IEEE C57.13.2-2005 pdf free download – IEEE Standard Conformance Test Procedure for Instrument Transformers.
3. Definitions
For the purposes of this standard, the Ibilowing ten and definitions qply The ,4ivthorivasisie Die Isrinon of IEEE SumSards Terms 1811! as well as IEEE SW C57.12.h&, should he refetenccd for terms not defined in this clause
3.1 eanfermnee tes*s; Certain perfiirmance tests tried to demonstrate compliance with the applicable standards. The test specimen is normally suhjeeted to all planned routine tests pilot to initiation of the confbrmance tent pmgram.
NOTE—Thc conronnaace tan nay, or nay not, be ainular to certain design teats. Dcsnon’stnnon of margin (capabilities beyond the uaadardt is not reqnire4
4. Selection of the transformer for conformance testing
Representative samples shall he chosen jointly by the concerned parties and shall represent the typical commercial product of the manuñcturer.
Fist current or voltage transformers shall be tested, except for the case of unusual or infrequently used types in which a smaller number that is acceptable to the certifying agcnc may be taken to be representative of the type. (The certifying agency may he the manufacturer. I The sample shall be selected as to be representative of the range of ratios to be certified as conforming.
5. Basis for conformance
A tran.’,tiirmer type shall be in confornaance with the standards listed when each current or voltage transformer withstands all insulation tests specified in 7.1 and 7.2. meets the requirements for both aceur.sey and temperature rise tests specified in 7.3 and 7.4, and meets the requirements tiir mechanical rating tests specified in 7.5.
The failure of a transformer to meet the requirements of the accuracy, temperature-rise, or mechanical rating tests shall be cause to reject that rating and other ratings represented by the sample. Such rejection shall not preclude the conformance of the type in other ratings that have different design characteristics and that dii meet all test requirements.
6. Treatment of failures within test sequence
Failures occurring airing coatfotmance testing should be evaluated, and corrections should be made before any re4csting is carried out. A design change made to a transfonner to correct a failure within a teat sequence shall be evaluated for its effect on any preceding sequence.
7. Tests
Uoail’omianee tests shall consist of the following tests performed in the sequence shown on each transformer selected for tests.
7.1 Impulse tests
Inwulse tents shall tic made as specified in 8.8.5 of IEEE Std C57. 13 and at the test levels indicated for the transformer HIL as Table 2 of IEEE Sid C57.13- 1993.
7.2 Voltage withstand tests
Voltage withstand tests of primary ssindings to gmunded secondary windings and parts. including metallic case, frame, base, nameplate, mounting facilities, and the core (if accessible), shall he made as specified in 8.8.3 of IEEE Std CS?. I 3-1993 and the values indicated in Table 2 of IEEE Std (‘57.13’ 1993.
7.3 Accuracy
7.3.1 Metering accuracy of current transformers
Metering accuracy test shall be made per 81 of IEEE Sid C57,13-l993 The transfonnen shall be demagnetized and then tested at 10% and 100°. of rated primary current and with a primary current equal to the rated current multiplied by the continuous themial current tating factor, 1 eats shall he made with the mirnrnum and maximum standard metering burdens for which the manufacturer assigns the same meteflng accuracy class.
In the case of dual ratio and multi-ratio transformers, tests shall be made to seril the accuracy at all ratios assigned accuracy ratings by the manufacturer and to verify the ratio of each tap
7.3.2 RelayIng accuracy of currenl transformers
Relay accuracy classes assigned by the manufacturer shall be verified in 7.3.2.1 and 712.2.
7.3.2.1 Transformers assigned ‘C” classification
a) Check ratioper WI of IEEE Sid C57.l3-1993, bi Measure resistance of the secondary winding.
c) Teat excitation current pet 83.2 of IEEE Std C57.13-1993.
dl Using data from (hi and (ci, calculate relay accuracy per 8 1,10 of IEEE Std C57,l3-1993 to verify that the transformers meets the requirements of 6.4 of IEEE Std C57.13-1993.IEEE C57.13.2 pdf download.