The Megger MWA3 Series Transformer Winding Analyzer

The Megger MWA3 Series Transformer Winding Analyzer is designed to perform transformer  ratio and winding resistance testing in one box quickly and efficiently. It is an advanced three-phase portable transformer test system that reduces set-up time, increases job-site safety and delivers improved productivity versus individual instrument testing.

The unit’s light weight (15kg/32 lbs.) and small size (280 x 280 x 460 mm/11 x 11 x 18 in.) makes it 40% lighter to carry and offers 55% more space in vehicles than other equipment on the market today. The ease and convenience of using the same set of test leads eliminates the need for frequent ladder trips and mistakes with lead connections from one lead set to another; one set of leads equals one ladder climb.

The MWA3 Series provides complete ratio, phase and winding resistance measurements for a three-phase transformer. All ratio and winding resistance tests are performed in one instrument with one three-phase lead-set connection. Testing complex three-phase transformers becomes easier with the MWA3 Series, as operator uses one setup, one connection and one common test form for a consistent, easy-to-learn test method.

The following tests are easily performed with the MWA3 Series, all with one instrument and one three-phase lead-set connection: 3-phase turns ratio, 3-phase winding resistance, auto vector detection, heat-run test, OLTC/continuity (make-before-break), core demagnetization, magnetic balance/flux distribution, excitation current, polarity, and phase angle deviation.

There are two interface options available. The externally-controlled model MWA300 is a “black box” style package that is remotely controlled by PowerDB software running on an external PC (not provided). The MWA330A model (available August 2017) features a built-in 12-in./300-mm industrial touch-screen computer.

PowerDB software provides the unit with a common user interface to minimize operator training and delivers a seamless interface to the computer application. PowerDB Lite software is included with the MWA3 Series.

Typical end users of the MWA3 Series include power utilities, electrical testing companies and field commissioning, service and maintenance personnel. For more information, please visit