• Single- and three-phase transformer testing
• Fully automatic, fast, easy-to-use, robust, lightweight
• Battery powered
• Tests turns ratio, excitation current, and polarity
• Simple, one-button operation
• Quick-start guide on front panel

The Megger TTR20-1 is an automatic, hand-held, battery operated transformer turns ratio test set.

It is used to measure the turns ratio, excitation current and polarity of windings in single- and three-phase distribution and power transformers (tested phase by phase), potential and current transformers, and tapped transformers.

The unique design of the TTR20-1 allows the user to operate the test set while holding it in one hand. It effectively eliminates the user from having to kneel or bend down to operate the instrument and speeds up testing time. Realizing the extreme environments in which the TTR20-1 must operate, special attention has been paid to making it extra rugged, with a high impact, shock resistant case, yet incredibly lightweight at a mere 870 g (1.9 lbs). Its design makes this instrument well suited for use in a variety of harsh environments. The TTR20-1 is particularly suited for testing in substations, transformer-manufacturing environments, and meter shops. It features a high-contrast, backlit LCD screen which can be seen in bright or ambient light.

This unit measures a high turns ratio of 10,000:1 accurately with the lowest excitation voltage. The excellent repeatability of the TTR20-1 helps the users to determine the condition of transformers under test. It is designed for simple, one button operation with the measured results displayed directly on the easy to read LCD or printed to the optional printer.

The TTR20-1 needs no additional software and comes ready to use complete out of the box.

• Tests turns ratio, phase displacement, excitation current, vector group, winding resistance and polarity
• Fully automatic; fast; easy-to-use; handheld; robust; lightweight
• Battery powered with power-saving and shutdown function
• Alphanumeric keyboard
• RS232 for data transfer and printing
• Stores 200 test results and 100 user-defined transformer test settings

The TTR100-1 is a handheld, robust, lightweight and battery-operated instrument. This TTR will complement several existing Megger transformer test products and will offer functions, such as winding resistance and polarity. These functions, as well as the phase angle measurement function, can be switched off when not required.

With a turn ratio of 20,000:1, the TTR100-1 offers the highest turns ratio accuracy in the industry of 0.1%. The TTR100-1 features special software capabilities.

The TTR100-1 is used to perform final test and calibration of transformers in the manufacturing process, such as a QA or Test Department. Using the new TTR100-1 in this environment will improve the productivity of such QA testing, as well as efficiently collect and store large amounts of data, which can be uploaded to a PC spreadsheet, or database program.

• High Accuracy 0.01%
• Rugged Design for Field Use
• Versatile - Step Down & Step Up Ratio
• Designed to be used with large test clips or banana jack inputs
• Four-terminal Kelvin - no lead compensation required
• Universal standard for use with all ratiometers

The TRS1 is a unit designed to be used with ratio meters as a high accuracy reference ratio standard. This unique standard is able to provide ratios in both step down (traditional ratio test instruments) and step up (Biddle Hand Crank TTR) test modes. The standard is designed for use as a laboratory calibration standard, or as a portable check standard for field ratio and phase verification of any ratio instrument.

The TRS1 can be used with any single phase and three phase ratio meter. Combining three TRS1 units together, one is able to test a Wye-Wye configuration with three phase ratio meters. When testing three phase ratio meters with the TRS1, one uses the instrument’s single phase or three phase excitation for testing. This is meant as a time saving feature, or to validate TTRU3 phase ratio meter models.

• Lightweight, portable unit for field use
• Simple, semi-automatic operation
• Suitable for all oil breakdown testing to 60 kV
• Automatic 1 minute timer for easy withstand testing

The OTS60SX is a lightweight, semi-automatic, oil dielectric strength test set. The instrument is suitable for field use and is powered from a range of line voltages. The maximum 60 kV output allows tests to be performed on oil from a wide variety of electrical installations including transformers, circuit breakers and other equipment.

• Tests CTs mounted in transformers or switchgear
• Tests without changing leads

• With Model CTER-91 current transformers can be tested while mounted in transformers, oil circuit breakers breakers or switchgear - without moving bushings and CTs. Using the voltage-comparison method, Model CTER-91 provides a variable-voltage output up to 1000 volts and precision instrumentation for testing single and multi-ratio CTs.

• Guaranteed accuracy ±0.05% from -20°C to +50°C
• 3Ø test voltage - up to 250V
• 3Ø step up ratio (patent pending)
• Phase shifting & zig-zag transformers tested easily and accurately
• Smallest/lightest 3Ø test set on the market
• Fast 3Ø tests - less than 10 second

The NEW Megger TTRU3 transformer turns ratiometer uses a revolutionary design to perform a complete series of measurements on a transformer, including 3Ø step up turns ratio testing (patent pending). 3Ø voltage output offers numerous advantages to testing with today’s busy schedules. 

The TTRU3 is an important tool for determining the mechanical condition of transformers. All ratio tests are performed in one instrument, with only one 3Ø lead-set connection. The TTRU3 utilizes the latest 7 in. (180 mm) color touch display, as well as an optional printer so results are never lost. This is complimented with remote control which can be operated from a PC, as well as the ability to download results to a USB memory device.

•   Combines TTR and resistance testing in one box - faster, more efficient testing
•   55% smaller, 40% lighter than individual instruments
•   Only one set of leads required - lighter, smaller and less expensive
•   One test form - easier, faster to complete
•   Built-in demagnetisation

The Megger MWA300 and 330A Transformer Winding Analysers are here to offer you a faster, more efficient testing device through combining TTR and resistance testing in a single unit.

This advanced 3-phase transformer test system provides complete ratio, phase and winding resistance measurements with only one 3-phase lead-set connection. What’s more, it offers portability, a reduced set-up time and increased job safety.

Once connected, the MWA300 performs DC resistance measurements on all high- and low-side windings without reconnection. It has an 8-terminal/6-winding resistance measurement capability and doesn’t need any inter-connected boxes, allowing you to test all 6 windings without having to disconnect and reconnect leads.

The MWA300 series saves you even more time by using a single software platform, PowerDB, which means you only need one set-up and one easy-to-use test form.

The MWA300 series can be used effectively test power transformers, distribution transformers, CTs and VTs, and motors and generators.

The following tests are easily performed with a single instrument, the MWA300 series, and a single 3-phase lead set connection:

•   3-phase turns ratio
•   3-phase winding resistance
•   OLTC continuity (make-before-break)
•   3 phase core demagnetization
•   Magnetic balance / flux distribution
•   Excitation current
•   Polarity and phase angle deviation
•   Auto vector detection
•   Heat-run test

The MWA330A comes equipped with a built-in computer that has a 305 mm (12 in) colour display and touch-screen interface. The computer is designed to control the unit and it can store up to 100, 000 data sets.

• Automated 8-terminal/6-winding measurement capability
• Simultaneous winding magnetization
• Tests operation of on-load tap-changers
• Built-in auto-demagnetization feature
• Automatic discharge
• Power DB software (MTO330)

The MTO 300 series delivers full eight-terminal/six-winding resistance measurement capability. It is designed to save time for the user by testing all normal 6 windings without having to disconnect and reconnect leads during testing.

The MTO3xx series also shares the Megger TTR300 series lead set. Users who test both turns ratio and winding resistance can save time and money since only one lead set is needed to connect to the transformer.

• Capable of testing transformers up to 1000 MVA
• DC test current up to 50 A maximum
• Integrated demagnetisation feature
• Computer control and internal data storage
• Validates proper operation of on-load tap-changers
• Protected against accidental current lead disconnection (through potential leads)

The MTO250 Transformer ohmmeter is a line-operated, field-portable instrument designed specifically to measure the resistance of all types of magnetic windings safely and accurately. It tests transformers, shunt reactors, rotating machine windings and performs low resistance measurements on connections, contacts and control circuits.

The dual set of potential inputs enables the resistance measurement of either two primary, two secondary windings, or of a primary plus a secondary winding simultaneously. This dual reading, dual injection characteristic, is a highly efficient method of completing tests in a timely manner.

• Entry level transformer ohmmeter
• 2 channels with max 6 A current output
• ±0.25% measurement accuracy
• 48 V test voltage for fast saturation of transformers
• Multimeter type operation, intuitive and fast
• Safety through automatic, passive discharge circuitry
• True portability – compact size and low weight

The MTO106 transformer ohmmeter is an easy-to-use, line-operated instrument specifically designed for safe and accurate field measurement of winding resistance in smaller transmission and distribution transformers. It has dual channels with a measurement range and accuracy suited to provide accurate information about the vast majority of power transformers, reactors and instrument transformers. The test current can be manually set in five different ranges to fit transformers of various sizes.

The instrument is exceedingly simple to use, which minimises the need to train users. It has a single selector switch for test current and a single button to activate the test cycle. The instrument is also supplied with test leads fitted with Kelvin clamps that allow for a single, one-time connection to the unit under test. The test leads are 10 m (33 ft) in length to allow for easy testing of pole mounted transformers.

The compact and lightweight instrument is housed in a rugged plastic case for true portability. When closed, the case is rated IP67, which means your instrument will always arrive safely to the testing location even in the harshest conditions.

Users are protected by an automatic discharge function that de-energises the transformer winding at the end of every test. The discharge function is passive and thus also functions if there is an inadvertent loss of power or if the test or mains leads are accidentally pulled.

• Measures the short circuit impedance of transformers
• Useful in detecting and diagnosing winding deformation
• Capable of performing measurements in single- or three-phase transformers
• Optional capacitor bank testing

The Megger Leakage Reactance Tester MLR10 is used to measure leakage reactance and other associated parameters in high voltage power transformers.

The unit is offered as a stand-alone unit, which requires the use of an external PC, running Megger’s proprietary MLR10 free-of-charge software.

• Winding resistance measurement
• Dynamic resistance measurement (DRM)
• Switch sequence timing
• Transition resistor measurement

LTC135 is an accessory for circuit breaker analysers to test load tap changers where it delivers test currents for the measurements.

The load tap changer is the only moving part connected to the transformer windings. Taking a transformer off the system to investigate an internal problem with a tap changer is an expensive exercise; therefore it is in every utility’s interest to carry out condition assessments of their tap changers to help detect developing faults at an early stage.

LTC135 is designed to be used together with the following Megger instruments:

EGIL TM1600/MA61 TM1700 series TM1800

Together with the circuit-breaker analyzer (CBA) it becomes a a test setup for performing dynamic measurements on load tap changers.

The unit can also be used for winding resistance measurements and other applications where a constant DC current test signal is requested. It is a power supply designed for DC current testing of inductive loads with provisions for discharging the transformer winding when the test is finalised.

• Expert Technical Assistance
• Annual On-Site Training
• Engineering Consultation & Results Analysis
• 24/7 Telephone Support
• Maximize Uptime
• Expedited Repair Services
• Loaner Units & Standard Accessories
• Keep Pace with Industry Practices & Trends

The Megger technical support team will assist and guide clients in configuring the test equipment, performing tests, and saving the results for future trending and record keeping. Assistance includes troubleshooting and ensuring proper operation of the equipment. Clients will have access to expert interpretation of IEEE/ANSI standards when testing a unique equipment with special applications. A hotline number will be provided to Priority Access Program clients to call 365 days a year.

• Robust oil chamber lid, fully opening for easy access
• Robust and protective control panel lid
• Lightweight portable unit for field use
• Simple, semi-automatic operation
• Suitable for all oil breakdown testing to 60 kV
• Automatic 1 minute timer for easy withstand testing
• 1ms HV switch off time eliminates damage to the oil samples

The OTS60SX is a lightweight, semi-automatic, oil dielectric strength test set. The instrument is suitable for field use and is powered from a range of line voltages. The maximum 60 kV output allows tests to be performed on oil from a wide variety of electrical installations including transformers, circuit breakers and other equipment.

• Separate high voltage amplifier enables capacitance and dissipation factor measurements at 2 kV test voltage
• True and proven DFR/FDS technology for highest performance
• Large frequency range, DC to 1 kHz
• Compact design, weight < 5 kg

VAX020 expands the IDAX300 test voltage range from 200 V to 2 kV. This improves the capability to perform accurate measurements in extreme high interference environments e.g. HVDC substations.

Besides 50/60 Hz capacitance and dissipation factor (power factor) measurements, the application gives valuable information about the general condition of any high voltage insulation by measuring its dielectric response. The technique is also capable of assessing the moisture content in oil/paper insulation systems.

• Expands the range of capacitance and dissipation factor (power factor) test sets
• Capable of tuning capacitances up to 1µF at 10 kV
• Hand-crank tuning wheel
• Core gap gauge that displays position of inductor core
• Large wheels and handles for easy transport

The resonating inductor is an accessory for use with the semi-automatic 12 kV extended-range capacitance and dissipation factor test set, or the automated insulation power factor test set (DELTA series).

The resonating inductor is used to expand the capacitance range of these test sets and cannot be used with the standard 12 kV capacitance and dissipation factor test set.

The resonating inductor is connected in parallel with the internal power supply of the test set. A manual tuning wheel on the resonating inductor varies the inductance to tune the parallel circuit for minimum load current.

When used with the semi-automatic 12 kV extended-range capacitance and dissipation factor test set, or DELTA series, the resonating inductor will extend the short-time rating of the power supply from 200 mA to 4 A. This capacity is suitable for testing capacitance loads of up to 1 µF at 10 kV.

• Routine and advanced diagnostic tests
• Centralized control and reporting
• Two sets of cables (HV and LV) are shared among different instruments
• Automated test circuit arrangement and switching process
• Safe operation and user guidance through the tests
• Easy extraction of mounted instruments for standalone use

Increased transformer test efficiency.

To stream-line your on-site assessment of power transformer condition the Megger transformer test van is equipped with a selection of instruments. It arrives on site ready for action to start testing, to rapidly yield and store results, and it even simplifies packing up for you.

The dedicated transformer test van helps you perform a range of routine electrical tests and advanced diagnostic techniques to international standards. Commissioning testing confirms that the system conforms to the design parameters, while the on-going maintenance tests confirm that no changes are occurring, and confirm the safe uninterrupted operation of the power transformer and substation.