Wee MEGGER® Te s t e rW M 6

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MEGGER ®

SAFETY WARNINGS

The circuit must be de-energized and isolated BEFORE connections are made for any test.

Do not touch the circuit during an insulation test.

After insulation tests, capacitive circuits MUST be allowed to discharge BEFORE disconnecting the test leads.

Test leads, including prods and crocodile clips, must be in good order; clean and having no broken or cracked insulation.

Replacement fuses must be of the correct type and rating.

Refer also to page 8 for further explanations and other precautions.

The warnings and precautions must be read and understood before theinstrument is used. They must be observed during use.

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NOTE

This instrument must only be used by suitably trained and competent persons.

CONTENTS

Safety Warnings 2

General Description 4

Applications 4

Specification 5

Accessories 7

Operation 8Warning 8Preliminary checks 8Fuse replacement 8Insulation testing 9Continuity testing 9

Using the Insulation Tester 10Preventive maintenance 10Insulation Testing concepts 11

Mode d’Emploi 12

Betriebsanleitung 14

Instrucciones de Uso 16

Setting-up Procedure 18

Repair and Warranty 19

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GENERAL DESCRIPTION APPLICATIONS

The WM6 MEGGER® Insulation and Continuity Testeris a completely self contained instrument designed togive rapid and accurate measurement of insulationresistance and continuity resistance.

The WM6 uses a low voltage hand-cranked a.c.brushless generator as the power supply. Thisgenerator is easy to turn and is connected to arectifier and d.c. to d.c. converter to provide the testvoltage.

The WM6 uses a moving coil meter with taut bandsuspension, white scales on a black scale plate andan orange ‘dayglow’ pointer. An electronic circuit isemployed to produce a four decade calibrated scalefor insulation resistance measurement from 0 to 200 MΩ.

Two shrouded sockets are provided in the side of thecase for the test leads and a slider switch selectseither insulation or continuity tests (‘MΩ’ or ‘Ω’). Thecase is robust, made of ABS plastic, and thegenerator handle folds neatly against it when not inuse.

The WM6 is intended for the direct measurement ofinsulation resistance and continuity of domestic andindustrial wiring, cables, transformers, motors,generators, electrical machinery and appliances.Because the WM6 is self-powered it is suitable foruse during installation and commissioning work aswell as for service and maintenance applications.

Note:— The cover of this instrument has been givenan antistatic treatment which should beeffective for many months. If in the course oftime the cover is found to retain electrostaticcharges, it should be re-treated with asuitable antistatic solution.

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SPECIFICATION

WM6Ranges insulation 0–200 MΩ and ∞

continuity 0–100 Ω

Terminal Voltage insulation range <600 Von Open Circuit (d.c.) continuity range 800 mV approx.

Terminal Voltage at insulation range 500 V + 10% –5%1 M Load (d.c.)

Terminal Current insulation range 1,3 mA approx.on Short Circuit continuity range 55 mA approx.

Voltage Stability insulation range <±1%160 r.p.m. to 240 r.p.m.

Ripple Content at 160 r.p.m. insulation range 500 mV pk-pk approx.on Open Circuit

Accuracy 1,5 mm (0,060 in) from any marked position on thescale when measured against standard resistors.

Temperature operating –10 °C to +50 °Cstorage –20 °C to +70 °C

Flash Test 2,3 kV a.c. r.m.s.

Voltage Source (d.c.) Brushless a.c. hand-cranked generator with rectifier and d.c. to d.c. converter.

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SPECIFICATION

Fuse 1 A 20 x 5 mm ceramic

Dimensions 131 x 98 x 61 mm (51/8 x 37/8 x 23/8 in)

Weight 650 g (1 lb 7 oz)

Terminal Voltage Characteristics

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WM6Ω

SPECIFICATION ACCESSORIES

Illustrations of Typical Scales (full size)

WM6

SUPPLIED WITH THE INSTRUMENT

Test lead set including shrouded crocodile clips

User Guide Part No. 6171-685

Test Record Card (5 supplied) Part No. 6172-111

AVAILABLE AS AN OPTIONAL EXTRA

A leather ‘test-and-carry’ case with a specialcompartment for test leads Part No. 6420-088

Test Lead set red/black Part No. 6220-437

Test Record Card (Pack of Twenty) Part No. 6111-216

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OPERATION

W A R N I N G1 . The circuit under test m u s t be de-energized and

isolated before insulation or continuity tests arem a d e .

2 . When capacitive circuits have been tested allow asuitable time to elapse before disconnecting thetest leads, for the circuit to discharge.

3 . Instruments used in dusty environments should bestripped and cleaned periodically.

4 . Do not leave the instrument exposed to direct heatfrom the sun for long periods.

5 . The instrument circuit contains a static sensitivedevice. If the instrument casing is opened for anyreason (this will automatically invalidate anywarranty covering the instrument), care must beexercised in handling the printed circuit board.This should be done in accordance with DEFSTAN 59-98 and BS 5783 specifications forhandling electrostatic sensitive devices. Printed circuit boards containing such devices areidentified either by a yellow warning label or by ayellow legend and a large yellow dot on the p.c.b.(Initially the dot may not be included.)

PRELIMINARY CHECKSInspect the test leads to see that they have goodunbroken insulation. Connect the red and black leads,terminated with the clips, to the red (+) and black (–)terminal sockets respectively in the side of theinstrument case. Leave the leads coiled or twistedtogether, but ensure that their clips are not touchinganything. Set the slider switch to the ‘MΩ’ position.Turn the generator handle at approximately 160 r.p.m.and observe the meter pointer, it should rest over the‘∞’ (infinity) position on the scale. If it does not the testleads may be faulty and should be inspected moreclosely for damage. Replace them if necessary.

Connect the test lead clips together and turn thegenerator handle again, the meter should read zero. If it indicates infinity or a high resistance value theleads may be open circuit and should be inspectedfurther, replace if necessary. Shorting the leadstogether and obtaining a zero reading also proves thatthe instrument is working.

To check that the fuse in the continuity circuit is intact,leave the test leads connected together and set theslider switch to the ‘Ω’ position. Turn the generatorhandle again, the reading obtained should be zero (orvery nearly so). If the reading is beyond full scale onthe ‘Ω’ range the fuse has ruptured and should ber e p l a c e d .

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FUSE REPLACEMENTThe fuse is held in a screw-type holder. To change afuse, use a screwdriver to release the centre part ofthe holder containing the fuse. Replace with a 1 A 20 x 5 mm ceramic fuse part no. 25413-286. Analternative fuse should not be used as the fuseresistance will affect the lower continuity readings.

INSULATION TESTINGAfter connecting the test leads to the instrument andmaking the preliminary checks as detailed above, setthe slider switch to ‘MΩ’. With the circuit to be testedisolated, connect the test leads as follows:—( a ) for insulation tests to earth —

connect the red lead to earth or frame of theequipment, and the black lead to that part of thecircuit to be tested.

( b ) for insulation tests between wires —connect a lead to the core of each of the wires.

Turn the generator handle at between 160 r.p.m. and240 r.p.m. The meter pointer will indicate the value ofinsulation resistance on the ‘MΩ’ scale. (If a capacitivecircuit is tested the pointer will initially deflect towardszero and then gradually rise to its final steady value asthe capacitance is charged up to the output voltage ofthe tester.)

If several successive readings of ‘∞’ are obtained,connect the two further ends of the test leads togetherand turn the generator handle. A zero reading shouldresult which double checks that the leads are notdisconnected or broken and therefore the insulationresistance readings are correct.

Capacitive circuits automatically discharge throughthe tester when the generator handle stops rotating.The meter pointer will deflect beyond the ‘∞’ positionon the scale and then return to its normal rest positionat ‘∞’ when the circuit has discharged. Wait a fewmoments for this to happen before disconnecting thetest leads. The discharge time (to 0 V) is approx. 8seconds per microfarad.

CONTINUITY TESTINGWith the test leads connected to the instrument, andhaving checked them and the fuse as describedabove, set the slider switch to the ‘Ω’ position. With thecircuit under test isolated, connect the test leadsacross the appropriate points and turn the generatorhandle at between 160 r.p.m. and 240 r.p.m. Theresistance will be indicated on the ‘Ω’ scale. Thisresistance includes that of the test leads which shouldbe measured separately, (by performing a test withthe clips joined together), and the result deductedfrom the total.

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Preventive MaintenanceThe proverb ‘A stitch in time saves nine’ inspired thetitle of an AVO International booklet on insulationtesting, as it neatly sums up the benefits ofpreventative maintenance. The savings come infinancial terms from costly repairs, lost production, lostprofits and in human terms, from lives saved in theevent of dangerous electrical faults.

Regular insulation testing of electrical equipment canhelp to detect deteriorating insulation. The effectswhich cause insulation to deteriorate includemechanical damage, vibration, excessive heat or cold,dirt, oil, moisture and localized voltage stresses - all ofwhich can arise on most industrial or utility equipment.

Insulation tests are sometimes used in isolation asabsolute measures of the quality of the insulation. Thisis most appropriate when equipment is being installedand checked for compliance with a specified ‘Pass’level. For operational equipment the key factors aretrends in the insulation readings.

It is therefore important that records of insulationreadings are kept, relating to each piece of equipmentor ‘Asset’ in your testing regime. AVO Internationalsupplies test record cards to assist with such recordkeeping. There are also a number of influences on theinsulation readings - temperature, humidity andsurface leakage for example and a range of testtechniques have been developed to help with theinterpretation of your insulation tests.

10Test Record Example

Insulation Testing ConceptsInsulation resistance can be considered by applyingOhm’s Law. The measured resistance is determined fromthe applied voltage divided by the resultant current, V

R = I There are two further important factors to be considered.These are:( i ) the nature of the current through and/or over the

insulation, and :( i i ) the length of time for which the test voltage is applied.

These two factors are linked. The total current that flows is made up of three separatec u r r e n t s : -

1 . Capacitance charging current. This current is initiallyhigh and drops as the insulation becomes charged upto the applied voltage.

2 . Absorption current. This current is also initially high but drops at a much slower rate than the chargingc u r r e n t .

3 . Conduction or Leakage current. This is a smallsteady current that can be sub-divided into two:-(a) A current flowing along conduction paths through

the insulation material.(b) A current flowing along conduction paths over the

surface of the insulation material.As the total current depends upon the time for which thevoltage is applied, Ohm’s Law theoretically applies at infinite time. The charging current falls relatively rapidly as theequipment under test becomes charged up. The actuallength of time depends upon the size and capacitance ofthe item under test. Larger items with more capacitance will take longer e.g.long supply cables. The absorption current decreasesrelatively slowly compared with the charging current. Inessence it depends upon the nature of the insulation material. The conduction or Leakage current builds upquickly to a steady value and then remains constant for aparticular applied voltage under stable conditions. It is thiscurrent that is affected by moisture, dirt etc. and thedegree to which it flows bears a direct relation to thequality of the insulation, and consequently to the value ofthe insulation resistance measured. An increase in theleakage current is a pointer to possible future problems.

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MODE D’EMPLOI

A V E R T I S S E M E N T S1 ) Le circuit à essayer doit être mis hors tension et

isolé, préalablement à toute mesure.2 ) Après l’essai de circuits capacitifs, attendre le

temps nécessaire à la décharge avant de retirerles cordons de mesure.

3 ) Les appareils utilisés dans les environnementspoussiéreux doivent être démontés et nettoyésp é r i o d i q u e m e n t .

4 ) Ne pas laisser l’appareil trop longtemps exposé aus o l e i l .

VERIFICATIONS PRELIMINAIRESVérifier si l’isolement des cordons de mesure estcorrect. Pour ce, brancher les cordons rouge et noir,munis de leur pince crocodile, dans les bornes rouge(+) et noire (–) de l’appareil.

Torsader ensemble les deux cordons et s’assurer queleurs extrémités ne sont pas en contact. Placer lecommutateur de gamme sur “MΩ”. Tourner lamanivelle du générateur à environ 160 tours parminute et controler que l’aiguille de l’indicateur seplace sur la position “∞” de l’échelle. Si ce n’est pasle cas, il faut vérifier minutieusement l’état des cordonset les remplace si nécessaire.

Court-circuiter les pinces crocodiles et actionner ànouveau la manivelle. L’aiguille de l’indicateur doit se

placer sur le zéro de l’échelle. En cas d’indication derésistance de valeur élevée (ou position ‘∞’) lescordons sont peut-être coupés. Vérifier leur état et lesremplacer si nécessaire.

Le fait d’obtenir une lecture ‘zero’ apres avoir courtcircuite les cordons d’essai est aussi une preuve debon funcionement de l’instrument.

Pour vérifier l’état du fusible du circuit de continuité,laisser les cordons en court-circuit et placer lecommutateur de gamme sur la position ‘Ω’. Tourner lamanivelle du générateur. On doit obtenir une lecturetrès proche de zéro. En cas de lecture ohmiqueélevée, le fusible est coupé et doit être remplacé.

REMPLACEMENT DU FUSIBLELe fusible est placé dans un logement fixé entre lesbvornes de sortie de l’appareil. Pour remplacer unfusible, dévisser à l’aide d’un tournevis la partiecentrale du logement porte-fusible. Utiliser desfusibles ceramique 1 A (20 x 5 mm).

MESURE D’ISOLEMENTAprès avoir branché les cordons sur l’appareil et avoirréalisé les essais préliminaires indiqueés ci-dessus,placer le commutateur de gamme sur ‘MΩ’. Une fois lecircuit à tester isolé, brancher les cordons comme suit:

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( a ) Pour les essais d’isolement par rapport à la terre— Relier le cordon rouge à la terre ou au bâti de lastructure en essai, et le cordon noir à la partie ducircuit à mesurer.

( b ) Pour les essais entre fils— Relier un cordon à chacun des deux fils.

Tourner le manivelle à une vitesse comprise entre 160et 240 t.p.m. La valeur d’isolement sera lue surl’échelle ‘MΩ’ de l’indicateur. (Lors d’essais surcircuits capacitifs, l’aiguille de l’indicateur se déplaced’abord vers le zéro puis dévie graduellement jusqu’aprendre une valeur fixe quand la capacité est chargéeà la tension de sortie de l’appareil.)

Si plusieurs mesures successives fournissent unelecture ‘∞’, court-circuiter les extrémités des cordonsde mesure et tourner la manivelle de la génératrice.Une lecture ‘zéro’ indique que les cordons ne sont nidébranchés, ni coupés et que les mesuresd’isolement effectuées sont en fait correctes.

Les circuits capacitifs sont automatiquementdéchargés dans l’appareil quand on arrête de tournerla manivelle — L’aiguille se déplace au delà de laposition ‘∞’ puis reprend sa position de repos sur lamarque ‘∞’ quand le circuit est déchargé. Attendre letemps nécessaire pour que cette décharge se réaliseavant de débrancher les cordons d’essai. Le tempsde décharge est d’environ 8 secondes par microfarad.

ESSAIS DE CONTINUITEAprès avoir branché les cordons sur l’appareil, avoirvérifié leur état ainsi que celui du fusible, placer lecommutateur de gamme sur ‘Ω’ — Une fois le circuiten essai isolé, relier les cordons aux points à tester ettourner la manivelle à une vitesse comprise entre 160et 240 t.p.m. — La résistance est indiquées surl’échelle ‘Ω’ — Elle comprend la résistance descordons, qui doit être mesurée séparément (en court-circuitant leurs extrémités), cette valeur doit ensuiteêtre retranchée du résultat de la mesure.

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BETRIEBSANWEISUNG

A C H T U N G !1 . Vor der Isolierungs-oder Durchgangsprüfung m u ß

die zu prüfende Schaltung entladen und von derStromquelle getrennt werden.

2 . Nach der Prüfung kapazitiver Schaltungen sind dieTestkabel kurzzeitig angeschlossen zu lassen,damit sich die Schaltung entladen kann.

3 . In staubiger Umgebung eingesetzte Geräte sindregelmäßig zu warten und zu reinigen.

4 . Das Gerät niemals längere Zeit direkter Wärmedurch Sonneneinstrahlung aussetzen.

V O R P R Ü F U N G E NDas Testkab el auf gute nichtspröde Isolierung prüfen.Mit Kabelklemmen abgeschlossenes rotes undschwarzes Kabel verwenden Rote an (+), bzw.schwarze (–) Anschlußbuchse an das Gerätgehäuseanschließen. Die Kabel verdrillt bzw.zusammengedreht lassen, jedoch darauf achten, daßdie Klemmen nichts berühren. Schiebeschalter aufStellung ‘MΩ’ bringen. Die Generatorkurbel mit etwa160 Umdrehungen/MInute drehen und denMeßgerätezeiger beobachten. Er soll auf der Stellung‘∞’ (Unendlich) auf der Skale ruhen. Ist dies nicht derFall, können die Testkabel defekt sein, und sie sindgenauer auf eine Beschädigung zu untersuchen. DieKabel erforderlichenfalls ersetzen.

Die Kabelklemmen bzw. Enden verbinden und dieGeneratorkurbel erneut drehen. Das Meßgerät soll nunNull anzeigen. Liegt die Anzeige auf Unendlich oderbei einem hohen Widerstandswert, kann eineKabelunterbrechung vorliegen. Die Kabel genaueruntersuchen und gegebenenfalls auswechseln.

Bei Kurzgeschlossenen kabeln zeigt die Anzeige 0 anund man kann sich vergewissern ob das geratea r b e i t e t .

Um zu prüfen, ob die Sicherung in derDurchgangsschaltung in Ordnung ist, die Testkabelzusammengeschlossen lassen und denSchiebeschalter in die Stellung ‘Ω’ bringen. DieGeneratorkurbel erneut drehen: die Ablesung sollteNull (oder fast Null) ergeben. Wenn die Anzeige im ‘Ω’-Bereich über die volle Skale hinausgeht, ist dieSicherung defekt und zu erneuern.

AUSWECHSELN DER SICHERUNGDie Sicherung sitzt in einer Schraubhalterungzwischen den Ausgangs-Anschlußbuchsen. ZumAuswechseln der Sicherung den mittleren Teil desSicherungshalters mit einem Schraubenzieher lösen.Die alte Sicherung mit einer keramic 1 A, 20 x 5 mme r s e t z e n .

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PRÜFEN DER ISOLIERUNGNach Anschließen der Testkabel an das Gerät undAusführen der oben genannten Vorprüfungen denSchiebeschalter auf ‘MΩ’ stellen. Nachdem die zuprüfende Schaltung von der Stromquelle getrennt ist,die Tedstkabel wie folgt anschließen:( a ) Isolierungsprüfungen gegen Erde —

das rote Kabel auf Erde bzw. Rahmenmasse derjeweiligen Ausrüstung legen und das schwarzeKabel an den Teil der Schaltung anschließen ,dergetestet werden soll.

( b ) Isolierungsprüfungen zwischen Drähten —jeweils ein Kabel an die Drahtadern anschließen.

Die Generatorkurbel mit 160 bus 240 U/min drehen.Der Gerätzeiger zeigt den Wert desIsolationswiderstands auf der ‘MΩ’-Skale an. (BeimPrüfen einer kapazitiven Schaltung geht der Zeigerzunächst auf Null und steigt dann langsam auf denendgültigen Ruhewert, während die Kapazität auf dieAusgangsspannung des Prüfgeräts aufgeladen wird.)

Ergeben sich nacheinander mehrere Ablesungen von‘∞’, die beiden anderen Enden der Testkabelmiteinander verbinden und die Generatorkurbeldrehen. Dabei sollte man nun eine Nullablesungerhalten als Gegenprüfung dafür, daß die Kabel nichtgetrennt oder unter brochen sind undIsolationswiderstandsablesungen somit korrekt sind.

Kapazitive Schaltungen entladen automatisch durchdas Prüfgerät, wenn die Generatorkurbel nicht mehrgedreht wird. Der Gerätzeiger geht über die Stellung‘∞’ auf der Skale hinaus und kehrt dann zur normalenRuhestellung bei ‘∞’ zurück, sobald sich dieSchaltung entladen hat. Einige Augenblicke warten,damit die vollständige Entladung erfolgen kann, unddann die Testkabel abnehmen. Die Entladezeit (auf 0 V) beträgt ca. 8 Sekunden pro Mikrofarad.

D U R C H G A N G S P R Ü F U N GNach Durchführung der Vorprüfungen (wie bereitsbeschrieben) und Anschluß der Meßleitungen denSchiebeschalter auf die Stellung ‘Ω’ setzen. Die zuprüfende Schaltung muß von der Stromquelle getrenntsein. Die Testkabel an die zu messenden Punkteanschließen und die Generatorkurbel mit 160 bis 240 U/min drehen. Der Widerstand wird auf der ‘Ω’-Skale angezeigt. Dieser Widerstand enthält auch denWiderstandswert für die Testkabel, der (durchAusführen eines Tests mit kurzgeschlossenenMeßleitungen) separat zu messen ist; dieses Ergebniswird dann vom angezeigten Gesamtwert ab gezogen.

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INSTRUCCIONES DE USO

A D V E R T E N C I A1 . El circuito bajo prueba debe ser descargado y

aislado antes de efectuar las pruebas deaislamiento o continuidad.

2 . Cuando se han probado circuitos capacitivos,dejar transcurir un periodo de tiempo adecuadoantes de desconectar los cables, de modo que sedescargue el circuito, a través del instrumento.

3 . Los instrumentos usados en condicionespolvorientas, deben ser despiezados y limpiadosp e r i o d i c a m e n t e .

4 . Nos dejar los instrumentos expuestos a la luzdirecta del sol durante largos periodos de tiempo.

COMPROBACIONES PRELIMINARESInspeccionar las sondas de prueba para cerciorarsede que estén en buenas condiciones de aislamiento.

Conectar las sondas roja y negra rematadas en clipsen los enchufes terminales rojo (+) y negro (–)respectivamente situados en el lateral del instrumento.Pueden dejarse las sondas enrolladas o entrelazadasuna con la otra, pero ha de asegurarse que los clipsno hacen contacto con nada. Seleccionar elinterruptor deslizante en la posición “MΩ”. Girar lamanivela del generador en, aproximadamente, 160 r.p.m. y observar la aguja del indicador, la cualdeberá permanecer sobre la posición “∞” (infinito) de

la escala. Si esto no es asi, puede que esténaveriadas las sondas de prueba, y deberáninspeccionarse mas detenidamente por si estándañadas. Recambiarlas si es necesario.

Conectar los clips de las sondas nuevamente, girandola manivela del generador.

Al conectarse los cables y oztener que marca (zero)esto prueba que el instrumento funciona bein.

Para comprobar que está intacto el fusible incluido enel circuito de continuidad, dejar los conductores deprueba conectados y regular el interruptor deslizanteen la posición “Ω”. Girar nuevamente la manivela delgenerador. La lectura deberá reflejar cero (o muycerca del mismo).

Si la aguja indica una lectura más allá de la escalacompleta de la gamma “Ω”, el fusible se ha quemadoy deberá recambiarse.

RECAMBIO DEL FUSIBLEEl fusible es retenido en un alojamiento tipo roscablesituado entre los enchufes terminales de salida. Paracambiar un fusible, usar un destornillador con el fin deliberar la parte central del alojamiento que contiene elfusible. Recambiar el viejo con un fusible de cerámic1 A 20 x 5 mm.

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COMPROBACION DE AISLAMIENTODespués de conectar las sondas de prueba en elinstrumento y de efectuar las verificaciones indicadaspreviamente, seleccionar el interruptor deslizante en laposición “MΩ”. Con el circuito que ha decomprobarse aislado, conectar los conductores deprueba que sigue:( a ) Para las pruebas de aislamiento a tierra:

Conectar el conductor rojo a tierra o al bastidor delequipo y el conductor negro en la parte delcircuito que se desea comprobar.

( b ) Para las pruebas de aislamiento entre hilos:Conectar un conductor en cada uno de losnúcleos de los hilos.

Girar la manivela del generador entre 160 y 240 r.p.m.La aguja del instrumento indicará el valor deresistencia de aislamiento en la escala de “MΩ”. (Si seestá probando un circuito capacitivo, la aguja sedesviará inicialmente hacia el cero, para luego,gradualmente ascender hasta su valor final, a medidaque la capacitancia es cargarda hasta el voltaje desalida del probador.)

Si se obtienen varias lecturas sucesivas “∞”, conectarlos dos extremos de los cables de purebaconjuntamente y girar la manivela del generador.Deberá obtenerse una lectura cero, con lo cual secomprueba por partida doble que las sondas no están

desconectadas o rotas y que por consiguiente soncorrectas las lecturas de aislamiento. Los circuitoscapacitivos se descargan automaticamente a travésdel probado cuando se detiene el giro de la maniveladel generador. La aguja del medidor se desviará másallá de la posición “∞” en la escala para luegoretornar a su posición “∞” cuando se ha descargadoel circuito. Aguardar unos momentos para que estoocurra antes de desconectar las sondas de prueba. Eltiempo de descarga hasta 0 V es, aproximadamente,8 segundos por microfaradio.

COMPROBACION DE CONTINUIDADCon las sondas de prueba conectadas en elinstrumento, y una vez verificadas las sondas y elfusible, como se describe anteriormente, seleccionarel interruptor deslizante en la posición “Ω”.

Con el circuito que se está probando aislado,conectar las sondas de prueba entre los puntosapropiados y girar la manivela del generador entre160 y 240 r.p.m. La resistencia será indicada en laescala de “Ω”. Esta resistencia incluve a la de lassondas de prueba, la cual deberá medirseseparadamente (efectuando una prueba con los clipsunidos), y el resultado deberá restarse del total.

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SETTING-UP PROCEDURE

Notes on the basic setting-up procedure are given inthe table below. See ‘Repair and Warranty’ noteso p p o s i t e .

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S t e p Adjustment potentiometer Adjustment for Conditions for adjustment

1 . R 1 5 scale 10 MΩ mark (a) switched to ‘MΩ’(b) 10 MΩ (500 V rating) resistor across(b) t e r m i n a l s .

2 . R 1 6 scale 0 MΩ mark (a) switched to ‘MΩ’(b) short circuit across terminals.

3 . R 1 4 scale 1 MΩ mark (a) switched to ‘MΩ’(b) 1 MΩ (500 V rating) resistor across(b) t e r m i n a l s .

4 . R 1 7 scale 100 Ω mark (a) switch to ‘Ω’(b) 100 Ω resistor across terminals.

WM6

REPAIR AND WARRANTY

The instrument circuit contains static sensitive devices,and care must be taken in handling the printed circuitboard. If the protection of an instrument has beenimpaired it should not be used, and be sent for repair bysuitably trained and qualified personnel. The protection islikely to be impaired if, for example, the instrument showsvisible damage, fails to perform the intendedmeasurements, has been subjected to prolonged storageunder unfavourable conditions, or has been exposed tosevere transport stresses.

New Instruments are Guaranteed for 1 Year from theDate of Purchase by the User.

Note: Any unauthorized prior repair or adjustment willautomatically invalidate the Warranty.

Instrument Repair and Spare PartsFor service requirements for M E G G E R® I n s t r u m e n t sc o n t a c t : -

AVO INTERNATIONAL o r AVO INTERNATIONALArchcliffe Road Valley Forge Corporate CenterD o v e r 2621 Van Buren AvenueKent CT17 9EN Norristown, PA 19403E n g l a n d U . S . A .Tel: +44 (0)1304 502243 Tel: +1 (610) 676-8579Fax: +44 (0)1304 207342 Fax: +1 (676) 676-8625

or an approved repair company.

Approved Repair CompaniesA number of independent instrument repair companies have been approved for repair work on mostM E G G E R® instruments, using genuine M E G G E R® s p a r eparts. Consult the Appointed Distributor/Agent regardingspare parts, repair facilities and advice on the bestcourse of action to take.

Returning an Instrument for RepairIf returning an instrument to the manufacturer for repair, itshould be sent, freight pre-paid, to the appropriateaddress. A copy of the Invoice and of the packing noteshould be sent simultaneously by airmail to expediteclearance through Customs. A repair estimate showingfreight return and other charges will be submitted to thesender, if required, before work on the instrumentc o m m e n c e s .

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This instrument is manufactured in the United Kingdom.The company reserves the right to change the specification or design without prior notice.MEGGER is the registered Trade Mark of AVO INTERNATIONAL LIMITED.Copyright ©, AVO INTERNATIONAL LIMITED

Part No 6171-685 Edition 6 Printed in England 08GG

AVO INTERNATIONAL

Archcliffe Road POBox 9007 4271 Bronze Way MEGGER SARLDover Valley Forge Dallas 29 Allée de VillemombleKent, CT17 9EN. PA 19484-9007 TX 75237-1017 93340 Le RainceyEngland. U.S.A. U.S.A. Paris, FranceTel: +44 (0) 1304 502100 Tel: +1 (610) 676-8500 Tel: +1 (800) 723-2861 (U.S.A. only) Tel: +33 1 43.02.37.54Fax: +44 (0) 1304 207342 Fax: +1 (610) 676-8610 Tel: +1 (214) 330-3203 (International) Fax: +33 1 43.02.16.24

Fax: +1 (214) 337-3038