test & measurement instruments

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Marina BERHO – Product ManagerMarina BERHO – Product Manager ConfidentialConfidential

Test & Measurement instrumentsTest & Measurement instrumentsTest & Measurement instrumentsTest & Measurement instruments

C.A 6472: Top-of-the-range earth & resistivity testerC.A 6472: Top-of-the-range earth & resistivity tester

C.A 6474 : Earth measurement on pylons with protective C.A 6474 : Earth measurement on pylons with protective cablecable

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The market: segmentationThe market: segmentation

Positioning in the Chauvin Arnoux rangePositioning in the Chauvin Arnoux range

Positioning in relation to the competitionPositioning in relation to the competition

Functional presentation & measurement principleFunctional presentation & measurement principle

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The earth testers marketThe earth testers market

Traditional methods for measuring earth impedance : the 3-pole method and the 4-pole method derived from it.

Advantages : accurate results but following disadvantages:

Necessity of disconnecting the earth,

Necessity of setting up auxiliary rods,

Necessity of sufficient room to set up the rods.

=> often time-consuming and cumbersome.

Other methods available which allow quicker and easier earth measurements

=> selective earth measurement ( only applicable to parallel earthing systems)

These methods are:

The earth clamp

Measurement with 2 clamps

3-pole/4-pole measurement + clamp

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The earth testers marketThe earth testers market

1. Entry-level earth testers (such as the C.A 6423 / C.A 6460 / C.A 6462)

3P / 4P measurement method - Operating frequency 128 Hz

2. Mid-range earth testers (such as the C.A 6470)

• 3P / 4P measurement method - Adjustable measurement frequency to avoid interference voltages

• Measurement expert functions

•Functions for comfortable measurement:

memorization / rechargeable battery / automatic calculation for resistivity

3. Top-of-the-range earth testers (such as the C.A 6472)

• Measurement method: traditional methods with rods + selective methods

• Wide measurement frequency band (up to 5 kHz) to avoid interference voltages and to study the frequency behaviour of an earthing system

• Measurement expert functions: same as C.A 6470

• Functions for comfortable measurement: same as C.A 6470

On the basis of these measurement methods, it is possible to segment the earth testers market as follows:

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Positioning in the Chauvin-Arnoux rangePositioning in the Chauvin-Arnoux rangePositioning in the Chauvin-Arnoux rangePositioning in the Chauvin-Arnoux range

PERFORMANCE

PRICE

C.A 6462C.A 6460

(Earth / Resistivity)

C.A 6410-12-15-15R(Earth clamps)

C.A 6470(Earth / Resistivity)

C.A 6472 / 74(Earth / Resistivity /

Earth of pylons)

C.A 6423(3P earth / digital)

C.A 6421(3P earth / analogue)

C.A 6456(Loop / 1P,2P,3P earth)

Existing products New products

€ 760

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C.A 6472 / C.A 6474: top-of-the range productC.A 6472 / C.A 6474: top-of-the range product

Earth measurement from Earth measurement from 40 Hz to 5 kHz40 Hz to 5 kHz

Multi-function earth and resistivity tester for our expert customers

Measurements possible even in the event of highly resistive soils

Improved measurement quality due to high rejection of interference voltages (up to 60 V)

Excellent accuracy and measurement resolution (up to 0.001 resolution for 4P earth measurement)

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New features compared with the other products of the Chauvin-Arnoux range

Possibility of performing all types of earth measurements with a single instrument

Addition of selective earth measurement functions => possibility of measurement without disconnecting the earthing system

Analysis of behaviour as a function of the frequency due to a wide measurement frequency band (41 Hz to 5 kHz)

Earth measurements on pylons with protective earth cable (with C.A 6474 option)



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Advantages of selective measurement (only suitable for parallel earthing systems)

Earth loop measurement with 2 clamps: principle equivalent to the earth clamp

=> Considerable time-saving as it is not necessary to set up the auxiliary rods and disconnect the earth connection

4P + clamp measurement: accurate selective measurement without disconnecting the earth to be tested

=> No hazards for property and/or people

Advantages of high-frequency measurements:

An earthing system may have an acceptable impedance value at low frequencies, but its behaviour at high frequencies may prove poor due to the inductive effect.

=> Earth measurement with a frequency scan can be used to study the behaviour of an earthing system according to the frequency, thus allowing its behaviour in the event of a fault (e.g. lightning) to be predicted.



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Utility of the expert functionsUtility of the expert functionsUtility of the expert functionsUtility of the expert functions

Measuring the resistances of the auxiliary rods and the interference voltages :

accurate interpretation of the measurements

help users to understand and rectify malfunctions.

1. Measurement of the auxiliary rod resistances

A high rod resistance value influences the measurement accuracy.

Measuring the resistances of the auxiliary rods => find out which one has an excessively high

value.

Possible to remedy this by adding rods in parallel or by wetting the ground.

2. Measurement of interference voltages

Presence of interference voltages => alteration of earth and resistivity measurements.

Measuring these voltages enable to find out the extent of their influence on the

measurement result.

The C.A 6470 & C.A 6472 use a symbol to warn users in the event of significant interference

voltages and include a system for automatically choosing the test frequency with the least

noise.

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TARGET CUSTOMERSTARGET CUSTOMERS

C.A 6472

Major administrations and public services:Major administrations and public services:

SNCF, EDF / RTE and European equivalents, France TELECOMSNCF, EDF / RTE and European equivalents, France TELECOM Inspection organizationsInspection organizations Major electrical installersMajor electrical installers Construction and Civil Engineering implementation industriesConstruction and Civil Engineering implementation industries Maintenance departments in major industriesMaintenance departments in major industries GeologistsGeologists

+ C.A 6474+ C.A 6474

Power transmission companiesPower transmission companies Insurance companiesInsurance companies Telecommunications installers (GSM masts)Telecommunications installers (GSM masts)

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CA 6472: main functionalitiesCA 6472: main functionalitiesCA 6472: main functionalitiesCA 6472: main functionalities

Intuitive use due to the colour-

coded connection terminals also shown on the

screenTest

activation

Connection to C.A 6474

Direct access to functions

•Continuity & 2P/4P resistance measurement,

•Earth: 3P, 4P, 4P+clamp, 2 clamps

•Resistivity

•Potential measurement

•Pylon earth measurement (with C.A 6474)

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Navigation on the instrument:Navigation on the instrument:

A 6-key keyboard for: - CONFIG-FREQUENCY / DISTANCE:Choice of the measurement configuration (2 or 4 wires for continuity measurement, for example) and measurement frequency / input of distances for resistivity calculation - DISPLAY / SMOOTH: new display and access to the supplementary measurement results / activation or deactivation of smoothing on the measurement result display - MEM / MR: storage of the measurement results in the memory / rereading of stored data - / : in general, incrementation / decrementation of the flashing parameter (example: distance to be entered for the ground resistivity calculation)

C.A 6472: main functionalitiesC.A 6472: main functionalitiesC.A 6472: main functionalitiesC.A 6472: main functionalities

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Rugged, leakproof on-site casingRugged, leakproof on-site casing

Compact Compact

Particularly ergonomic Particularly ergonomic large backlit LCD screen rotary switch for direct access to measurements 6-key keyboard marked E-ES-S-H input terminals

Battery rechargeable on mains Battery rechargeable on mains oror vehicle cigarette lighter vehicle cigarette lighter

APPEARANCE APPEARANCE

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Large LCD screenLarge LCD screen

- backlit- backlit

- 3 simultaneous digital display levels for more information- 3 simultaneous digital display levels for more information

- wide range of symbols and indicators- wide range of symbols and indicators

APPEARANCE APPEARANCE

Example:

The connection terminals are shown on the display; one is not connected although the measurement selected requires it , so it is flashing

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3 operating modes:- Automatic mode in each function; by default, the instrument performs a measurement at 128Hz and chooses the most appropriate frequency in the event of interference voltages.

A single key is all you need for easy handling:

- selection of a function

- press on the START button

- reading of the result

-Scan mode (automatic measurements at different frequencies) allowing a graph of impedance (automatic measurements at different frequencies) allowing a graph of impedance as a function of frequency to be plottedas a function of frequency to be plotted

-Manual mode (choice of the measurement frequency, display of all the voltages measured, (choice of the measurement frequency, display of all the voltages measured, etc.) for expert customersetc.) for expert customers

Easy to useEasy to use

Colour-coded terminals for simpler connections

Reduction in handling errors due to automatic detection of incorrect connections: E, ES, S and H flash on the display if the connection is incorrect

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CONTINUITY MEASUREMENT CONTINUITY MEASUREMENT ( position) ( position)

Advantages of this type of measurement:Advantages of this type of measurement:Verification of:Verification of:- the condition of the measurement cablesthe condition of the measurement cables- the connections between the measurement cables and the measurement rodsthe connections between the measurement cables and the measurement rods- the interlinks in a parallel earth networkthe interlinks in a parallel earth network

Characteristics:Characteristics:

- methods : 2 wires or 4 wires (compensation of leads possible with 2-wire method)- methods : 2 wires or 4 wires (compensation of leads possible with 2-wire method)

- possibility of reversing the measurement current and calculating the average- possibility of reversing the measurement current and calculating the average

- resistance range: 0.001 - resistance range: 0.001 to 100 k to 100 k- measurement current: 200 mA for R - measurement current: 200 mA for R < < 20 20

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EARTH MEASUREMENT WITH EARTH MEASUREMENT WITH 3P METHOD ( position)3P METHOD ( position)

The 3P method is the traditional rod method for accurately measuring the resistance The 3P method is the traditional rod method for accurately measuring the resistance of an existing earth connection.of an existing earth connection.

Characteristics:Characteristics:

• resistance range Rresistance range REE : 0.01 : 0.01 to 100 k to 100 k

• adjustable measurement voltage: 16 or 32 Vrmsadjustable measurement voltage: 16 or 32 Vrms• adjustable measurement frequency: 41 to 5,078 Hzadjustable measurement frequency: 41 to 5,078 Hz

• RRSS and R and RHH : measurement from 0.1 : measurement from 0.1 to 100 k to 100 k

• max. Umax. Uinterferenceinterference 60 V 60 Vpeakpeak

Selection of the frequency:Selection of the frequency:-This can be done manually (if the user knows a frequency where the interference voltages This can be done manually (if the user knows a frequency where the interference voltages will be minimal) or in will be minimal) or in automatic modeautomatic mode (the instrument makes the selection). (the instrument makes the selection).

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EARTH COUPLING MEASUREMENT EARTH COUPLING MEASUREMENT ( position)( position)

Characteristics: Characteristics: the same as the previous the same as the previous measurementsmeasurementsAdvantages of the measurement:Advantages of the measurement:- To estimate the reciprocal influence of 2 earth - To estimate the reciprocal influence of 2 earth resistances which are not connected to one resistances which are not connected to one another, the coupling coefficient must be another, the coupling coefficient must be calculated.calculated.- This coefficient should be as low as possible.- This coefficient should be as low as possible.- In concrete terms, the aim is to prevent a - In concrete terms, the aim is to prevent a possible fault current flowing in the 1st earth from possible fault current flowing in the 1st earth from raising the potential of the 2nd earth.raising the potential of the 2nd earth.This type of measurement involves carrying This type of measurement involves carrying out successive measurements:out successive measurements: Two earth resistance measurements with Two earth resistance measurements with the 3P method ("3 poles" position)the 3P method ("3 poles" position) One 2P resistance measurement ("2 poles" One 2P resistance measurement ("2 poles" position)position)

After these 3 measurements, the After these 3 measurements, the instrument instrument automatically calculates automatically calculates the coupling resistance Rc.the coupling resistance Rc.

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RESISTIVITY MEASUREMENT ( position)

Advantages of the measurement:Advantages of the measurement:Assessment of the terrain Assessment of the terrain - to choose the best position for construction of the earth or earth networkto choose the best position for construction of the earth or earth network- to optimize the construction costs and save time when seeking the required earth resistance.to optimize the construction costs and save time when seeking the required earth resistance.

Characteristics:Characteristics:- resistance range R- resistance range RS-SES-SE : 0.01 : 0.01 to 100 k to 100 k- adjustable measurement voltage: 16 or 32 Vrms- adjustable measurement voltage: 16 or 32 Vrms- adjustable measurement frequency: 41 to 128 Hz- adjustable measurement frequency: 41 to 128 Hz- rod resistances R- rod resistances REE, R, RESES, R, RSS and R and RHH: measurement from 0.01 ohms to 100 k: measurement from 0.01 ohms to 100 k - Maximum U- Maximum Uinterferenceinterference 60V 60Vpeakpeak

The C.A 6472 automatically The C.A 6472 automatically calculates the resistivity rcalculates the resistivity r (Wenner or Schlumberger (Wenner or Schlumberger method) as soon as the distances used for the measurement have been method) as soon as the distances used for the measurement have been programmed.programmed.

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RESISTIVITY MEASUREMENT ( position)

The Wenner & Schlumberger methodsThe Wenner & Schlumberger methodsWenner

- the distances between the 4 rods are identical: d

- W = 2..d.RS-ES

Schlumberger

- the distance between the 2 outer rods is 2d- the distance between the 2 inner rods is A

- S = (.(d²-A²/4).RS-ES) / 4

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GROUND POTENTIAL MEASUREMENTGROUND POTENTIAL MEASUREMENT

• Lightning: 2 dangers

- Risk of direct strike on an individual or installation

- Risk of electrification when it strikes close to a person due to the step voltage caused by the lightning.

• Principle:

The current source created at the point of impact causes an electrical field

=> Voltage on the ground which varies according to the distance from the source

=> a difference in potential, or step voltage, occurs between two different points in contact with the ground, increasing with the size of the step.

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GROUND POTENTIAL MEASUREMENTGROUND POTENTIAL MEASUREMENT

AdvantagesAdvantages:: Determination of the ground potential value according to the distanceDetermination of the ground potential value according to the distance This measurement can be used to obtain a theoretical step voltage This measurement can be used to obtain a theoretical step voltage

value and to determine the region where the potential rise will be the value and to determine the region where the potential rise will be the lowest in the event of faults.lowest in the event of faults.

Measurement principle:

Technical characteristics:Technical characteristics:

Resistance range R S-SE: Resistance range R S-SE: 0.01 0.01 to 100 k to 100 k Voltage measurement range:Voltage measurement range: 0.01 mV to 32 V 0.01 mV to 32 V Voltage generated in open circuit: Voltage generated in open circuit: 16 or 32 Vrms16 or 32 Vrms Adjustable measurement frequency: Adjustable measurement frequency: 41 Hz to 41 Hz to

5,078 Hz5,078 Hz Measurement of RS and RH: Measurement of RS and RH: 0.1 0.1 to 100 k to 100 k

maximummaximum Maximum Uinterference: Maximum Uinterference: 60 Vpeak60 Vpeak

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4P EARTH MEASUREMENT4P EARTH MEASUREMENT

Based on the same principle as the 3P method

Provides 10 times greater measurement accuracy on the C.A 6472 Method particularly suitable for measuring very low earth resistancesVery useful for power transmission companies & distributors of electricity

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SELECTIVE 4P EARTH MEASUREMENTSELECTIVE 4P EARTH MEASUREMENT

Applicable in the case of several resistances set up in parallel

Principle: Measurement of the current flowing in the considered earth thanks to a clamp-on ammeter

This "selective 4P" measurement method provides:

Considerable time savings because it is no longer necessary to disconnect the earth resistance to be measured. Indeed, with the clamp, it is possible to measure the current flowing in the earth connection to be tested, thus removing the influence of the parallel earth connections.

Guaranteed safety for the goods and people in contact with the electrical installation because the earth is not disconnected.

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Technical characteristics:Technical characteristics:

Resistance range R E: Resistance range R E: 0.001 0.001 to 100 k to 100 k Voltage generated in open circuit: Voltage generated in open circuit: 16 or 32 Vrms16 or 32 Vrms Adjustable measurement frequency: Adjustable measurement frequency: 41 Hz to 5,078 Hz41 Hz to 5,078 Hz Measurement of RS and RH: Measurement of RS and RH: 0.1 0.1 to 100 k to 100 k maximum maximum Maximum Uinterference: Maximum Uinterference: 60 Vpeak60 Vpeak

4P AND SELECTIVE 4P 4P AND SELECTIVE 4P EARTH MEASUREMENTEARTH MEASUREMENT

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EARTH LOOP MEASUREMENT WITH 2 CLAMPS

Measurement principleMeasurement principle

Placing 2 clamps around the earth conductor tested and connecting each of them to the

Instrument

=> 1 clamp injects a known signal ( 32 V / 1,367 Hz) while the other clamp measures the current flowing in the loop.

This method is based on the same principle as the earth clamp..

AdvantagesAdvantages

This method saves considerable time during earth testing because it is no longer

necessary to:

- set up auxiliary rods

- disconnect the earth connections, which is often time-consuming.

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EARTH LOOP MEASUREMENT WITH 2 CLAMPS

Technical characteristics:Technical characteristics:- Resistance range R E: Resistance range R E: 0.20 0.20 to 500 to 500 - ResolutionResolution: 0.01 : 0.01 to 1 to 1 - AccuracyAccuracy: : +/- (5% + 1pt)+/- (5% + 1pt)

- - Adjustable measurement frequency: Adjustable measurement frequency: 1,367 Hz, 1,611 Hz, 1,758 Hz1,367 Hz, 1,611 Hz, 1,758 Hz

R = R E + ( RE1 // RE2 // RE3 // ... // REn )

Negligible compared with R E

Caution:

This method is only applicable if there is a path of low impedance parallel to the connection tested.

It is therefore recommended to evaluate the equivalent resistance of the n connections in parallel and ensure that the value is genuinely negligible compared with R E.

Measurement set-up

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Advantages of measurements at high Advantages of measurements at high frequenciesfrequenciesAdvantages of measurements at high Advantages of measurements at high frequenciesfrequencies

By increasing the frequency of the measurement current, the inductances can be By increasing the frequency of the measurement current, the inductances can be

"saturated" and the resistance to be measured can be isolated."saturated" and the resistance to be measured can be isolated.

Example 1: earth measurement with TN system

Equivalent diagramEquivalent diagram

3P method with a classic 128 Hz frequency

The parallel set-up of the resistances is measured.

Indeed, a large proportion of the current injected flows in the other loops via the PEN wire.

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Advantages of measurements at high Advantages of measurements at high frequenciesfrequenciesAdvantages of measurements at high Advantages of measurements at high frequenciesfrequencies

High-frequency 3P methodZ PEN becomes infinitely large and this prevents the current from flowing

The entire current injected flows to the earth Re

The value of Re is measured rather than the parallel set-up of the resistances.

Example 2: Check that the resistance value measured really is the value of the earth under consideration rather than the result of the parallel set-up of several earths.

Indeed, 3P or 4P earth measurement requires disconnection of the earth bar.Indeed, 3P or 4P earth measurement requires disconnection of the earth bar.

In some cases, the earthing system is complex and users are not necessarily aware In some cases, the earthing system is complex and users are not necessarily aware

of all the earth connections which they want to measure.of all the earth connections which they want to measure.

frequency

Resistance In scan mode, if it is observed that the resistance varies In scan mode, if it is observed that the resistance varies according to the frequencyaccording to the frequency

=> the object measured is not purely resistive=> the object measured is not purely resistive

=> the earth measured is in fact connected to another.=> the earth measured is in fact connected to another.

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COMPETITION

The C.A 6472 is the only instrument on the market which can simultaneously:

- Carry out earth measurements using all the measurement methods

- Carry out high-frequency earth measurements

- Carry out earth measurements on pylons with a protective earth cable(with C.A 6474 option)

To define its positioning in relation to the market, it must therefore be compared with various types of products:

- "multi-method" earth testers

- variable-frequency earth testers

- high-frequency earth testers

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C.A 6474 option: Earth measurement on C.A 6474 option: Earth measurement on pylons with protective earth cable pylons with protective earth cable

Pylons are linked together by a cable called the "protective earth cable" to drain any currents to earth; a high-voltage line is therefore equivalent to a parallel earthing system.

Rpylon

L L L L

Equivalent diagram

Problem: Measuring the earth of a pylon without including the earthing of the other pylons in parallel.

The traditional (3P-type) methods require disconnection of the protective earth cable, which is dangerous and time-consuming.

Earth cable

High-voltage

lines

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C.A 6474 option: Earth measurement on C.A 6474 option: Earth measurement on pylonspylons

Solution: C.A 6474

Carry out selective earth measurement on the pylons without disconnecting the protective earth cable

Equivalent measurement to a selective measurement with clamps, but replacing the clamps with Ampflexes

Use of flexible sensors = any shape of earthing system can be "clamped", unlike with current clamps which are limited by their clamping diameter.

Measurement concept with Ampflexes can therefore be applied to all types of pylon geometries or to earthing systems which are not "traditionally-shaped"; This measurement principle can thus be extended to other types of pylons (GSM masts, etc)

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Measurement contextMeasurement context

Rpylonl

L L L L

Pylon measured

Earth cable

Current injection

point

Equivalent diagram of a high-voltage line:

EQUIVALENT A

Rpylonl

Pylon measured

ZequivalentZequivalent

A traditional 4P measurement cannot yield consistent results when measuring the earth of a pylon.

Indeed, much of the current injected flows via the protective earth cable (because it is not very resistive) so the measurement does not give the earth impedance value of the pylon earth under consideration, but the value for the whole of the line.

There are two solutions for measuring only the earth resistance of a specific pylon:

-either directly measuring the value of the current flowing via the pylon earth to be measured, i.e. carrying out a selective measurement

-or reducing the current diverted via the protective earth cable to a negligible value

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PYLON EARTH MEASUREMENTPYLON EARTH MEASUREMENT

The C.A 6474 combines both principles, so it can be used for accurate selective earth measurements on pylons:

The use of Ampflexes => precise measurement of the current flowing in the pylon

A high-frequency measurement => a Zeq value much higher than the earth resistance value to be measured

the current diverted via the protective earth cable to the other pylons becomes negligible and the value of the current flowing via the earth rises

better accuracy of the measurement.

2 methods of measurement with C.A 6474:

Active method, i.e. with injection of a measurement current by the C.A 6472

Passive method using the residual currents flowing in the high-voltage line

2 advantages for the passive method:

- enable to check the consistency of the measurements obtained with the active method

- ensures that measurement results can be obtained whatever the conditions; indeed, highly resistive ground may prevent a sufficient measurement current from flowing, so that the active method cannot be used.

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Why choose a maximum frequency Why choose a maximum frequency of 5 kHz?of 5 kHz?

Utilitiy of high-frequency earth measurement :

• to measure the earth resistance of pylons equipped with a protective earth cable

• to forecast the behaviour of an earthing system in the event of lightning.

Frequency of lightning may be up to 1 MHz, but most of the energy is located between 5 and 30 kHz

=> Why the C.A 6472 + C.A 6474 is limited to a 5 kHz measurement frequency?

The C.A 6474 measurement concept was developed in close liaison with RTE, the pylon earth measurement specialists in France.

This 5 kHz frequency has been approved by RTE as the frequency providing the best trade-offs between:

- the error on the measurement instruments' accuracy

- the gain on the ratio of injected current/current in the pylon: indeed, the aim is obtain a sufficient earth current value for accurate earth measurement.

- capacitive leakage due to the high frequency

Measurements up to 5 kHz allow extrapolation of the values up to 30 kHz

=> Prediction of the earthing system's behaviour in the event of lightning.

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As well as pylon earth measurements, the C.A 6474 can be used to carry out the following measurements:

• Measurement of the impedance of the entire line according to the frequency

the line's behaviour in the event of lightning can be predicted;

Indeed, in the event of lightning, the line's impedance must be sufficiently low to allow the fault currents to flow via the protective earth cable and be diverted to earth via the pylons.

• Quality of protective earth cable connection:

as the fault currents are diverted via the protective earth cable and then via the pylons, the connection between the two elements must be good.

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Test no.3: Selective measurement with the C.A 6474 with frequency scan

Test no. 1: 4P method with a "traditional" measurement frequency of 128 Hz

Result: R = 2

Example of measurement:

Let us consider a network of 10 pylons in which each pylon has an earth resistance of 10

Test no.2: 4P method with a frequency scan from 41 Hz to 5,078 Hz

Test no. 4: Measurement of the impédance of the line with frequency scan

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Interpretation:Interpretation:

1. traditional 4P measurement does not allow the genuine earth resistance of the pylon under consideration to be measured

=> a 4P earth measurement at 128 Hz gives an earth resistance of 2 instead of 10 .

2. The traditional 4P method with a frequency scan can be used to gain a rough idea of the real earth resistance value: it is a way of checking the pertinence of the results obtained with the AmpFlex method.

3. Selective measurement with the C.A 6474: the measurement does not depend on the measurement frequency; it therefore really is the earth value of the pylon considered (purely resistive) which is measured.

4. Measurement of the line impedance and assessment of protective earth cable connection quality: in the case studied here, the curve representing the line impedance value according to the frequency has no point of inflexion. This means that the impedance will be infinitely large in the event of a fault and will not therefore convey the fault currents in the event of lightning => this line is therefore dangerous.

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Technical specifications:Technical specifications:

Resistance range RE : Resistance range RE : 0.01 0.01 to 100 k to 100 k Voltage generated in open circuit: Voltage generated in open circuit: 16 or 32 Vrms16 or 32 Vrms Adjustable measurement frequency: Adjustable measurement frequency: 41 Hz 41 Hz

to 5,078 Hzto 5,078 Hz RS and RH measurement: RS and RH measurement: 0.1 0.1 to 100 k to 100 k

maximummaximum Maximum Uintereference: Maximum Uintereference: 60 Vpeak60 Vpeak


When used with a vectorial processing unit (C.A 6474), the C.A 6472 When used with a vectorial processing unit (C.A 6474), the C.A 6472 can be used to measure the earth of pylons with protective earth can be used to measure the earth of pylons with protective earth cables.cables.

Using 4 Ampflex current sensors positioned around the pylon Using 4 Ampflex current sensors positioned around the pylon footings and a frequency scan up to 5 kHz, the earth impedance of footings and a frequency scan up to 5 kHz, the earth impedance of the pylon considered can be measured precisely and selectively.the pylon considered can be measured precisely and selectively.

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1. Place auxiliary electrodes H and S on opposite sides of the pylon,as far away as possible and, if possible, perpendicular to the high-voltage line

This will eliminate interference with the measurement by spurious voltages or currents induced under the highvoltage line.

MAKING A MEASUREMENTMAKING A MEASUREMENT

To validate the principle of measurement, we made many field measurements with RTE, specialist in earth measurement of pylons.

2. In order to avoid electromagnetic interference:

•unwind the full length of each cable from the reel

•keep the cables as far apart as possible on the ground

•take care not to form loops

•avoid placing the cables near or parallel to metallic conductors (cables, rails, fences, etc.).

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3. Connections:

• Connect the electrodes to terminals H and S.

• Connect ES and E a conducting metallic part of the pylon located above the AmpFLEX sensors.

• Connect the required number of AmpFLEX sensors to channels 1, 2, 3, and/or 4 (the channels for which they are calibrated) and place the AmpFLEX loop(s) around the legs of the pylon.

• Connect the C.A 6472 and the C.A 6474 together

Attention:

• All of the AmpFLEX loops must be oriented in the same direction and they must all have the same number of turns.

• Do not move or touch the AmpFLEX sensors during the measurement, because that might cause errors.

MAKING A MEASUREMENTMAKING A MEASUREMENT

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MEASUREMENT WITH AMPFLEXMEASUREMENT WITH AMPFLEX

According to the position of the AmpFlex in relation to the current injection cable on the pylon, the measurements carried out are different:

1. AmpFlex below current injection:

Rs

Injection point

In this configuration, the AmpFlex measures the

current flowing to earth I 2

The current measured can therefore be used to obtain the earth resistance value of the pylon considered.

Rs

Injection point

2. AmpFLex above current injection

In this configuration, the AmpFlex measures the difference between the current injected and the current flowing to earth

The current measured is the current flowing via the top of the pylon and the protective earth cable

This measurement can therefore be used to measure the line impedance.

I 1

I 2

I 1

I 2

I injected =I 1 + I 2

I measured = I 2

I injected =I 1 + I 2

I measured = I injected - I 2 =I 1

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Summary: Product advantages of the CA6472/6474

Earth measurement whatever the configuration Possibility of measurement without disconnecting the earth bar Wide measurement frequency band: 40 Hz – 5 kHz40 Hz – 5 kHz High rejection of interference voltages Measurement of U h-e, U s-e and Ies interference voltages / currents for

better interpretation Possibility of earth measurement whatever the configuration Earth measurement on pylons with protective earth cable:- All types of pylons due to the use of flexible sensors - Accurate, pertinent measurements due to the possibility of measuring at

high frequencies Simple, intuitive use

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SALES TOOLS

SALES LITTERATURE

POSTER

APPLICATION NOTES

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Accessories

• C.A 6474 adapter for pylon earth measurement (PYLON BOX) ...............................P01.1265.10• MN82 clamp for C.A 6472 .......................................................................................P01.1204.52• Adapter for battery charging on vehicle cigarette lighter ...................................... P01.1020.36• Optical / RS communication cable...........................................................................P01.2952.52 • Earth & resistivity kit (100 m / 150 m)

C.A 6472 earth and resistivity tester ............................…………………………….……..P01.1265.04

Delivered with:

• Battery charger

• Operating manual in 5 languages on CD-ROM,

• Simplified operating instructions

• Data export software

• Optical / USB communication cable

• 2 x C182 clamps

State of deliveryState of delivery

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C.A 6474 adapter for pylon earth measurement (PYLON BOX) .................................P01.1265.10Delivered with a carrying bag for accessories containing:• 1 C.A 6472 – C.A 6474 connection cable,• 6 BNC / BNC cables 15 m long for linking the AmpFlexes to the CA6474• 4 flexible current sensors (AmpFLEX) 5 m long,• 1 set of 12 identification rings for AmpFLEX flexible sensors• 2 cables (5 m green, 5 m black) with safety plugs on winder (cables linking the pylon to the C.A 6472)• 5 spade lug/banana plug adapters, Ø 4 mm,• 3 adjustable clamps: fastening of the cables on the pylon• 1 calibration loop,• Descriptive label

State of delivery: C.A 6474State of delivery: C.A 6474

C.A 6472 / C.A 6474 connection

cable

AmpFlex

MN82 clamp

C182 clamp

BNC cable

Adjustable clamp

Bureau.scf

MAE-F, 11/2006 - 48


C.A 6474 adapter for pylon earth measurement (PYLON BOX) ...........................P01.1265.10Delivered with a carrying bag for accessories containing:• 1 C.A 6472 – C.A 6474 connection cable,• 6 BNC / BNC cables 15 m long for linking the AmpFlexes to the C.A 6474• 4 flexible current sensors (AmpFLEX) 5 m long,• 1 set of 12 identification rings for AmpFLEX flexible sensors• 2 cables (5 m green, 5 m black) with safety plugs on winder (cables linking the pylon to the C.A 6472)• 5 spade lug/banana plug adapters, Ø 4 mm,• 3 adjustable clamps: fastening of the cables on the pylon• 1 calibration loop,• Descriptive label

State of delivery: C.A 6474State of delivery: C.A 6474

Adjustable clamps

AmpFlex

test & measurement instruments

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