Chinese NPC ELECTRIC-QUALITY CONTROL

In the Material Introduction Quality Control Department, the product groups are controlled according to the specified methods by using the latest technology, calibrated devices and suitable products are released for production.

For the products to be purchased for the first time, Sample Study Method is applied with the participation of related units in order to determine the suitability of the product and to approve the order.

Materials Introduction In our Quality Control Laboratory; Conductivity measuring device, hardness measuring device, iron loss measuring device, spring tension pressing device, surface roughness measuring device, paint thickness measuring device, magnetic tester, laser meter, shortmeter, touch screen, moisture meter, calipers, micrometers and tape meters. In addition to the works carried out within our organization, our suppliers are visited on-site and the conformity of the products produced is inspected.
NPC ELECTRIC testing laboratory is an accredited laboratory in accordance with ISO/IEC 17025 standard.

Routine and type tests specified in IEEE and IEC standards, can be assessed in our test laboratories with the exception of short-circuit mechanical withstand ability type tests and special chemical transformer oil tests. Short circuits mechanical withstand ability type tests for all products groups have been conducted out at the accredited international laboraties and results have been positive.

ROUTINE TESTS

Routine tests has been applied to every transformer which is produced in line with IEEE and IEC standards.

1. Measurement of voltage ratio and check of phase displacement,

2. Measurement of winding resistance,

3. Measurement of short circuit impedance and load losses,

4. Measurement of no-load losses and no-load current,

5. Applied voltage withstand ability test ( Body test ),

6. Induced voltage withstand ability test,

7. Measurement of insulation resistance ( Megger test ),

8. Leak testing with pressure for liquit-immersed transformers,

9. Test on on-load tap changers, where appropriate,

TYPE TESTS

Type tests are applied upon customer request.

1. Temperature rise test,

2. Impulse test,

3. Measurement of no load losses and current at 90% and 110% of rated voltage,

4. Determination of sound level,

5. Measurement of power consumption of liquit pump and fans.

SPECIAL TESTS

Special tests are applied upon customer request.

1. Measurement of zero sequence impedance,

2. Measurement of oil dielectic withstand and breakdown voltage level,

3. Measurement power factor of transformer oil and solid insulation materials,

4. Paint thickness measurement,

5. Function test of alarm and protective,

6. Measurement of dissipation factor of the insulation system capacitances.

The test reports of all delivered transformers are recorded, and through our advanced archiving system, the reports of each transformer delivered in the last 25 year are available upon request. Statistics related to test is recorded and kept up to date as well.