BEST Test laboratory is equipped with the most advanced testing facilities and is capable of conducting all tests required by IEC standards except short circuit mechanical withstand test, conducted in an independent international laboratory, CESI-Italy.

Tests performed on the transformers can be classified as follows:
Tests during manufacturing, routine tests, type tests, special tests, acceptance tests, site tests, defect analysis / identification and tests before maintenance.

Tests during manufacturing:
Performed on all transformers after the active part assembly
completed

a) Winding resistance measurement
- after the coils are manufactured
- after the active part assembly completed.
b) Voltage ratio measurement and checking of the vector group
c) D.C. insulation resistance control

Routine Tests:
Performed on all transformers according to TS 267,
IEC 76 etc. at the end of manufacturing process

a) Voltage ratio measurement and checking of the vector group
b) Winding resistance measurement
c) Applied voltage test
d) Induced voltage test
e) No-load losses and no-load current measurement
f) Load losses and short-circuit voltage measurement
g) AC insulation loss factor and capacitance measurement
f) DC insulation resistance measurement
h) Measurement of voltage regulation and efficiency

Type Tests:
Performed upon customer request.

a) Temperature Rise Test
b) Impulse voltage withstand test

Special Tests:
Performed upon customer request.

a) Noise level measurement
b) No-load current and voltage harmonics measurement
c) Zero sequence impedance measurement
d) Partial discharge measurement
e) Transformer oil dielectric withstand measurement
f) AC insulation test of bushings
g) Fan losses measurement
h) On-load tap changer tests
i) Checking of protective and alarm equipment functions and insulation

Acceptance Tests:
Performed according to the customer requirements at the witness of the customer or his representative/s. Acceptance tests are the ones required and chosen by the customer from the above listed tests

Site Tests:
When the transformer is delivered to site and the montage is completed. Site tests are performed before start-up upon customer request.

Defect Analysis and tests before maintenance:
Performed for the defected transformers delivered to our factory and also for the transformers for which the maintenance is going to be done.