalsthepresenceofexcessivenoise(approx13Vpeak)inthevoltagecircuit(betweenXvandYorXandY).

• Oneremedyistouseshieldedleadsfromtheinstrumenttotheauxiliaryelectrodes.

• Connectalltheshieldstotherodundertest.


2.4 Over-range IndicationOver-rangeisindicatedwhenthedisplayreads1,orwhenthedisplayisblinkingandtheindicatorislit.

2.5 Fault LED Indication – Tips and SolutionsTheLEDindicatorsshowexcessiveelectroderesistanceandexcessivetransientnoiseand/orstraycurrent.Intheeventofanincorrectmeasurementindication:

• ImprovethequalityoftheconnectiontoearthofauxiliarygroundelectrodesYandZ.Zisthemostlikelysourceofproblemscausedbyexcessiveelectroderesistance.

• Checkconnectionsforcontinuitybetweenleadsandelectrodes.• Be sure that electrodes are properly inserted; they should be

buriedasmuchaspossible.• Ifhighelectroderesistancestillexistsafterproperlyinsertingaux-

iliaryelectrodesintotheearth,trypouringwateronandaroundtheauxiliaryelectrodes.Thiswillimprovetheirelectricalconnec-tiontoearth.

• Ifstraycurrentsaresuspected,onesolutiontoreducetheirinflu-enceistomovebothYandZelectrodesinanarcrelativetotheXelectrode(try,e.g.,a90°shift),andtestagain.

• Displayof0.00:XvandYareshort-circuited.• Displayof<0:XandZorXvandYrodsarereversed.

NOTE: Accuracy may be affected by auxiliary ground rod (Ry, Rz) resistance levels and by stray signal levels (earth currents).


CHAPTER 3

SPECIFICATIONS

3.1 ElectricalMeasurement Ranges:Auto-ranging0to2000Ω

Range 20Ω 200Ω 2000ΩMeasurement 0 to 19.99Ω 20 to 199.9Ω 200 to 1999ΩResolution 10mΩ 100mΩ 1ΩTest Current 10mA 1mA 0.1mAAccuracy ± 2% of Reading ± 1ct ± 5% of Reading ± 3ctsOpen Voltage <42V peak

Operating Frequency:128Hzsquarewave

Max. Auxiliary Rod Resistance:Range 20Ω 200Ω 2000ΩCurrent Circuit 3kΩ 30kΩ 50kΩVoltage Circuit 50kΩ

Response Time: Approximately6secondsforastabilizedmeasurement

Interference: Models3640&4610aredesignedtorejecthighlevelsofinterferencevoltage(DC,50/60Hz,harmonics)

• DCvoltageinserieswithX:20V• ACvoltageinserieswithY:13Vpeak• ACvoltageinserieswithZ:32Vpeak

Accuracies and specifications are given for an ambient temperature of 23°C ± 3°, RH of 45 to 55%, battery power at 8V, auxiliary resistance at the measurement terminals <200Ω, no stray voltage and a magnetic field from 0 to 40A/m.

Power Source: Eight1.5V“AA”batteries;Alkalinerecommended.

Battery Life: 180015-secondmeasurements

Low Battery Indicator: Ifthe“LoBat”indicatorlightsup,thebatteriesarelosingpower.Theavailableoperatingtimeremainingis10015-secondmeasurements(approx).

Fuse Protection: Highbreakingcapacity-0.1A,>250V,0.25x1.25"


3.2 MechanicalConnection:Color-codedterminalsacceptspadelugswithminimumgapof6mmorstandard4mmbananajacks

Display:7segmentLCD,.71"(18mm)high(3-1/2digit);2000ctsLCDalsoindicatesoverrange,testleadshortsandleadreversals.

Dimensions:8.7x5.4x5.9"(220x136x150mm)

Weight: 2.9lbs(1.3kg)

Case: Heavy-duty,ABS

Colors: Case-safetyyellow;Frontpanel-gray

Mechanical Shock: IEC 68-2-27

Vibration: IEC 68-2-6

Drop Test: IEC 68-2-32

Case Material: UL94

Environmental: O-ringsealedagainstdustandwatertoIP50

3.3 EnvironmentalOperating Temperature: 14°to131°F(-10°to55°C);0to90%RH

Storage Temperature:-40°to158°F(-40°to70°C); 0to90%RHwithbatteriesremoved

3.4 Safety Specifications

Electrical: EN61010-1,CATlII,PollutionDegree2,42V

Electromagnetic Compatibility: Emission:EN61326-1 Immunity:EN61326-1

*Specifications are subject to change without notice.


3.5 Auto-rangingTheselectionofthemeasurementcurrentisdependingontheresistancetomeasure.

WhentheinstrumentisturnedON,themeasurementstartsonthesmallestcurrentrange(100µA).Ifthemeasurementisbetween185and1950cts,therangestaysthesame(100µA).Ifthemeasurementisunder185cts,thecurrentismultipliedby10(within10mAmax).Ifitisabove1950cts,thecurrentisdividedby10(withoutgoingunder100µA).

Thisisdonetoavoidswitchingbackandforthbetweenrangeswhenyouaremeasuring190Ω.Itispossibletodisplay190.0or190Ωdependingontheautomaticrangeselection.


CHAPTER 4

OPERATION

4.1 Grounding Electrode ResistanceFigure3illustratesagroundingrod.Theresistanceoftheelectrodehasthefollowingcomponents:

• theresistanceofthemetalandthatoftheconnectiontoit• thecontactresistanceofthesurroundingearthtotheelectrode• theresistanceinthesurroundingearth

Morespecifically:A) Groundingelectrodesareusuallymadeofaveryconductivemetal

(copper)withadequatecrosssectionssothatoverallresistanceisnegligible.

B) TheNationalInstituteofStandardandTechnology(N.I.S.T.)hasdemonstratedthattheresistancebetweentheelectrodeandthesurrounding earth is negligible if the electrode is free of paint,greaseorothercoating,andiftheearthisfirmlypacked.

Ground Rodand Clamp

Contact ResistanceBetween Rod and Soil

ConcentricShells of Earth

Figure 3


C) The only component remaining is the resistance of the surround-ing earth. The electrode can be thought of as being surrounded by concentric shells of earth or soil, all of the same thickness. The closer the shell to the electrode, the smaller its surface; hence, the greater its resistance. The farther away the shells are from the electrode, the greater the surface of the shell; hence, the lower the resistance. Eventually, adding shells at a distance from the grounding electrode will no longer noticeably affect the overall earth resistance surrounding the electrode. The distance at which this effect occurs is referred to as the effective resistance area and is directly dependent on the depth of the grounding electrode.

In theory, the ground resistance may be derived from the general formula:

R = ρ Resistance = Resistivity xLA

LengthArea

This formula clearly illustrates why the shells of concentric earth decrease in resistance the farther they are from the ground rod:

R = Resistivity of Soil x Thickness of ShellArea

In the case of ground resistance, uniform earth (or soil) resistivity through-out the volume is assumed, although this is seldom the case in nature. The equations for systems of electrodes are very complex and often expressed only as approximations. The most commonly used formula for single ground electrode systems, developed by Professor H. R. Dwight of the Massachusetts Institute of Technology, follows:

4Lr

R =ρ

2πLIn -1

R = resistance in ohms of the ground rod to the earth (or soil)

L = grounding electrode length

r = grounding electrode radius

ρ = average resistivity in ohms-cm


4.1.1 Effect of Ground Electrode Size and Depth on Resistance

Size: Increasing thediameter of the roddoesnotmaterially reduce itsresistance.Doublingthediameterreducesresistancebylessthan10%.

0255075

100

1/2 5/8 3/4 1 1 1/4 1 1/2 1 3/4

Rod Diameter (inches)

Res

ista

nce

in %

Figure 4

Depth: As a ground rod is driven deeper into the earth, its resistanceissubstantiallyreduced.Ingeneral,doublingtherodlengthreducestheresistancebyanadditional40%.

5 15 25 35 40 50 60 701

2

34568

10

20

3040

6080

100

200

Driven Depth in FeetGround Resistance Versus Ground Rod Depth

Res

ista

nce

in O

hms

1/2" dia.1" dia.

Figure 5


NEC®2014250.52(A)(5)requiresaminimumof8ft(2.4m)oftheelec-trodetobe incontactwith thesoil.Themostcommonofelectrode isa10ft(3m)cylindricalrodwhichmeetstheNEC®code,whichrequiresaminimumdiameterof5/8"(1.59cm).

4.1.2 Effects of Soil Resistivity on Ground Electrode ResistanceDwight’s formula,citedpreviously,showsthat theresistance toearthofgroundingelectrodesdependsnotonlyonthedepthandsurfaceareaofgroundingelectrodesbutonsoilresistivityaswell.Soilresistivity isthekeyfactorthatdetermineswhattheresistanceofagroundingelectrodewillbe,andtowhatdepthitmustbedriventoobtainlowgroundresistance.Theresistivityofthesoilvarieswidelythroughouttheworldandchangesseasonally.Soilresistivityisdeterminedlargelybyitscontentofelectro-lytes,consistingofmoisture,mineralsanddissolvedsalts.Adrysoilhashighresistivityifitcontainsnosolublesalts.

SoilAshes, cinders, brine, waste

Clay, shale, gumbo, loamSame, with varying proportionsof sand and gravelGravel, sand, stones withlittle clay or loam

590

340

1,020

59,000

2,370

4,060

15,800

94,000

7,000

16,300

135,000

458,000

Resistivity, Ω-cm

Minimum Average Maximum

Table 1

4.1.3 Factors Affecting Soil Resistivity

Twosamplesofsoil,whenthoroughlydried,maybecomeinfactverygoodinsulators, having a resistivity in excess of 109 ohm-centimeters. Theresistivityofthesoilsampleisseentochangequiterapidlyuntilapproxi-matelytwentypercentorgreatermoisturecontentisreached.


02.55

10152030

> 109250,000165,00053,00019,00012,0006,400

> 109150,00043,00018,50010,5006,3004,200

Resistivity, Ω-cmMoisture content,% by weight Top Soil Sandy Loam

Table 2

Theresistivityofthesoilisalsoinfluencedbytemperature.Table3showsthevariationoftheresistivityofsandyloam,containing15.2%moisture,withtemperaturechangesfrom20°to-15°C.Inthistemperaturerangetheresistivityisseentovaryfrom7,200to330,000ohm-centimeters.

201000-5-15

6850

32 (water)32 (ice)

2314

7,2009,90013,80030,00079,000330,000

ResistivityΩ-cm

Temperature

°C °F

Table 3

Becausesoil resistivitydirectly relates tomoisturecontentand temper-ature, it is reasonable to assume that the resistance of any groundingsystemwillvarythroughoutthedifferentseasonsoftheyear.Suchvaria-tionsareshowninFigure6below.Since both temperature and moisture content become more stable atgreaterdistancesbelowthesurfaceoftheearth,itfollowsthatagroundingsystem(tobemosteffectiveatalltimes)shouldbeconstructedwiththegroundroddrivendownaconsiderabledistancebelowthesurfaceoftheearth.Bestresultsareobtainedifthegroundrodreachesthewatertable.


0

20

40

60

80

Jan.

Mar

.

May

July

Sep

t.

Nov

.

Jan.

Mar

.

May

July

Curve 1

Curve 2

Figure 6

Seasonal variation of earth resistance with an electrode of 3/4" pipe in rather stony clay soil. Depth of electrode in earth is 3 ft for Curve 1, and 10 ft for Curve 2.

Insomelocations,theresistivityoftheearthissohighthatlow-resistancegroundingcanbeobtainedonlyatconsiderableexpenseandwithanelab-orategroundingsystem.Insuchsituations, itmaybeeconomical touseagroundrodsystemoflimitedsizeandtoreducethegroundresistivitybyperiodicallyincreasingthesolublechemicalcontentofthesoil.Table4showsthesubstantialreductioninresistivityofsandyloambroughtaboutbyanincreaseinchemicalsaltcontent.

00.11.05

1020

10,7001,800460190130100

The Effect of Salt* Content on the Resistivity of Soil(sandy loam, moisture content, 15% by weight, temperature 17°C)

Added Salt% by weight of moisture

Resistivity(Ohm-centimeters)

Table 4

Chemicallytreatedsoilisalsosubjecttoconsiderablevariationofresistiv-itywithchangesintemperature,asshowninTable5.Ifsalttreatmentisemployed,itis,ofcourse,necessarytousegroundrodswhichwillresistchemicalcorrosion.


20100-5

-13

110142190312

1440

The Effect of Temperature on the Resistivity of Soil Contining Salt*(sandy loam, 20% moisture; salt 5% of weight of moisture)

Temperature °C Resistivity (Ohm-centimeters)

Table 5

*Suchascoppersulfate,sodiumcarbonateandothers.SaltsmustbeEPAorlocalordinanceapprovedpriortouse.

4.1.4 Effect of Ground Rod Depth on ResistanceToassisttheengineerindeterminingtheapproximategroundroddepthrequired to obtain a desired resistance, a device called theGroundingNomographmaybeused.TheNomograph,shownonthefollowingpage,indicatesthattoobtainagroundingresistanceof20ohmsinasoilwitharesistivityof10,000ohm-centimeters,a5/8"ODrodmustbedriven20ft.Note that the values indicated on theNomograph are based on theassumption that the soil is homogeneous and, therefore, has uniformresistivity(Figure7).TheNomographvalueisanapproximation.


Grounding Nomograph

Ground Rod

Resistance-Ohms

Soil Resistivity

(Ohm-centimeters)

Rod Depth

Feet

Rod Diameter

Inches

R

P

D

DIA

20

3040

90

5060

7080

100

15

10

1

5

2

4

3

5/8

1/4

1/2

3/4

1

1.5

87

65

43

2

10000

15000

10000050000

4000030000

20000

3000

500

1000

2000

40005000

20

30

10090

8070

6050

40

15

1

2

3

4

5

67

89

10

K

Figure 7

1. SelectrequiredresistanceonRscale.

2. SelectapparentresistivityonPscale.

3. Lay straightedge on R and P scale, and allow to intersect with Kscale.

4. MarkKscalepoint.

5. LaystraightedgeonKscalepointandDIAscale,andallowtointersectwithDscale.

6. PointonDscalewillberoddepthrequiredforresistanceonRscale.

4.2 Ground Resistance ValuesNEC®2008article250.56regardingtheresistanceofrod,pipeandplateelectrodesstatesthatiftherod,pipe,orplatedoesnothavearesistanceof25Ωorlesstogroundshallbeaugmentedbyoneadditionalelectrodeofanyofthetypesspecifiedby250.52(A)(4)through(A)(8).Wheremultiplerod,pipeorplateelectrodesareinstalledtomeettherequirementsofthesection,theyshallnotbelessthan6feetapart.


FPN:Theparallelingefficiencyofrodslongerthan8feetisimprovedbyspacinggreaterthan6feetapart.

TheNationalElectricalCode® (NEC®)statesthattheresistancetogroundshallnotexceed25Ω.This isanupper limitandguideline,sincemuchlowerresistanceisrequiredinmanyinstances.

“How low in resistance should a ground be?”Anarbitraryanswertothisinohmsisdifficult.Thelowerthegroundresis-tance,thesafer,andforpositiveprotectionofpersonnelandequipment,itisworththeefforttoaimforlessthanoneohm.Itisgenerallyimpracticaltoreachsuchalowresistancealongadistributionsystemoratransmis-sionlineorinsmallsubstations.Insomeregions,resistancesof5Ω or less maybeobtainedwithoutmuchtrouble.Inothers,itmaybedifficulttobringresistanceofdrivengroundsbelow100Ω.

Acceptedindustrystandardsstipulatethattransmissionsubstationsshouldbedesignednottoexceedoneohmresistance.Indistributionsubstations,themaximumrecommendedresistanceis5Ω.Inmostcases,theburiedgridsystemofanysubstationwillprovidethedesiredresistance.

Inlightindustrialorintelecommunicationscentraloffices,5Ωisoftentheacceptedvalue.Forlightningprotection,thearrestersshouldbecoupledwithamaximumgroundresistanceof1Ω.

Theseparameterscanusuallybemetwiththeproperapplicationofbasicgroundingtheory.Therewillalwaysexistcircumstanceswhichwillmakeit difficult to obtain the ground resistance required by theNEC®.Whenthesesituationsdevelop,severalmethodsof loweringthegroundresis-tancecanbeemployed.Theseincludeparallelrodsystems,deepdrivenrod systemsutilizing sectional rods and chemical treatment of the soil.Additionalmethods,discussedinotherpublisheddata,areburiedplates,buried conductors (counterpoise), electrically connected building steel,andelectricallyconnectedconcretereinforcedsteel.

Electricallyconnectingtoexistingwaterandgasdistributionsystemswasoftenconsideredtoyieldlowgroundresistance;however,recentdesignchangesutilizingnon-metallicpipesandinsulatingjointshavemadethismethodofobtaininga lowresistancegroundquestionableand inmanyinstancesunreliable.

Groundrods,ofcourse,willberequiredinhighvoltagetransmissionlines,wheremaximumresistanceof15ohmsisrecommended;andindistribu-tionlines,wheremaximumresistanceof25ohmsispreferred.Allelectri-calsystemsconstructedinaccordancewiththeNationalElectricalCode®, shouldnotexceed25ohms.


The measurement of ground resistances may only be accomplishedwith specially designed test equipment. Most instruments use the Fallof Potential principle of alternating current (AC) circulating between anauxiliaryelectrodeandthegroundelectrodeunder test; thereadingwillbegiveninohmsandrepresentstheresistanceofthegroundelectrodetothesurroundingearth.AEMC®Instrumentshasalsorecentlyintroducedaclamp-ongroundresistancetester.

Note: The National Electrical Code® and NEC® are registered trademarks of the National Fire Protection Association.

4.3 Ground Resistance Testing Principle (Fall-of-Potential — 3-Point Measurement)

Three-point measurement is used to measure resistance to ground ofgroundrodsandgrids.ThepotentialdifferencebetweenrodsXandYismeasuredbyavoltmeter,andthecurrentflowbetweenrodsXandZismeasuredbyanammeter.

ByOhm’sLawE=RIorR=E/I,wemayobtain thegroundelectroderesistance R.IfE=20VandI=1A,then:

R===20ohmsEI

201

Itisnotnecessarytocarryoutallthemeasurementswhenusingagroundtester.Thegroundtesterwillmeasuredirectlybygeneratingitsowncur-rentanddisplayingtheresistanceofthegroundelectrode.


ZYX

VOLTMETER (E)

AUXILIARYPOTENTIAL

ELECTRODE

GROUNDELECTRODEUNDER TEST

AUXILIARYCURRENT

ELECTRODE

AMMETER (I)

CURRENTSUPPLY

R

EARTH

Figure 8

NOTE: Terminals X and Xv are shorted together in three-point measurement

4.3.1 Position of the Auxiliary Electrodes in MeasurementsThegoalinpreciselymeasuringtheresistancetogroundistoplacetheauxiliarycurrentelectrodeZfarenoughfromthegroundelectrodeundertestsothattheauxiliarypotentialelectrodeYwillbeoutsideoftheeffec-tiveresistanceareasofboththegroundelectrodeandtheauxiliarycurrentelectrode.ThebestwaytofindoutiftheauxiliarypotentialrodYisoutsidetheeffectiveresistanceareasistomoveitbetweenXandZandtotakeareadingateachlocation.IftheauxiliarypotentialrodYisinaneffectiveresistancearea(orinbothiftheyoverlap),bydisplacingit,thereadingstakenwillvarynoticeablyinvalue.Undertheseconditions,noexactvaluefortheresistancetogroundmaybedetermined.


X-Y Distance

Res

ista

nce

Reading Variation

Effective ResistanceAreas (Overlapping)

X Y' Y Y'' Z

Figure 9

On the other hand, if the auxiliary potential rodY is located outside oftheeffectiveresistanceareas,asYismovedbackandforththereadingvariationisminimal.Thereadingstakenshouldberelativelyclosetoeachother,andarethebestvaluesfortheresistancetogroundofthegroundX.Thereadingsshouldbeplottedtoensurethattheylieina“plateau”regionasshowninFigure10.

X-Y Distance

Res

ista

nce

Reading Variation

Effective ResistanceAreas (No Overlap)

X Y Y Y'' Z

Figure 10

4.4 Measuring Resistance of Ground Electrodes

(62% Method)

The 62%method has been adopted after graphical consideration andafteractualtest.Itisthemostaccuratemethodbutislimitedbythefactthatthegroundtestedisasingleunit.Thismethodappliesonlywhenallthreeelectrodesareinastraightlineandthegroundisasingleelectrode,pipe,orplate,etc.,asinFigures11and12.


Model 3640

Alligator Clips

Y ZX52% 62% 72%0% 100% of distance

between X and Z

Ground Rod Y Electrode Z Electrode

Ground Rod

Y Electrode Z Electrode

GroundStrip

-10% 3rdMeasurement

+10% 2ndMeasurement

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

®


46.9

Figure 11

Model 4610

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

Fault

Hi Resistance

Hi Noise



EXPLANATIONS

!

®


Alligator ClipsGround Rod


GroundStrip


MODEL 4610

ZYX Xv

C1 P1 P2 C2

Figure 12

ConsiderFigure13,whichshowstheeffectiveresistanceareas(concentricshells)ofthegroundelectrodeXandoftheauxiliarycurrentelectrodeZ.Theresistanceareasoverlap.IfreadingsweretakenbymovingtheauxiliarypotentialelectrodeYtowardseitherXorZ,thereadingdifferentialswouldbegreat andone couldnot obtaina readingwithin a reasonablebandoftolerance.Thesensitiveareasoverlapandactconstantlyto increaseresistanceasYismovedawayfromX.


Distance from Y to Ground Electrode

Res

ista

nce

Overlapping EffectiveResistance Areas

X Y Z

GroundElectrode

Under Test

AuxiliaryPotentialElectrode

AuxiliaryCurrent

Electrode

Figure 13

NowconsiderFigure 14,where theXandZelectrodesare sufficientlyspacedsothattheareasofeffectiveresistancedonotoverlap.Ifweplottheresistance,measuredwefindthatthemeasurementsleveloffwhenYisplacedat62%ofthedistancefromXtoZ,andthatthereadingsoneithersideoftheinitialYsettingaremostlikelytobewithintheestablishedtoleranceband.Thistolerancebandisdefinedbytheuserandexpressedasapercentoftheinitialreading:±2%,±5%,±10%,etc.

Res

ista

nce

Distance from Y to Ground Electrode

Effective ResistanceAreas Do

Not Overlap

X Y Z

GroundElectrode

Under Test

AuxiliaryPotentialElectrode

AuxiliaryCurrent

Electrode

D62% of D 38% of D

Resistance ofAuxiliary CurrentElectrode

Resistance of Earth Electrode

Figure 14


4.4.1 Auxiliary Electrode SpacingNodefinitedistancebetweenXandZcanbegiven,sincethisdistanceisrelativetothediameteroftheelectrodetested,itslength,thehomogeneityof the soil tested, andparticularly, the effective resistanceareas.How-ever,anapproximatedistancemaybedeterminedfromthefollowingchartwhichisgivenforahomogeneoussoilandanelectrodeof1"indiameter.(Foradiameterof1/2",reducethedistanceby10%;foradiameterof2"increasethedistanceby10%.)

Depth Driven Distance to Y Distance to Z 6 ft 45 ft 72 ft 8 ft 50 ft 80 ft 10 ft 55 ft 88 ft 12 ft 60 ft 96 ft 18 ft 71 ft 115 ft 20 ft 74 ft 120 ft 30 ft 86 ft 140 ft

Approximate Distance to Auxiliary ElectrodesUsing the 62% Method

Table 6


4.5 Ground Resistance Measurement Procedure

(3-Point)

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYXC1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 3640



EXPLANATIONS

!

®


Alligator ClipsGround Rod


GroundStrip

Figure 15

WARNING: Use extreme caution when disconnecting the ground connection from the rest of the circuit. Current may be flowing and a dangerous potential could exist between the disconnected wires.

• XandXv(C1,P1)areshorted• DisconnectshortinglinkbetweenYandZ(C2,P2)• ConnectXtothegroundrodtobetested• ConnectY(P2)tothecentralelectrode• ConnectZ(C2)totheouterelectrode• Depressthe“Measure”buttontomeasuregroundresistance


4.6 Multiple Electrode SystemAsingledrivengroundelectrodeisaneconomicalandsimplemeansofmakingagoodgroundsystem,butsometimesasinglerodwillnotprovidesufficientlowresistance,andseveralgroundelectrodeswillbedrivenandconnectedinparallelbyacable.Veryoftenwhentwo,threeorfourgroundelectrodesareused,theyaredriveninastraightline.Whenfourormoreareused,ahollowsquarecon-figurationisusedandthegroundelectrodesarestillconnectedinparallelandequallyspaced(Figure16).Inmultipleelectrodesystems,the62%methodelectrodespacingmaynolongerbeapplieddirectly.Thedistanceoftheauxiliaryelectrodesisnowbasedonthemaximumgriddistance(e.g.,inasquare,thediagonal;inaline,thetotallength).Asquarehavingasideof20 ftwillhaveadiagonalofapproximately28ft.

DIAGONAL

DIAG

ON

AL

a

a a

a

Figure 16


6 ft8 ft10 ft12 ft14 ft16 ft18 ft20 ft30 ft40 ft50 ft60 ft80 ft100 ft120 ft140 ft160 ft180 ft200 ft



Multiple Electrode SystemMax Grid Distance Distance to Y Distance to Z

Table 7


4.7 2-Point Measurement (Simplified Measurement)

Thisisanalternativemethodtothree-pointmeasurementwhen an excel-lent ground is already available.Incongestedareaswherefindingroomtodrivethetwoauxiliarygroundelectrodesmaybeaproblem, the two-pointmeasurementmethodmaybeapplied.Thereadingobtainedwillbethatofthetwogroundsinseries.Therefore,thewaterpipeorothergroundmustbeverylowinresistancesothatitwillbenegligibleinthefinalmeasurement.Theleadresistanceswillalsobemeasuredandshouldbededucted from thefinalmeasure-ment.Thismethodisnotasaccurateasthree-pointmethods(62%method),asitisparticularlyaffectedbythedistancebetweenthetestedelectrodeandthedeadgroundorwaterpipe.Thismethodshouldnotbeusedasastan-dardprocedure,butratherasabackupintightareas.SeeFigure17.

Procedure:

• ShortXandXv(C1,P1)

• ShortYandZ(P2,C2)

• ConnectXtogroundrodtobemeasured

• ConnectZtoanelectrode

• Measureasinthethree-pointmethod

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

®


25.4

Grounding conductor

Ground level

Ground rodButt plate

Utility pole

Terminals shortedAuxiliary rod(Y-Z shorted)

Figure 17


4.8 Continuity MeasurementConnecttheshortingstripsbetweenXandXv(C1,P1),andY(P2)andZ (C2).Continuitymeasurementismadewithtwoleads,onefromX–Xv,theotherfromY–Z(P2,C2);pushthe“Measure”buttontomeasure.

Model 3640

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYXC1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 3640



EXPLANATIONS

!

®


Figure 18

Model 4610

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

®


Figure 19


4.9 Soil Resistivity Measurements (Model 4610 Only)

Why make soil resistivity measurements?Soilresistivitymeasurementshaveathreefoldpurpose.First,suchdataareusedtomakesub-surfacegeophysicalsurveysasanaidinidentifyingorelocations,depthtobedrockandothergeologicalphenomena.Second,resistivityhasadirectimpactonthedegreeofcorrosioninundergroundpipelines.Adecreaseinresistivityrelatestoanincreaseincorrosiveactiv-ityandthereforedictatestheprotectivetreatmenttobeused.Third,soilresistivitydirectlyaffectsthedesignofagroundingsystem,anditistothattaskthatthisdiscussionisdirected.Whendesigninganextensiveground-ingsystem, it isadvisable to locate theareaof lowestsoil resistivity inordertoachievethemosteconomicalgroundinginstallation.Resistivitymeasurementsareoftwotypes,thetwopointandthefourpointmethod.Thetwopointmethodissimplytheresistancemeasuredbetweentwopoints.Formostapplications, themostaccuratemethod is thefourpoint method, which is used by the AEMC® Instruments Model 4610GroundTester.Thefourpointmethod,asthenameimplies,requirestheinsertionoffourequallyspaced,andin-line,electrodesintothetestarea.Aknowncurrentfromaconstantcurrentgeneratorispassedbetweentheoutermostelectrodes.Thepotentialdrop(afunctionoftheresistance)isthenmeasuredacrossthetwoinnermostelectrodes.TheModel4610iscalibratedtoreaddirectlyinohms.

b< a20 a a a

Z electrodeY electrodeXv electrodeX electrode

ΩPress ToMeasure

X-Z

Xv-Y

Xv-Y

ZYX XvC1 P1 P2 C2

Fault

Hi Resistance

Hi Noise



!

®


225

Figure 20


4.10 Soil Resistivity Measurement Procedure (4-Point)

Assumingthattheobjectiveislowresistivity,preferenceshouldbegiventoanareacontainingmoistloamasopposedtoadrysandyarea.Consid-erationmustalsobegiventothedepthatwhichresistivityisrequired.• DisconnecttheshortingstripfromtheXandXvterminals.• Arrangetheelectrodesinastraightline.Besurethatdistancesbetween

electrodesare identical:e.g.3metersbetweeneachelectrode(SeeFigure20).

• Thedistancebetweenpolesisproportionaltotheaveragedepthofthesoilsampleyouwishtomake.

• Theelectrodesshouldbeplacedatadepthofapproximately6inches(0.15meters),sothatthedepthisapproximately1/20thofthedistancebetweenelectrodes.

• UseleadstoconnecttheX,Xv,Y,andZelectrodestotherespectiveterminalsontheDigitalGroundResistanceTester.

• Pressthe“Measure”button.• Readtheresistancelevel(R)indicatedonthedisplay.• In the event of difficulties in performingmeasurements, consult the

previousinstructionsconcerninggroundresistancemeasurements.• Applythefollowingformulainordertodetermineresistivity(ρ):

ρ = 2πxRxA A=distancebetweenelectrodesinmeters ρ = resistivity in Ω meters R=ohmsreadingobtainedonModel4610

Example 1: For measurement performed in soil with a high limestone content, the reading is R = 225Ω, with A = 3 meters.

ρ = 2πx225Ωx3m ρ = 4239Ωm

Example 2: After inspection, the area to be investigated has been narrowed down to a plot of ground approximately 75 square feet (22.5m2). Assume that you need to determine the resistivity at a depth of 15 feet (457cm). The distance “A” between the electrodes must then be equivalent to the depth at which average resistivity is to be determined (15 ft, or 450cm). Using the more simplified Wenner formula (ρ = 2πAR), the electrode depth must then be 1/20th of the electrode spacing or 8⅞" (22.5cm). If the electrode depth is greater than 1/20th of the electrode spacing, the following formula must be used:


ρ =4πAR

1 + 2A(A2 + 4B2)

2A(4A2 + 4B2)

Layout theelectrodes inagridpattern (Figure22)andconnect to theModel4610asshowninFigure21.Proceedasfollows:

• RemovetheshortingstripbetweenXandXv• Connectallfourauxiliarygroundelectrodes

Forexample,ifthereadingisR=15,ρ (resistivity) = 2πxRxAA(distancebetweenelectrodes)=450cmρ=6.28x15x450=42,390Ω-cm

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

®


R

B

X Xv Y Z

AA A

Figure 21

AAA

A

A

A

Figure 22


4.11 How to Use 25Ω Calibration CheckerThe calibration checker is good for both the 3640 and 4610. It has aresistance of 25Ω. The procedure to use the calibration checker is asfollows:

• LoosentheX,XV(4610only),YandZterminals.

• InserttheresistorasshowninFigure23.

• TightendowntheterminalsX,XV(4610only),YandZ.

• Pushdownthe“PresstoMeasure”button.

• Compare thereadingon thedisplay to themeasurement rangeprovidedonthelabel.

NOTE: For alignment purposes of the test resistor, it is recommended that the shorting links remain connected between X and XV for the Model 4610, and Y and Z for the Models 3640 and 4610.

Forexample,ifacheckwasperformedontheModel4610or3640,thedisplayshouldshowareadingbetween24.15Ω and 25.85Ω.Ifso(asinFigure23),theinstrumentisingoodworkingcondition.

LO BAT

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYX Xv

C1 P1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 4610



EXPLANATIONS

!

®


3640/461024.15 Ω - 25.85 Ω

460024.05 Ω - 25.95 Ω

362018.75 Ω - 31.25 Ω

25Ω CALIBRATION CHECKER®


LO BAT

ΩPress To

Measure

X-Z

Xv-Y

Xv-Y

ZYXC1 P2 C2

Fault

Hi Resistance

Hi Noise


MODEL 3640



EXPLANATIONS

!

®


3640/461024.15 Ω - 25.85 Ω

460024.05 Ω - 25.95 Ω

362018.75 Ω - 31.25 Ω

25Ω CALIBRATION CHECKER®


Figure 23


CHAPTER 5

MAINTENANCE

5.1 WarningPleasemakesure thatyouhavealready readand fullyunderstand theWARNINGsectiononpage3.

• Toavoidelectricalshock,donotattempttoperformanyservicingunlessyouarequalifiedtodoso.

• Toavoidelectricalshockand/ordamagetotheinstrument,donotgetwaterorother foreignagents into thecase.Turn the instru-mentOFFanddisconnecttheunitfromallcircuitsbeforeopeningthecase.

5.2 Cleaning

NOTE: Disconnect the instrument from any source of electricity.

• Useasoftclothlightlydampenedwithsoapywater.• Rinsewithadampclothandthendrywithadrycloth.

• Donotusealcohol,solventsorhydrocarbons.

5.3 Replacing the Battery• Loosenthetwofasteningscrewsonthebatterycompartmentcover,

whichislocatedonthebottomofthecase(SeeFigure24).

• Removethebatterycompartmentcovertogainaccesstotheeight1.5V“AA”batteries.

• Replacewithnewbatteriesandreassembletheinstrument.


5.4 Replacing the Safety Fuse

NOTE: Do not replace the fuse when the instrument is connected.

To replace the fuse:• Loosen the two fastening screws on the battery compartment

cover,whichislocatedonthebottomofthecase.• Removethebatterycompartmentcovertogainaccesstothefuse

holder.• Replacethefusewiththeappropriatereplacement(0.1A,>250V,

0.25x1.25")andreassembletheinstrument.

! ATTENTIONNE PAS OUVRIR LE BOITIER AVANT D'AVOIRDECONNECTE TOUTES LES ENTREES

! WARNINGDISCONNECT INSTRUMENT FROM ALLINPUTS BEFORE OPENING CASE

SpareFuse

Holders

FuseHolder

Battery CompartmentFastening

ScrewFastening

Screw

Figure 24


Repair and Calibration

Toensurethatyourinstrumentmeetsfactoryspecifications,werecommendthatitbescheduledbacktoourfactoryServiceCenteratone-yearintervalsforrecalibration,orasrequiredbyotherstandardsorinternalprocedures.

For instrument repair and calibration:Youmust contactourServiceCenter foraCustomerServiceAuthorizationNumber(CSA#).Thiswillensurethatwhenyourinstrumentarrives,itwillbetrackedandprocessedpromptly.PleasewritetheCSA#ontheoutsideoftheshipping container. If the instrument is returned for calibration,weneed toknowifyouwantastandardcalibration,oracalibrationtraceabletoN.I.S.T.(Includescalibrationcertificateplusrecordedcalibrationdata).

Ship To: ChauvinArnoux®,Inc.d.b.a.AEMC®Instruments 15 Faraday Drive Dover,NH03820USA Phone:(800)945-2362(Ext.360) (603)749-6434(Ext.360) Fax: (603)742-2346or(603)749-6309 E-mail:[email protected]

(Orcontactyourauthorizeddistributor)Costsforrepair,standardcalibration,andcalibrationtraceabletoN.I.S.T.areavailable.NOTE: You must obtain a CSA# before returning any instrument.

Technical and Sales Assistance

Ifyouareexperiencinganytechnicalproblems,orrequireanyassistancewiththeproperoperationorapplicationofyourinstrument,pleasecall,mail,faxore-mailourtechnicalsupportteam:

ChauvinArnoux®,Inc.d.b.a.AEMC®Instruments 200FoxboroughBoulevard Foxborough,MA02035USA Phone:(800)343-1391 (508) 698-2115 Fax: (508)698-2118 E-mail:[email protected] www.aemc.com

NOTE: Do not ship Instruments to our Foxborough, MA address.


Limited Warranty

TheGroundResistanceTestersModel3640and4610arewarrantedtotheownerforaperiodofoneyearfromthedateoforiginalpurchaseagainstde-fects inmanufacture.This limitedwarranty isgivenbyAEMC® Instruments,notbythedistributorfromwhomitwaspurchased.Thiswarrantyisvoidiftheunithasbeentamperedwith,abusedorifthedefectisrelatedtoservicenotperformedbyAEMC®Instruments.

Full warranty coverage and product registration is available on our website at www.aemc.com/warranty.html.

Please print the online Warranty Coverage Information for your records.

What AEMC® Instruments will do:Ifamalfunctionoccurswithintheone-yearperiod,youmayreturntheinstrumenttousforrepair,providedwehaveyourwarrantyregistrationinformationonfileoraproofofpurchase.AEMC®Instrumentswill,atitsoption,repairorreplacethefaultymaterial.

REGISTER ONLINE AT:www.aemc.com

Warranty Repairs

What you must do to return an Instrument for Warranty Repair: First, request aCustomerServiceAuthorizationNumber (CSA#) by phoneorbyfaxfromourServiceDepartment(seeaddressbelow),thenreturntheinstrumentalongwith thesignedCSAForm.Pleasewrite theCSA#on theoutsideoftheshippingcontainer.Returntheinstrument,postageorshipmentpre-paidto:

Ship To: ChauvinArnoux®,Inc.d.b.a.AEMC®Instruments 15FaradayDrive•Dover,NH03820USA Phone:(800)945-2362(Ext.360) (603)749-6434(Ext.360) Fax: (603)742-2346or(603)749-6309 E-mail:[email protected]

Caution:Toprotectyourselfagainstin-transitloss,werecommendyouinsureyourreturnedmaterial.

NOTE: You must obtain a CSA# before returning any instrument.

11/15

99-MAN100143v18

Chauvin Arnoux®, Inc. d.b.a. AEMC® Instruments15FaradayDrive•Dover,NH03820USA•Phone:(603)749-6434•Fax:(603)742-2346

www.aemc.com

Documents

ENGLISH User Manual - Test & Measurement … GROUND RESISTANCE TESTERS ENGLISH User Manual 3640 4610 Ω Press To Measure X-Z Xv-Y Xv-Y X Y Z C1 P2 C2 Fault Hi Resistance Hi Noise GROUND