TRANSFORMER TESTING SERVICE

Testing transformers is a process of verifying their performance, quality, and safety.

There are different types of tests that can be performed on transformers, depending on the purpose and application. Some of the common tests are:
Routine tests
Type tests
Special tests
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Routine tests

These are the tests that are done on every transformer to check its basic parameters and functions. They include tests such as resistance, power loss, inductance, impedance, ratio of transformation, electric strength, etc. These tests are usually done at the factory before delivery or at the site before commissioning.

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Type tests

These are the tests that are done on a representative sample of transformers to verify their design and construction. They include tests such as temperature rise, short-circuit withstand, lightning impulse, switching impulse, sound level, etc. These tests are usually done at the factory or at a special testing facility.

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Special tests

These are the tests that are done on specific transformers to gather additional information or to meet special requirements. They include tests such as dielectric response, partial discharge, dissolved gas analysis, frequency response, etc. These tests are usually done at the site or at a special testing facility.

The testing capabilities that are required for testing transformers depend on the type and scope of the tests. Some of the general capabilities that are needed are:

Measuring instruments

These are the devices that measure the electrical quantities such as voltage, current, resistance, power, frequency, etc. They should be accurate, reliable, and calibrated according to the standards.

Testing equipment

These are the devices that generate or apply the test signals such as AC or DC voltage, current, impulse, etc. They should be capable of producing the required magnitude, waveform, duration, and polarity of the test signals.

Safety equipment

These are the devices that protect the personnel and the equipment from hazards such as electric shock, fire, explosion, etc. They include devices such as fuses, circuit breakers, grounding rods, protective clothing, etc.

Data acquisition and analysis system

This system records and processes the test data and results and should be able to store, display, analyze, and report the test data and results in a clear and comprehensive manner.
At Tribhuwan Enterprises we have developed a Modern Test Laboratory to perform routine, type and special tests on Power Transformers up to 50 MVA and 132 KV class, Locomotive Transformers and single phase Traction Transformers.
The test area of our transformer test laboratory is 6.0 Mtr X 10 Mtr (Width x Length). In order to obtain grounding resistance of below 0.5 ohms, grounding rods that are connected to each other are piled under the test area. The surface of the test area is covered with steel plates which are connected to grounding rods via different points.

The following Equipment’s are used for routine, type and special tests of transformers.

  • 150 KV, 0.5 Amp single phase testing transformer.
  • 415 V ac supplied 1000 KVA, 3 phase, 0…470 V ac Variac.
  • 500 KVA, 1.1 KV….. 36 KV output, 3 phase step up Transformer.
  • 33 KV, 600 Amp Transformer loss measurement system.
  • 8.4 MVAR, 0.44 KV……..33 KV variable capacitor bank.
  • 200 KVA, 200 Hz Ac Generator set to carry out induced over voltage test.
  • Current Transformers 25-50-100-200-300-600 A/5.0 A, class 0.1, 10 VA.
  • Potential Transformers 1.1-2.2-3.3 KV/110 V, class 0.1, 50 VA.
  • Potential Transformers 11-22-33 KV/110 V, class 0.1, 50 VA.
  • Precision power Analyzer with Harmonic measurement, Accuracy 0.1%.
  • Turns Ratio measuring instrument, accuracy 0.05%, and measuring range 0.8 TO 1000.
  • Resistance measuring instrument, accuracy 0.1%, and measuring range 10^-6 TO 10^5 ohms.
  • Tan Delta and capacitance bridge, 0 – 12 KV, 5 micro farad.
    Digital Insulation Tester, 0 – 5.0 KV Dc.
The Tribhuwan Enterprises testing & engineering teams have extensive experience in providing cutting-edge services to global clients. Our testing expertise extends across a wide range of transformers. The services include tests such as resistance, power loss, inductance, impedance, ratio of transformation, electric strength, etc. Our Performance Center of Excellence provides end-to-end performance testing solutions so that our clients can have the transformers tested at the factory or on-site before delivery, before the commissioning.