{"id":400755,"date":"2024-10-20T04:52:16","date_gmt":"2024-10-20T04:52:16","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/ieee-c57-12-90-2021\/"},"modified":"2024-10-26T08:39:49","modified_gmt":"2024-10-26T08:39:49","slug":"ieee-c57-12-90-2021","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/ieee\/ieee-c57-12-90-2021\/","title":{"rendered":"IEEE C57.12.90-2021"},"content":{"rendered":"

Revision Standard – Active. Methods for performing tests specified in IEEE Std C57.12.00(TM) and other standards applicable to liquid-immersed distribution, power, and regulating transformers are described. Instrument transformers, step-voltage and induction voltage regulators, arc furnace transformers, rectifier transformers, specialty transformers, grounding transformers, and mine transformers are excluded. Resistance measurements, polarity and phase-relation tests, ratio tests, no-load loss and excitation current measurements, impedance and load loss measurements, dielectric tests, temperature tests, short-circuit tests, audible sound level measurements, and calculated data are covered in this standard.<\/p>\n

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PDF Pages<\/th>\nPDF Title<\/th>\n<\/tr>\n
1<\/td>\nFront cover <\/td>\n<\/tr>\n
2<\/td>\nTitle page <\/td>\n<\/tr>\n
4<\/td>\nImportant Notices and Disclaimers Concerning IEEE Standards Documents <\/td>\n<\/tr>\n
7<\/td>\nParticipants <\/td>\n<\/tr>\n
9<\/td>\nIntroduction <\/td>\n<\/tr>\n
10<\/td>\nContents <\/td>\n<\/tr>\n
12<\/td>\n1. Overview
1.1 Scope
1.2 Purpose
1.3 Word usage <\/td>\n<\/tr>\n
13<\/td>\n2. Normative references <\/td>\n<\/tr>\n
14<\/td>\n3. Definitions
4. General
4.1 Types of tests
4.2 Test requirements <\/td>\n<\/tr>\n
15<\/td>\n4.3 Test sequence
4.4 Instrumentation
5. Resistance measurements
5.1 Determination of cold temperature
5.1.1 General
5.1.2 Transformer windings immersed in insulating liquid <\/td>\n<\/tr>\n
16<\/td>\n5.1.3 Transformer windings out of insulating liquid
5.2 Conversion of resistance measurements
5.3 Resistance measurement methods
5.3.1 Voltmeter-ammeter method <\/td>\n<\/tr>\n
18<\/td>\n5.3.2 Bridge method
5.4 Resistance measurement connections and reporting
5.4.1 Wye windings
5.4.2 Delta windings
5.4.3 Autotransformer windings
6. Polarity and phase-relation tests
6.1 Subtractive and additive polarity <\/td>\n<\/tr>\n
19<\/td>\n6.2 Polarity tests: single-phase transformers
6.2.1 Polarity by ratio meter <\/td>\n<\/tr>\n
20<\/td>\n6.2.2 Polarity by inductive kick
6.2.3 Polarity by alternating-voltage test <\/td>\n<\/tr>\n
21<\/td>\n6.3 Polarity and phase-relation tests: polyphase transformers
6.3.1 Polarity of polyphase transformers
6.3.2 Phase-relation tests
6.3.2.1 Test of phase relation with ratio meter
6.3.2.2 Test for phasor diagram for transformers <\/td>\n<\/tr>\n
23<\/td>\n6.3.2.3 Six-phase windings
6.3.2.4 Zigzag windings <\/td>\n<\/tr>\n
24<\/td>\n7. Ratio tests
7.1 General
7.1.1 Taps
7.1.2 Voltage and frequency
7.1.3 Three-phase transformers
7.1.4 Three-phase transformers with inaccessible neutrals <\/td>\n<\/tr>\n
25<\/td>\n7.2 Tolerances for ratio
7.3 Ratio test methods
7.3.1 Voltmeter method
7.3.2 Comparison method <\/td>\n<\/tr>\n
26<\/td>\n7.3.3 Ratio meter <\/td>\n<\/tr>\n
27<\/td>\n8. No-load losses and excitation current
8.1 General
8.2 No-load loss test <\/td>\n<\/tr>\n
28<\/td>\n8.2.1 Connection diagrams <\/td>\n<\/tr>\n
29<\/td>\n8.2.2 Voltmeter connections
8.2.3 Energized windings
8.2.4 Voltage and frequency <\/td>\n<\/tr>\n
30<\/td>\n8.3 Waveform correction of no-load losses
8.4 Temperature correction of no-load losses <\/td>\n<\/tr>\n
31<\/td>\n8.5 Determination of excitation (no-load) current
8.6 Frequency conversion of no-load losses and excitation current
9. Load losses and impedance voltage
9.1 General <\/td>\n<\/tr>\n
32<\/td>\n9.2 Factors affecting the values of load losses and impedance voltage
9.2.1 Design
9.2.2 Process
9.2.3 Temperature
9.2.4 Measurements <\/td>\n<\/tr>\n
33<\/td>\n9.3 Tests for measuring load losses and impedance voltage
9.3.1 Wattmeter-voltmeter-ammeter method <\/td>\n<\/tr>\n
35<\/td>\n9.3.2 Impedance bridge methods <\/td>\n<\/tr>\n
36<\/td>\n9.3.3 Transformer test procedures
9.3.3.1 Two-winding transformers and autotransformers <\/td>\n<\/tr>\n
37<\/td>\n9.3.3.2 Three-winding transformer <\/td>\n<\/tr>\n
38<\/td>\n9.3.3.3 Interlacing impedance voltage of a Scott-connected transformer
9.3.3.4 Test of three-phase transformer with single-phase voltage <\/td>\n<\/tr>\n
40<\/td>\n9.4 Calculation of load losses and impedance voltage from test data
9.4.1 Correction of load loss measurement due to metering phase-angle errors <\/td>\n<\/tr>\n
41<\/td>\n9.4.2 Temperature correction of load losses <\/td>\n<\/tr>\n
42<\/td>\n9.4.3 Impedance voltage
9.4.4 Frequency conversion of load losses and impedance
9.5 Zero-phase-sequence impedance
9.5.1 Zero-phase-sequence impedance tests of three-phase transformers <\/td>\n<\/tr>\n
44<\/td>\n9.5.2 Transformers with one neutral externally available, excluding transformers with interconnected windings
9.5.3 Transformers with two neutrals externally available, excluding transformers with interconnected windings <\/td>\n<\/tr>\n
46<\/td>\n9.5.4 Autotransformers
9.5.5 General test method for zero-phase-sequence impedance measurement on transformers with interconnected windings (see Rosselli [B29]) <\/td>\n<\/tr>\n
47<\/td>\n10. Dielectric tests
10.1 General
10.1.1 Factory dielectric tests
10.1.2 Test requirements
10.1.3 Measurement of test voltages <\/td>\n<\/tr>\n
48<\/td>\n10.1.4 Type of power transformer
10.1.5 Factory dielectric tests and conditions
10.1.5.1 Test sequence
10.1.5.2 Temperature
10.1.5.3 Assembly
10.1.5.4 Transformers for connection to gas-insulated equipment
10.1.6 Tests on bushings <\/td>\n<\/tr>\n
49<\/td>\n10.1.7 Dielectric tests in the field
10.2 Switching impulse test procedures
10.2.1 Number of tests
10.2.2 Switching impulse waves
10.2.2.1 Polarity <\/td>\n<\/tr>\n
50<\/td>\n10.2.2.2 Waveshape
10.2.2.3 Time to crest
10.2.2.4 Time to first voltage zero
10.2.2.5 Ninety-percent time
10.2.3 Failure detection
10.2.4 Tap connections <\/td>\n<\/tr>\n
51<\/td>\n10.2.5 Connection of neutral terminal(s) during switching impulse tests
10.3 Lightning impulse test procedures
10.3.1 General <\/td>\n<\/tr>\n
52<\/td>\n10.3.1.1 Full-wave test <\/td>\n<\/tr>\n
53<\/td>\n10.3.1.2 Reduced full-wave test
10.3.1.3 Chopped-wave test <\/td>\n<\/tr>\n
54<\/td>\n10.3.1.4 Front-of-wave test
10.3.1.5 Wave polarity
10.3.1.6 Impulse oscillograms <\/td>\n<\/tr>\n
55<\/td>\n10.3.2 Connections for impulse tests of line terminals
10.3.2.1 Terminals not being tested <\/td>\n<\/tr>\n
56<\/td>\n10.3.2.2 Windings for series or multiple connections
10.3.2.3 Windings for delta or wye connections
10.3.2.4 Tap connections <\/td>\n<\/tr>\n
57<\/td>\n10.3.2.5 Protective devices that are an integral part of the transformer <\/td>\n<\/tr>\n
58<\/td>\n10.3.3 Impulse tests on transformer neutrals
10.3.4 Detection of failure during impulse test
10.3.4.1 Ground current oscillograms
10.3.4.2 Other methods of failure detection <\/td>\n<\/tr>\n
59<\/td>\n10.4 Routine impulse test for distribution transformers
10.4.1 Terminals to be tested
10.4.2 Procedure
10.4.2.1 Method 1 <\/td>\n<\/tr>\n
60<\/td>\n10.4.2.2 Method 2
10.4.2.3 Failure detection
10.4.3 Terminals not being tested <\/td>\n<\/tr>\n
61<\/td>\n10.4.4 Windings for series or multiple connections
10.4.5 Windings for delta or wye connections
10.4.6 Tap connections
10.5 Low-frequency tests <\/td>\n<\/tr>\n
62<\/td>\n10.5.1 Induced-voltage test for transformers with series or multiple connections
10.6 Applied-voltage tests
10.6.1 Duration, frequency, and connections
10.6.2 Relief gap
10.6.3 Application of test voltage
10.6.4 Failure detection
10.7 Induced-voltage tests for distribution and Class I power transformers
10.7.1 Test duration <\/td>\n<\/tr>\n
63<\/td>\n10.7.2 Test frequency
10.7.3 Application of voltage
10.7.4 Grounding of windings
10.7.5 Need for additional induced tests
10.7.6 Failure detection
10.7.7 Special induced voltage test for distribution and Class I power transformers with a wound core <\/td>\n<\/tr>\n
64<\/td>\n10.7.7.1 Minimum test duration and application of voltage
10.7.7.2 Test frequency
10.7.7.3 Grounding of windings
10.7.7.4 Failure detection
10.8 Induced-voltage test for Class II power transformers
10.8.1 General <\/td>\n<\/tr>\n
65<\/td>\n10.8.2 Test procedure <\/td>\n<\/tr>\n
66<\/td>\n10.8.3 Connections
10.8.4 Frequency
10.8.5 Failure detection
10.9 Partial discharge measurement
10.9.1 Internal partial discharges <\/td>\n<\/tr>\n
67<\/td>\n10.9.2 Instrumentation
10.9.3 Calibration
10.10 Insulation power-factor tests
10.10.1 Preparation for tests
10.10.2 Instrumentation
10.10.3 Voltage to be applied <\/td>\n<\/tr>\n
68<\/td>\n10.10.4 Procedure
10.11 Insulation resistance tests <\/td>\n<\/tr>\n
69<\/td>\n10.11.1 Preparation for tests
10.11.2 Instrumentation
10.11.3 Voltage to be applied
10.11.4 Procedure <\/td>\n<\/tr>\n
70<\/td>\n11. Temperature-rise tests
11.1 Test methods
11.1.1 Actual loading
11.1.2 Simulated loading
11.1.2.1 Loading back method <\/td>\n<\/tr>\n
72<\/td>\n11.1.2.2 Short-circuit method <\/td>\n<\/tr>\n
73<\/td>\n11.2 Resistance measurements
11.2.1 Cold-resistance measurements
11.2.2 Hot-resistance measurements <\/td>\n<\/tr>\n
74<\/td>\n11.3 Temperature measurements
11.3.1 Ambient temperature measurements
11.3.1.1 Air-cooled transformers <\/td>\n<\/tr>\n
75<\/td>\n11.3.1.2 Water-cooled transformers
11.3.2 Liquid temperature rise determination <\/td>\n<\/tr>\n
76<\/td>\n11.3.3 Average winding temperature-rise determination <\/td>\n<\/tr>\n
77<\/td>\n11.3.4 Other temperature measurements
11.4 Correction of temperature-rise test results
11.4.1 Correction for differences between winding rated current and test current
11.4.2 Correction of liquid temperature rise for differences in required total loss and actual loss <\/td>\n<\/tr>\n
78<\/td>\n11.4.3 Correction of liquid temperature rises for differences in altitude
11.4.4 Frequency conversion of temperature-rise test results <\/td>\n<\/tr>\n
79<\/td>\n12. Short-circuit tests
12.1 General
12.2 Test connections
12.2.1 Two-winding transformers and autotransformers without tertiary windings
12.2.1.1 Fault location <\/td>\n<\/tr>\n
80<\/td>\n12.2.1.2 Fault type <\/td>\n<\/tr>\n
81<\/td>\n12.2.1.3 Tap connection for test
12.2.2 Multiwinding transformers, including autotransformers
12.2.2.1 Fault location and type <\/td>\n<\/tr>\n
82<\/td>\n12.3 Test requirements
12.3.1 Symmetrical current requirement, two-winding transformers
12.3.2 Symmetrical current requirement, multiwinding transformers, and autotransformers
12.3.3 Asymmetrical current requirement <\/td>\n<\/tr>\n
83<\/td>\n12.3.4 Number of tests
12.3.5 Duration of tests
12.4 Test procedure
12.4.1 Fault application
12.4.2 Calibration tests
12.4.3 Terminal voltage limits
12.4.4 Temperature limits <\/td>\n<\/tr>\n
84<\/td>\n12.4.5 Current measurements
12.4.6 Tolerances on required current
12.4.7 Frequency conversion of short-circuit test
12.5 Proof of satisfactory performance <\/td>\n<\/tr>\n
85<\/td>\n12.5.1 Visual inspection
12.5.2 Dielectric tests
12.5.3 Waveshape of terminal voltage and current
12.5.4 Leakage impedance <\/td>\n<\/tr>\n
86<\/td>\n12.5.5 Dissolved gas analysis (DGA)
12.5.6 Excitation current
12.5.7 Other diagnostic measurements
13. Audible sound emissions
13.1 General
13.1.1 Introduction <\/td>\n<\/tr>\n
87<\/td>\n13.1.2 Applicability
13.2 Instrumentation
13.2.1 Sound level meter
13.2.2 One-third octave filter <\/td>\n<\/tr>\n
88<\/td>\n13.2.3 Narrowband filter
13.2.4 Wind screen
13.2.5 Calibration
13.3 Test conditions
13.3.1 Test environment
13.3.2 Transformer location
13.3.3 Determination of total sound level of a transformer
13.3.3.1 No-load audible sound level <\/td>\n<\/tr>\n
89<\/td>\n13.3.3.2 Load audible sound level <\/td>\n<\/tr>\n
90<\/td>\n13.3.4 Frequency conversion of measured audible sound levels
13.4 Microphone positions
13.4.1 Reference sound-producing surface <\/td>\n<\/tr>\n
91<\/td>\n13.4.2 Safety considerations
13.4.3 First measurement position
13.4.4 Number of microphone locations
13.4.5 Height of microphone locations
13.5 Sound pressure level measurements
13.5.1 A-weighted sound pressure level measurements <\/td>\n<\/tr>\n
92<\/td>\n13.5.2 One-third octave sound pressure level measurements
13.5.3 Narrowband sound pressure level measurements
13.5.4 C-weighted sound pressure level measurements
13.5.5 Sound pressure level measurements using the sound-pressure method
13.5.5.1 Measuring ambient sound pressure level
13.5.5.2 Correction for ambient sound <\/td>\n<\/tr>\n
93<\/td>\n13.5.5.3 Wall sound reflection correction K <\/td>\n<\/tr>\n
94<\/td>\n13.5.5.4 Near-field correction <\/td>\n<\/tr>\n
95<\/td>\n13.5.6 Sound pressure level measurements using the sound-intensity method
13.5.6.1 Environmental correction <\/td>\n<\/tr>\n
96<\/td>\n13.6 Determination of audible sound level of a transformer
13.6.1 Average sound pressure level (LP)
13.6.2 Determination of total sound pressure level of a transformer
13.6.2.1 Addition of no-load and load audible sound levels
13.6.2.2 Determination of total sound pressure level of a transformer at different loading conditions <\/td>\n<\/tr>\n
98<\/td>\n13.6.3 Sound power level calculation (Lw)
13.7 Presentation of results <\/td>\n<\/tr>\n
100<\/td>\n14. Calculated data
14.1 Reference temperature <\/td>\n<\/tr>\n
101<\/td>\n14.2 Losses and excitation current
14.2.1 Determination of no-load losses and excitation current
14.2.2 Load losses
14.2.3 Total losses
14.3 Efficiency
14.4 Voltage regulation of a constant-voltage transformer
14.4.1 General
14.4.2 Reference temperature
14.4.3 Load loss watts and impedance volts <\/td>\n<\/tr>\n
102<\/td>\n14.4.4 Voltage regulation computation, two-winding transformers
14.4.4.1 Exact formula for the calculation of regulation
14.4.4.2 General expression for calculation of transformer regulation <\/td>\n<\/tr>\n
103<\/td>\n14.4.4.3 Three-phase to two-phase transformers <\/td>\n<\/tr>\n
104<\/td>\nAnnex A (informative) Partial discharge measurement using radio-influence voltage instrumentation and its failure detection
A.1 Partial discharge measurement
A.1.1 Internal partial discharges
A.1.2 Instrumentation
A.1.3 Calibration <\/td>\n<\/tr>\n
105<\/td>\nA.2 Failure detection <\/td>\n<\/tr>\n
106<\/td>\nAnnex B (normative) 50\/60 Hz frequency conversion of measured performance parameters
B.1 No-load loss and excitation current <\/td>\n<\/tr>\n
107<\/td>\nB.2 Load loss <\/td>\n<\/tr>\n
108<\/td>\nB.3 Temperature-rise test <\/td>\n<\/tr>\n
109<\/td>\nB.4 Short-circuit test <\/td>\n<\/tr>\n
110<\/td>\nB.5 Audible sound
B.5.1 A-weighted sound level conversion of no-load noise
B.5.1.1 50\/60 Hz conversion of ONAN (core) sound level
B.5.1.2 50\/60 Hz conversion of ONAF sound level
B.5.1.2.1 Conversion from 50-Hz tested sound levels to corresponding 60-Hz levels <\/td>\n<\/tr>\n
111<\/td>\nB.5.1.2.2 Conversion from 60-Hz tested sound levels to the corresponding 50-Hz levels
B.5.1.2.3 Numerical example
B.5.1.3 Load sound level conversion
B.5.2 Frequency spectrum conversion <\/td>\n<\/tr>\n
112<\/td>\nAnnex C (informative) Connections diagrams for short-circuit testing <\/td>\n<\/tr>\n
115<\/td>\nAnnex D (informative) Tap position during induced test on Class II power transformers
D.1 General <\/td>\n<\/tr>\n
116<\/td>\nD.2 Background information <\/td>\n<\/tr>\n
117<\/td>\nAnnex E (informative) Bibliography <\/td>\n<\/tr>\n
119<\/td>\nBack cover <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

IEEE Standard Test Code for Liquid-Immersed Distribution, Power, and Regulating Transformers<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
IEEE<\/b><\/a><\/td>\n2021<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":400757,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2644],"product_tag":[],"class_list":{"0":"post-400755","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-ieee","8":"first","9":"instock","10":"sold-individually","11":"shipping-taxable","12":"purchasable","13":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/400755","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/400757"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=400755"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=400755"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=400755"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}