Master Sales Consultants of Test and Measurement Instruments and Industrial Supplies

Transformer testers

Transformer testing

Transformer testing Transformers are very reliable devices and can provide service for a long time if maintained and serviced regularly. They are also the single most costly item in any substation. To protect against failures that can result in costly repairs and long periods of downtime, trust your transformer to the accurate and reliable test equipment from Megger. The best insurance against transformer failure is to ensure that they are properly installed and maintained. The complete line of Megger equipment make testing easy and accurate.

Megger is the leader in ratiometer sales worldwide.

If you are looking for the most meaningful analysis available, but demand easy, quick and safe testing, look for Megger transformer testing products.

Documents (all documents are in PDF format and will open in a new window)
Click here for Application Guides, Articles and FAQs



12 kV Power Factor (Tan ð) Tester


Circuit Image

• Power factor test set
• Automatic and manual operation
• Accurate and repeatable measurement results with high noise suppression
• Lightweight, rugged two-piece design
• New built-in intelligent temperature correction (patent pending)
• New automatic voltage dependence detection (patent pending)


DELTA4000 series is a fully automatic 12 kV insulation power factor / dissipation factor (tan delta) test set designed for condition assessment of electrical insulation in high voltage apparatus such as transformers, bushings, circuit breakers, cables, lightning arresters, and rotating machinery.

Two configurations make up the Series:

DELTA4110 with external computer (not included) consists of the DELTA4100 control unit and DELTA4010 high-voltage unit

DELTA4310 comes with onboard computer and consists of DELTA4300 control unit and DELTA4010 high-voltage unit



Relay and Current Transformer Tester

Circuit Image

• Industry leading test duration using patented simultaneous multi-tap measurements reduces testing time by 20% on multi-tap CTs
• Increased measurement accuracy to support metering class CT testing
• Smallest and lightest 2 kV secondary voltage injection unit on the market
• Integrated single phase relay test system
• General purpose substation secondary circuit testing with 300 V & 60 A generators
• Grouped testing: demagnetization, knee points, ratios, saturation curves, and more
• Measure all ratios and saturation curves on multi-tap CTs with one lead connection
• Built-in insulation resistance testing

The Megger MRCT is a light weight, robust, portable unit used to perform demagnetization, ratio, saturation, winding resistance, polarity, phase deviation, and insulation tests on current transformers. The MRCT automatically calculates ratio errors, saturation curves, and knee points. The MRCT provides a microprocessor-controlled variable voltage and current output and precision instrumentation for automatically testing single and multi ratio CTs, reducing testing time and increasing productivity. The MRCT will directly connect to multi ratio CTs and perform all tests – saturation, ratio and polarity, winding resistance and insulation – on all taps with the push of a button and without changing leads.

The MRCT can be controlled via Megger’s Smart Touch View Interface (STVI) controller. The STVI controller is a full color, high resolution, LCD touch screen which allows the user to perform manual and automatic testing quickly and easily using the manual test screen, as well as using pre-constructed test routines. The large color display permits the user to easily read all pertinent data while the test is being performed and provides the ability to view the current transformer’s saturation curve. The unit can also be configured to come without a Megger STVI and can be controlled via a laptop with Megger’s PowerDB software.

Current transformers can be tested in their equipment configuration, such as being mounted in transformers, oil circuit breakers or switchgear. It is necessary for the equipment to be completely isolated from the electrical system prior to testing.


TTR300 Series

Three-Phase Transformer Turns Ratio Tester

Circuit Image

• Stand-alone or remote-control operation
• Accurately measures ratio, phase deviation and exciting current
• Field upgradeable without compromise to calibration
• Built-in capability for storing and downloading test results in an XML format, via RS-232, Ethernet or USB ports (depending on model)
• Highest ratio measurement (45,000:1); highest accuracy (0.1%)

The TTR300 Series of three-phase transformer turns ratio test sets are designed to measure the turns ratio of power, instrument, and distribution transformers in a substation or manufacturing environment. The instruments are ideal for use by power transformer manufacturers. Their unique testing procedures and storage capability allows an operator to set up and test difficult three-phase transformers in a fraction of the time than it used to take with other TTRs.

The TTR300 Series also measure the phase deviation of the transformer primary versus secondary. This quickly indicates problems such as partial shorted turns and core faults. This is also useful in verifying phase errors in all types of PTs and CTs.

Each unit comes equipped with a remote-control switch for single person testing. This allows the operator to test transformers with LTCs very quickly.

The Series consists of three instruments:

The TTR300 is designed to be completely remote controlled via a PC running PowerDB LITE (included) or PowerDB (full version) PC software applications. The TTR300 is field upgradeable to the TTR310, TTR320 or TTR330.

The TTR310 has the ability to store test results, upload results to a PC (via RS232 serial port), and/or print them in the field via optional thermal paper printer, without the use of an external computer. Please note: The TTR310 is a direct replacement for the three-phase TTR, C/N 550503

The TTR330 offers a new user interface which allows the operator to interact with the PowerDB ONBOARD software system via full QWERTY and navigation keypads as displayed on an 8.4” VGA bright-color screen. An advanced feature of the TTR330 allows the user to customize test forms via optional full-version PowerDB.