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  • State-of-the-art, high voltage DFR instrument tailored for field testing of power transformers, bushings, current transformers, voltage transformers, cables and more.
  • The IDAX322 instrument and its accessories are designed for the most demanding field conditions
  • 2 kV peak and 50 mA capacity – ideal for low capacitance objects such as bushings and instrument transformers
  • Best hardware and specifications for the most accurate results
  • Easy to use software with integrated assessment guidance aligned with standards and informed by 25+ years of field experience with DFR technology.

What does DFR mean?

DFR stands for Dielectric Frequency Response. The test is also known as FDS (Frequency Domain Spectroscopy). DFR is a measurement technique in which capacitance and losses (expressed as dissipation factor/tan delta or power factor) are measured over multiple frequencies to assess the insulation condition in test objects, such as power transformers, bushings and instrument transformers. DFR technology is an established test procedure in laboratories that, in an innovative effort by Megger, has been adapted for field use through the IDAX range of instruments. In transformers, bushings and instrument transformers, issues are not often visible at conditions at which it is easy to perform diagnostic tests (typically, at ambient temperature and line frequency). Rather, problems are generally best exposed at higher temperatures or closer to the operational limits of the objects. Unfortunately, temperature is not easily or efficiently controlled in a field test environment. The power of a DFR test is that tan delta or power factor is the basis for its measurements. Tan delta or power factor is primarily a function of insulation system geometry, aging byproducts, moisture, liquid insulation conductivity, frequency, and temperature. Capitalising on knowledge about these relationships, an assessment of aging byproducts, moisture and conductivity can be made in the frequency domain, via DFR, rather than in the much more difficult to control temperature domain. Therefore, DFR makes it easy to find problems in the insulation under conveniently achieved conditions in the field.

IDAX322 Datasheet

FRAX99, Frax101 and Frax150

Sweep Frequency Response Analyzers

  •  Highest dynamic range and accuracy in the industry
  •  Smallest and most rugged FRA instrument in the industry
  •  Fulfills all international standards for SFRA measurements
  •  Advanced analysis and decision support built into the software
  •  Imports data from other FRA test sets

The FRAX series of sweep frequency response analyzers (SFRA) detects potential mechanical and electrical problems that other methods are unable to detect. Major utilities and service companies have used the FRA method for more than a decade. The measurement is easy to perform and will capture a unique fingerprint of the transformer. The measurement is compared to a reference fingerprint and gives a direct answer if the mechanical parts of the transformer are unchanged or not. Deviations indicate geometrical and/or electrical changes within the transformer.

FRAX Series Details

DELTA4000 Series

12 kV Insulation Diagnostic System

  • 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

DELTA4000 Series Details


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