Winding Resistance
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Single-Phase Transformer Winding Resistance Meters
RMO-TW Series
RMO-TW series is perfect for winding resistance measurements of inductive objects. It is ideal for testing transformer windings (power transformers, distribution, autotransformers) and for on-load tap changer verification. In addition, any RMO-TW transformer ohmmeter & tap changer analyzer can also perform transformer demagnetization.The series contains 4 models, with maximal test currents from 10 A (RMO10TW) to 50 A (RMO50TW). They are fitted in a portable and lightweight metal housing.All transformer ohmmeters from RMO-TW series generate a true DC ripple-free current with automatically regulated measurement and discharging circuit. The injection of current and discharge of energy from the test object are automatically regulated.Three independent channels enable testing of three windings in series. Consequently, this enables measurements of winding resistance in every tap position of an on-load tap changer without discharging between the tests.DV-Win software enables control and observation of the test process, as well as saving and analyzing the results on a PC. It provides a test report, arranged in a selectable form as an Excel spreadsheet, PDF, Word, or ASCII format. Additionally, DV-Win measures and calculates the OLTC transition time, the ripple and the winding resistance for each tap changing operation. The software can also perform the calculations necessary for the “Heat Run” test. Finally, a user can export all results in the form of a report.
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Winding Resistance Tester with Demagnetisation Circuit
WRT-10D
The WRT-10D is a high performance winding resistance tester designed for power transformer and large motor applications. It is equipped with a bright LCD display, a rugged high quality cable set, a built-in printer, a full QWERTY keypad and a demagnetisation circuit.
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Switch Module
STCS
The external module STCS allows performing automatically the following PT tests: ratio per tap; winding resistance; OLTC dynamic test. The connection to the transformer under test, to STS and to the measurement taps is performed just once; then, all transformer tests are performed without interruptions.
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Three-Phase Transformer Demagnetizer
DEM60C
After a DC current test, such as winding resistance measurement, the magnetic core of a power or instrument transformer may be magnetized (remnant magnetism). It can cause various problems such as wrong diagnostics, inaccurate measurements on a transformer, inrush current at the start-up of a power transformer, or incorrect operation of protective relays due to magnetized CT cores. The best way to eliminate this source of potential problems is to use demagnetizer on the power or instrument transformer.The DEM60C is a fully automatic test instrument which performs three-phase transformer demagnetization. Transformer magnetic core demagnetization requires the application of AC current with magnitude decreasing to zero. DEM60C provides this AC current by internally changing the polarity of a controlled DC current. During the demagnetization process, the instrument supplies the current at decreasing magnitude for each step, following a proprietary algorithm. It can demagnetize single-phase and three-phase power transformers.The instrument can be connected to all three phases of a power transformer to be demagnetized, on either the primary or the secondary side. If a user selects specific vector diagrams for different types of transformers, DEM60C will run a specific demagnetization procedure for each transformer type (i.e., single phase, delta, wye/star, zig-zag.) without switching the test leads.DEM60C enables safe and efficient power transformer demagnetization. The instrument automatically regulates the injection of current and discharging energy from the inductance. During and after the operation, an intrinsically safe discharge circuit with an indicator rapidly dissipates the stored magnetic energy. The discharging circuit is independent of the power supply, which improves its reliability in case of loss of power.Test currents of up to 60 A DC enable efficient demagnetization of even the largest power transformers. Using a DV Win software, it is possible to control DEM60C externally.
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Current Transformer Tester
CTT
The CTT is designed to test the current transformer ratio, Phase shift, Polarity, Excitation, Saturation, Winding resistance and Insulation resistance using the voltage method in compliance with ANSI/IEEE C57.13.1 and IEC 60044-1 standards, where voltage is applied to the secondary X terminals of the current transformer.
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Electrical Measurements Test
The tests are performed to measure and collect data from electrical and electronic parts using various measurement methods including, but not limited, to the following: capacitance, resistance, winding resistance, insulation resistance, magnetic permeability, power input, and quality factor Q.
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Handheld Turns Ratio & Winding Resistance Tester
TWR-H Series
Handheld TWR-H device is DV Power single-phase instrument designed for measuring transformer winding resistance and turns ratio.The instrument has two output DC sources for measuring transformer winding resistance. The first DC source can output up to 2 A DC and is used for injecting current to the transformer’s high voltage winding. The second DC source can output up to 10 A DC and is used for testing the transformer’s low voltage winding. This is especially useful when measuring winding resistance of distribution transformers. These transformers have large turns ratio and therefore a big difference between resistances of high voltage and low voltage windings. Upon the winding resistance test, it is also possible to demagnetize the transformer core. The demagnetization process is completely automatic and safe.Together with the turns ratio, the instrument also measures excitation current and phase shift. This enables detecting transformer core or winding turns failures which cannot be spotted by measuring turns ratio only. The instrument can output test voltage up to 40 V AC for this test, but it can also output a very low test voltage of 1 V AC which is necessary for turns ratio verification of the majority of current transformers.TWR-H is powered by an internal Li-Ion battery. Up to 100 tests can be performed with a fully charged battery.
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Transformer Winding Resistance Meter
10A
*10A DC continuous current in 4 ranges of 0.01A, 0.1A, 1A and 10A.*4 ½ digit display for higher resolution.*Dual channel measurement.*Suitable for operation in energized switchyard conditions.*Specialized protection circuits for suppression of inductive voltage kickback.*SMPS based - lightweight and portable.
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Portable Winding Resistance Tester
1. Handheld winding resistance meter2. Conversion function for standard temperature resistance.3. 500 test data can be saved and download by flash disk.4. Temperature testing function.
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Winding Resistance Meters
The NMC 'TDR' is a high precision, new generation, light weight large output current and micro-processor controlled tester. This replaces old DC wheat stone bridge and double arm bridge for measurement of DC resistance. 'TDR' adopts new advanced test current power supply technology, four terminal measurement, digital display of resistance value and test current. 'TDR' is powered by 220V AC mains single phase supply. The measurements are accurate as the test current is highly stable. High automation is achieved with automatic discharge warning.
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Current Transformer Analyzer
CT Analyzer
Current transformer testing in a multifunctional instrument performing excitation, ratio, polarity and winding resistance tests on current transformers as well as burden impedance measurement.
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Transformer Winding Resistance Meters
TWA Standard Series
The TWA standard series instruments are designed to measure the resistance of six coils and simultaneously analyze the three-phase tap changer on load of the primary and secondary transformer coils (provided by model TWA40). This is done in a single cable configuration, with test currents up to 40A. Each transformer configuration has a special measurement algorithm that is optimized for rapid stabilization of test results. The TWA instruments generate a true DC current without ripple. Both current injection and magnetic circuit energy discharge are automatically regulated.
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Microohmmeter
MMR-6500
The MMR-6500 digital meter is designed for measuring low resistances with a stabilised current of up to 100 A. The use of test clamps enables the safe measurement of breakers (high-, medium- and lowvoltage), isolators and other components earthed on both sides. The MMR-6500 series meters are equipped with a unique module in their class that measures inductive components which have a current of up to 10 A, enabling the winding resistance of motors, transformers and other inductive components to be measured. Another useful function is the temperature measurement and the automatic compensation of results with relation to the measured temperature or temperature set by the user. The system is completed with a recorder function. Special measuring algorithms and additional functions allow an appropriate measuring method to be chosen depending on the measured component and measurement conditions, thus, widening the application areas of the meter. The state-of-the-art user interface, various communication interfaces, wireless communication and communication with the computer, printer, 2D code reader are integrals features which enable full, comfortable and intuitive management of not only measurements and their results but also ID data of measured components.
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DIGITAL TURNS TESTER AND DIGITAL LCRTZ METER
TURNS-LCRTZ
Digital TURNS TESTER with LCR for Counting / Measuring Number of Turns for Toroidal Coils , Current Sensor , Current Transformer , Round Core Coils. Can measure, Turns along with Winding Polarity , DC Resistance , Inductance (L), Capacitance (C), DC Resistance, Rac, Q, D, ESR and Tan.Toroidal Turns Platforms :TTPT100 : 5 T - 1000 T , TTPT1000 : 500T-10000 T The Platform has 2 connections for the coil and 2 for the probe wire. Measurement principle is based on dynamic comparison of the voltage across one turn and the coil. You will be able to get the polarity or winding indication with respect to the one turn reference.Accuracy : + 0.2% + 0.5T for high and medium permeability cores at suitable test frequency. Internal Diameter must be able to pass a wire as thin as 0.2 mm. External Diameter as high as 200 mm.Test Frequency Selectable in Step : 50 Hz, 100 Hz , 500 Hz, 1 KHz, 5 KHz, 10 KHz. Test Voltage adjustable : 100mV to 1V in steps of 50mV.
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Mini Automatic Transformer Observation System
mini-ATOS
The mini-ATOS, is a professional multifunctional power transformer and substation diagnostic system. This compact and intelligent instrument can perform many routine and advanced tests such as Winding Resistance (WR), Dynamic Resistance Measurement (DRM), Turns Ratio (TR), Frequency Response of Stray Losses (FRSL), Magnetic Balance, and other diagnostic parameters. With the built-in fully automatic multiplexer, only a one-time connection is required for nearly all functions, which saves a considerable amount of time. The portable, rugged case is perfect for use anywhere onsite or in a laboratory. It is specially designed for fast and easy measurements with the well-known high precision and quality of all Raytech instruments.
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Primary Current Injection Test Set
T 2000
T 2000 is a portable current transformer test set which allows to perform many different measurements such as saturation, ratio and polarity tests and CT winding resistance test. Substation maintenance and commissioning test equipment, T 2000 is extremely appreciated by electrical engineers for its high accuracy and portability.
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Current Transformer Testers
Vanguard Instruments Company, Inc.
Performs CT excitation, current-ratio, polarity, and phase angle testsMeasures insulation resistance and winding resistance of the CT seconday windingsMeasures the CT's secondary burdenTest record header information including company, substation name, circuit ID, manufacturer, CT serial number, operator name, and test record-commentsBuilt-in 4.5-inch wide thermal printerPlot Multiple Saturation CurvesStores up to 128 CT test plans and 140 test records internallyUSB, Bluetooth, and USB Flash drive interface
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Relaying Current Transformer Analyser
*Measures Ratio, Excitation Characteristics, Polarity, Winding Resistance, Remanance, and Insulation Resistance of secondary winding. * Determines Composite Error. * Used to test un-mounted CTs or CTs that are mounted but isolated inside the power system equipment. * Conducts a whole series of tests automatically, thus speeding up the time to commission CTs and relaying systems. * Battery powered test set - light weight & fully portable. * Provides a graphical presentation of the CT excitation characteristics. * Determines the IEC 10/50 knee point and the point of maximum permeability, ANSI 45 degree Slope Point. * Detects shorted turns or insulation problems within the test CT, thus avoiding commissioning of faulty equipment.
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STDETransformer Demagnetizer
STDE
This option allows neutralizing the residual magnetization of the power transformer core after the winding resistance test. The principle of the option is to apply a constant current of alternate polarities to the transformer winding, as per the IEEE 0062 1995 standard.
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Transformer DC Winding Resistance Tester
HTZZ-10A / 235
Wuhan Huatian Electric Power Automation Co., Ltd.
Measurement transformer around the group and large power inductor dc resistance ideal equipment.
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Transformer DC Winding Resistance Tester
HTZZ-40A / 245
Wuhan Huatian Electric Power Automation Co., Ltd.
Measurement transformer around the group and large power inductor dc resistance ideal equipment.
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Multiplexer For Transformer Testing
MUX-R
Raytech Multiplexer MUX R is designed to drastically reduce cabling time and increase test performance. It is made to be used with Raytech Winding Resistance and Turns Ratio Meters. Any MUX R configuration can be easily controlled by a Winding Resistance Meter touch panel or by remote.
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Winding Resistance Meter 50Amps, 3 Channels Rack
WR50-13R
Raytech Digital Winding Resistance meter WR50-13R is the enhanced version winding resistance system with a most advanced demagnetizing circuit as a rack version. It is designed for high degree of accuracy for the measurement of very low resistance of any inductive loads.
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Winding Resistance Meter 100Amps, 2 Channels
WR100-12R
Raytech Digital Winding Resistance meter WR100-12R is the enhanced version winding resistance system with a most advanced demagnetizing circuit as a rack version. It is designed for high degree of accuracy for the measurement of very low resistance of any inductive loads.
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Transformer Heat Run Tester
1. Suitable for all transformers below 240MVA heat run test and winding resistance testing.2. Printing heat run data automatically.3. With double power supply, can test high voltage side and low voltage side simultaneously and test any operation respectively.4. With anti breakage protection function of inductive test items.
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AC Motor Tester
AIP892X series
Qingdao AIP Intelligent Instruments Co., Ltd
This product is suitable for electrical performance testing of all types of motors, such as home appliance motors (washing machines, air conditioners, fans, etc.), pump motors, stepper motors, etc. One-stop testing completes all set items, stable, fast, efficient and accurate, widely used by domestic and foreign enterprises.This AC motor tester test items: AC Hi-pot, insulation resistance, surge, DC winding resistance, no-load characteristics, low voltage start, locked rotor, rotation, PG characteristics.
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Tap Changer Analyzers & Winding Ohmmeters
Winding resistance test of inductive test objects, such as power transformers, is one of the most effective non-intrusive ways of checking its condition. Due to their advanced design, DV Power winding resistance meters provide high test currents (up to 100 A DC) and high accuracy (up to 0.1%) within light and portable test instruments. In addition to winding resistance measurement, it is also possible to perform simple, quick and reliable transformer on-load tap changer condition assessment by recording the test current during tap changer operation, also known as DVtest. Because of that, problems with a tap changer connection, contacts, and switching procedure can be detected.DV Power winding ohmmeters consist of single-phase RMO-T and three-phase TWA series. Models from the TWA series are designed for six-winding resistance measurement of power and distribution transformers, with only one single-step cable setup. As a result of reducing the total test time, it enables significant saving of time and money.Typical application areas of these instruments are high-voltage substations and industrial environments. They are intended to measure the resistance of:Transformer windingsOn-load tap changersGeneratorsElectrical motorsHigh-current bus bar jointsCable splicesWelding joints
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Transformer Ratio Meters
Handheld Turns Ratio & Winding Resistance Tester TWR-H
TWR-H is a handheld, battery operated, fully automatic test set specially designed for turns ratio, phase shift, excitation current and winding resistance measurements of transformers. It can also perform demagnetization of these transformers. Transformer turns ratio is determined by applying AC voltage across high voltage winding, accurately measuring AC voltage across the corresponding unloaded transformer winding, and then displaying the ratio of these voltages. User can enter a transformer’s nameplate voltages, so that turns ratio deviation can be calculated. This feature eliminates any error otherwise caused by an operator’s manual calculation. TWR-H compares measured turns ratio with the nameplate ratio and prints out the % of error for each test. Transformer winding resistance is determined by injecting DC current through a winding, accurately measuring DC voltage across the winding, and then calculating resistance as the ratio of voltage and current. The device generates true DC ripple-free currents. Both the injection of the current and the discharge of energy from transformer magnetic circuit are automatically regulated.
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Transformer Testing Instrument
The Motwane Manufacturing Company
Transformers are a vital link in the electrical distribution system. Accurate and timely transformer maintenance can prevent breakdowns by detecting potential causes, and eliminating them before danger strikes. In addition, regular maintenance ensures multiple years of trouble-free operation. Motwane offers a wide range of transformer maintenance products, such as the transformer turn ratio tester, winding resistance tester, automatic oil BDV tester, and oil tan delta resistivity tester.
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Microohmmeter
MMR-6700
The MMR-6700 digital meter is designed for measuring low resistances with a stabilised current of up to 200 A. The use of test clamps enables the safe measurement of breakers (high-, medium- and lowvoltage), isolators and other components earthed on both sides. The MMR-6700 series meters are equipped with a unique module in their class that measures inductive components which have a current of up to 10 A, enabling the winding resistance of motors, transformers and other inductive components to be measured. Another useful function is the temperature measurement and the automatic compensation of results with relation to the measured temperature or temperature set by the user. The system is completed with a recorder function. Special measuring algorithms and additional functions allow an appropriate measuring method to be chosen depending on the measured component and measurement conditions, thus, widening the application areas of the meter. The state-of-the-art user interface, various communication interfaces, wireless communication and communication with the computer, printer, 2D code reader are integrals features which enable full, comfortable and intuitive management of not only measurements and their results but also ID data of measured components.




























