Summary of Contents for Polar Electro Toneohm 550A
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Polar Instruments Ltd. Garenne Park TONEOHM 550A Rue de la Cache St. Sampson OPERATOR Guernsey Channel Islands MANUAL GY2 4AF England Fax: 44 (0)1481 52476 MAN 149-9603...
TONEOHM 550A SHORTS LOCATOR OPERATOR MANUAL WARRANTY For a period of one year from its date of purchase new and undamaged from Polar Instruments Ltd, POLAR INSTRUMENTS LTD or its authorized distributors will, without charge, repair or replace at its option, this product if found to be defective in materials or workmanship, and if returned to POLAR INSTRUMENTS LTD or its authorized distributors transport prepaid.
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TONEOHM 550A OPERATOR MANUAL ELECTROMAGNETIC COMPATIBILITY European Community Directive Conformance Statement This product is in conformity with the protection requirements of EC Council Directive 89/336/EEC on the approximation of the laws of the Member States relating to electromagnetic compatibility. A declaration of conformity with the requirements of the Directive has been signed by...
SAFETY SAFETY WARNING The LIVE and NEUTRAL lines on this unit are BOTH fused. This unit contains no user-serviceable parts. When the unit is connected to its supply, the opening of covers or removal of panels is likely to expose dangerous voltages. To maintain operator safety, do not operate the unit unless the enclosure is complete and securely assembled.
Retain these instructions for later use. The TONEOHM 550A is designed for use indoors in an electrical workshop environment at a stable work station comprising a bench or similar work surface.
SAFETY CAUTIONS Electrical Isolation The TONEOHM 550A must not be connected to a powered board. Make sure that the item under test is isolated from all other sources of electrical power. External power could damage the tester. NOTE: The needle probes are manufactured from very hard steel to ensure that they stay sharp.
SPECIFICATIONS ACCESSORIES Standard Accessories Probe set ACC152 Operator manual MAN149 SYMBOLS CAUTION — To prevent damage to this product and to ensure its safe use observe the specifications given in this manual when connecting to terminals marked with this symbol.
Needle probes ..................... 2-3 2-4 Rear Panel controls and connectors ............... 2-3 SECTION 3 – INSTALLATION AND SET-UP ............. 3-1 PREPARATION FOR USE ..................3-1 3-1 Unpacking ....................... 3-1 3-2 Connecting the TONEOHM 550A to a power supply ........3-1 viii...
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CONTENTS SECTION 4 – OPERATION..................4-1 SYSTEM OPERATION..................... 4-1 4-1 Locating short circuits..................4-1 4-2 Using headphones ..................4-2 Short location example ..................4-3 SECTION 5 – SIMPLE MAINTENANCE AND CLEANING ......... 5-1 Cleaning ........................ 5-1 Technical Support ....................5-1 USER GUIDE (FRENCH) USER GUIDE (GERMAN) USER GUIDE (ITALIAN)
In many cases, short circuits may be pin-pointed to within 0.2 inches of actual fault location without the need to disconnect associated components or wiring. The sensitivity of the TONEOHM 550A allows it to be used for a wide variety of applications requiring low resistance measurements: •...
Using the TONEOHM 550A the technician can locate a short circuit between two tracks of a printed circuit board tracks by positioning the two Kelvin probes on the two tracks and listening for an audio tone.
TONEOHM 550A OPERATOR MANUAL 2-2 TONEOHM 550A stimulus features The low probe injection voltage of the TONEOHM 550A (maximum 60mV, typically 5mV) prevents possible damage to sensitive semiconductor components within the circuit under test. The TONEOHM 550A’s DC voltage injection avoids measurement errors which could result from stray currents flowing through capacitors connected in parallel with the circuits under test.
DESCRIPTION Probes Needle probes Place the Needle Probes across PCB tracks to locate short circuits between the tracks. 2-4 Rear Panel controls and connectors The rear panel accommodates the push button (push-on/push-off) ON/OFF mains power switch and the IEC mains inlet connector.
Note: If the instrument has been shipped or stored in a cold environment, allow the instrument to reach the temperature of its new location before applying power. 3-2 Connecting the TONEOHM 550A to a power supply Refer to the voltage label on the rear panel of the instrument and make sure that the marked rating is suitable for the local mains power supply.
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Check that the TONEOHM 550A mains switch (on the rear panel) is OFF. Plug the power cable into the receptacle on the rear panel of the TONEOHM 550A. Plug the other end into a wall outlet.
SECTION 4 – OPERATION SYSTEM OPERATION CAUTION: Disconnect power from the board under test before making measurements with the TONEOHM 550A Shorts Locator. 4-1 Locating short circuits • Switch the TONEOHM 550A on. • Rotate the VOLUME control fully clockwise.
A typical fault situation is shown diagramatically in Fig 4-1. 4-2 Using headphones The TONEOHM 550A incorporates the facility to output the audio tone to headphones if preferred. When the headphones are connected to this socket the internal speaker is switched off.
OPERATION Short location example In the example circuit in Fig 4-1, a short circuit exists between the output of U1 and the input of U2. Board power is disconnected, and the Needle Probes are placed at A and E. The resistance of the tracks via the short gives a reading and a tone. Moving the probe from A to B gives a lower reading and a higher tone.
TONEOHM 550A Service Manual to assist the service technician. Cleaning Clean the TONEOHM 550A with a cloth lightly moistened with water with a small amount of mild detergent. Alternatively, a cloth lightly moistened with alcohol (ethanol or methylated spirit) or isopropyl alcohol (IPA) may be used.
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ATTENZIONE: Scollegare l'alimentazione dalla scheda da testare prima di eseguire le misure con il Localizzatore di Corto Circuiti TONEOHM 550A. Introduzione Il Localizzatore di corto Circuiti TONEOHM 550A e' un milliometro di precisione comprendente: • Un generatore di toni Audio che varia la frequenza al variare della resistenza misurata •...
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TONEOHM 550A – GUIDA PER L'UTILIZZATORE Selezione della portata Utilizzare le portate ohm, 200mohm e 2 ohm per localizzare corto circuiti a bassa resistenza. Per localizzare i corto circuiti tra piste di maggiori dimensioni utilizzare il range ohm per disporre di maggiore sensibilita' e risoluzione.
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TONEOHM 550A – GUIDA PER L'UTILIZZATORE Esempio di localizzazione di un corto circuito Nel circuito di esempio indicato in figura 1, esiste un corto circuito tra l'uscita di U1 e l'ingresso di U2. L'alimentazione della scheda e' scollegata e i puntali a perforazione sono posizionati nei punti A ed E.
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Vergewissern Sie sich, ob die auf der Geräterückseite aufgedruckte Netzspannung mit der lokalen Netzversorgung übereinstimmt ! Überprüfen Sie, ob der Netzschalter des TONEOHM 550A (auf der Geräterückseite) in der Stellung OFF steht. Schließen Sie nun das Netzkabel in die zugehörige Buchse auf der Geräterückseite an.
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T OPERATOR MANUAL Lokalisieren von Kurzschlüssen • Schalten Sie den TONEOHM 550A ein • Drehen Sie den Lautstärkesteller VOLUME auf Rechtsanschlag • Wählen Sie die gewünschte Empfindlichkeit durch Drücken des zugehörigen Bereichsschalters - in den meisten Fällen ist den 200mΩ- Bereich der geeignete Bereich für die Kurzschlußsuche...
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INTRODUCTION Beispiel einer Kurzschlußlokalisierung In Abb. 1 existiert ein Schluß zwischen dem Ausgang von U1 und dem Eingang von U2. Die Versorgung der Platine wurde entfernt, und die Prüfspitzen wurden auf die Punkte A und E aufgebracht. Der geringe Widerstandswert zwischen den beiden Leiterbahnen bewirkt eine Anzeige am Display bzw.
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Check that the TONEOHM 550A mains switch (on the rear panel) is OFF. Plug the power cable into the receptacle on the rear panel of the TONEOHM 550A. Plug the other end into a wall outlet.
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TONEOHM 550A USER GUIDE Locating short circuits • Switch the TONEOHM 550A on. • Rotate the VOLUME control fully clockwise. • Select the desired sensitivity by pushing the associated range switch — in most cases the 200 mΩ range will be found appropriate for locating short circuits.
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TONEOHM 550A USER GUIDE Short location example In the example circuit in Fig 1, a short circuit exists between the output of U1 and the input of U2. Board power is disconnected, and the Needle Probes are placed at A and E.
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ATTENTION : Déconnecter l'alimentation de la carte sous test, avant d'effectuer des mesures de résistances Introduction Le localisateur de courts-circuits TONEOHM 550A est un milliohmètre de précision qui intègre : • Un signal sonore à tonalité variable en fonction de la résistance •...
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TONEOHM 550A – GUIDE UTILISATEUR Localisation des courts-circuits • Mettre le TONEOHM 550A en marche (sur ON). • Tourner le potentiomètre OFF-ON VOLUME à fond. • Sélectionner la gamme de sensibilité choisie - Dans la plupart des cas la gamme 200 mΩ est la plus appropriée pour les courts-circuits francs.
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TONEOHM 550A – GUIDE UTILISATEUR Exemple de localisation L'exemple de la figure 1 illustre le cas d'un court-circuit entre la sortie U1 et l'entrée de U2. L'alimentation de la carte est débranchée et les pointes de touche sont placées aux points A et E. La faible résistance entre les pistes via le court-circuit est visible sur l'afficheur et génère un signal sonore.
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