Transformer  Tap Changer & Winding Analyzer

  • Product No:TWA Series
  • Manufacturer:IBEKO Power AB (DV-Power)

The TWA series instruments are designed for six-winding resistance measurement of power and distribution transformers. As well as resistance measurement of inductive test objects. In addition, they provide powerful tap changer analysis options by using proprietary, non-intrusive DVtest features. They generate true DC ripple free current with automatically regulated measurement and discharging circuit.


The transformer measurements performed with the TWA instruments require only one single-step cable setup. Each transformer configuration has a special measurement algorithm. They are optimized for the fast stabilization of test results. The test current can be automatically passed through the HV and LV winding simultaneously in order to achieve shorter stabilization times.


The TWA40D model is a true three-phase instrument capable of simultaneously measuring winding resistances of three phases of YN configuration. As well as three-phase tap changer analysis. All TWA instrument models are capable of both single-phase and three-phase demagnetization. The DV-Win software, provides full control of all TWA functions from a PC and additional test and analysis modes and features, is included with the TWA instruments.


  • Resistance measurement of all tap positions in all

  • six windings performed in a single test

  • True three-phase on-load tap changer dynamic resistance measurement

  • Extremely quick measurement, single-step cable setup Automatic discharge process

  • Rapid automatic demagnetization

  • Built-in tap changer control unit

  • Temperature measurement channel





Winding Resistance Measurement
 Test currents: 5 mA – 25 A DC (TWA25A)
5 mA – 40 A DC (TWA40D)
 Output voltage: up to 55 V DC
 Measurement range: 0,1 μΩ - 10 kΩ
 Typical accuracy: ± (0,1 % rdg + 0,1 % F.S.)

Resolution
 0,1 μΩ – 999,9 μΩ: 0,1 μΩ
 1,000 mΩ – 9,999 mΩ: 1 μΩ
 10,00 mΩ – 99,99 mΩ: 10 μΩ
 100,0 mΩ – 999,9 mΩ: 0,1 mΩ
 1,000 Ω – 9,999 Ω: 1 mΩ
 10,00 Ω - 99,99 Ω: 10 mΩ
 100,0 Ω – 999,9 Ω: 0,1 Ω
 1 000 Ω – 9 999 Ω: 1 Ω

Data Storage
 1000 internal memory positions
 USB flash drive feature enables storage of
a huge number of measurements

AC Current Measurement Channel (TWA40D)
 Resolution: 0,1 ms
 Amplitude resolution: 16 bit
Current Clamp Meter Specifications
 Nominal current: 300 ARMS or 450 A DCPK
 Measuring ranges: 30/300 A
 Frequency range: DC to 20 kHz (-3 dB)
 Resolution: ± 50 / ± 100 mA
 Accuracy: ± 1% of the reading

Environmental Conditions
 Operating temperature:
-10 ºC - + 55 ºC / 14 ºF - +131 ºF
 Storage & transportation:
-40 ºC - + 70ºC / -40 ºF - +158 ºF
 Humidity 5 % - 95 % relative humidity,
non-condensing
Dimensions and Weight
 Dimensions (W x H x D):
480 mm x 197 mm x 395 mm,18 9 in x 7 8 in x 15 6 in
Weight:12,8 kg / 28.3 lbs