TDT 1042-10

TYPE TEST CERTIFICATE OF TEMPERATURE-RISE PERFORMANCE

OBJECT A three-phase oil-immersed type distribution transformer

TYPE 874-9717P11 SERIAL No. 1-09-142-01-0001

Rated power 500 kVA Rated voltage 11 kV ± 2 x 2,5% / 0,433 kV Connection symbol Dyn11 Rated frequency 50 Hz

MANUFACTURER United Transformers Electric Co., Riyadh, Saudi Arabia

CLIENT United Transformers Electric Co., Riyadh, Saudi Arabia

TESTED BY KEMA HIGH-VOLTAGE LABORATORY Arnhem, the Netherlands

DATES OF TESTS 12 and 13 April 2010

The object, constructed in accordance with the description, drawings and photographs incorporated in this Certificate, has been subjected to the series of proving tests in accordance with

IEC 60076-2

This Type Test Certificate has been issued by KEMA following exclusively the STL Guides. The results are shown in the record of Proving Tests and the oscillograms attached hereto. The values obtained and the general performance are considered to comply with the above Standard and to justify the ratings assigned by the manufacturer as listed on page 3.

The Certificate applies only to the object tested. The responsibility for conformity of any object having the same designations with that tested rests with the Manufacturer. This Certificate consists of 12 pages in total. © Copyright: Only integral reproduction of this Certificate is permitted without written

permission from KEMA. Electronic copies in e.g. PDF-format or scanned version of this Certificate may be available and have the status “for information only”.

The sealed and bound version of the Certificate is the only valid version.

KEMA Nederland B.V.

P.G.A. Bus KEMA T&D Testing Services Managing Director Arnhem, 13 July 2010

Ord

er N

o: 7

0971

230

Ver

sion

: 1

-2- TDT 1042-10

TABLE OF CONTENTS

TABLE OF CONTENTS .......................................................................................................................... 2

1 Identification of the test object......................................................................................................3 1.1 Ratings assigned by the manufacturer and proved by tests........................................................3 1.2 Description of the test object........................................................................................................3 1.3 List of drawings ............................................................................................................................4

2 General information......................................................................................................................5 2.1 The tests were witnessed by........................................................................................................5 2.2 The tests were carried out by.......................................................................................................5 2.3 Purpose of the test .......................................................................................................................5 2.4 Measurement uncertainty.............................................................................................................5 2.5 Applicable standards and sequence of tests ...............................................................................5

3 Temperature-rise test ...................................................................................................................6 3.1 Readings taken after total losses injection (in steady-state condition) ........................................6 3.2 Readings taken after 1 hour rated current injection .....................................................................7 3.3 Cooling-down curves taken after switch-off .................................................................................7 3.4 Calculation of average winding temperature-rise.........................................................................8 3.5 Requirements and results ............................................................................................................8

APPENDIX A MEASUREMENT UNCERTAINTIES........................................................................... 9

APPENDIX B MANUFACTURER’S DRAWINGS ............................................................................ 10

Ver

sion

: 1

-3- TDT 1042-10

1 IDENTIFICATION OF THE TEST OBJECT 1.1 Ratings assigned by the manufacturer and proved by tests Rated power 500 kVA Rated primary voltage 11 kV Rated secondary voltage 433 V Rated primary current 26,24 A Rated secondary current 667 A Rated frequency 50 Hz 1.2 Description of the test object Manufacturer United Transformers Electric Co.,

Riyadh, Saudi Arabia Designation 500 kVA Serial number 1-09-142-01-0001 Year of manufacture 2009 Number of phases 3 Insulation levels - HV winding 75 / 28 kV - LV winding - / 3 kV Tapping range ± 2 x 2,5% Number of tappings 5 Impedance voltage 4,75 % Connection symbol Dyn11 Type of cooling ONAN Primary winding material Cu Secondary winding material Cu Reference temperature 75 °C

Ver

sion

: 1

-4- TDT 1042-10

1.3 List of drawings

The manufacturer has guaranteed that the object submitted for tests has been manufactured in accordance with the following drawings. KEMA has verified that these drawings adequately represent the object tested. The following drawings are included in this Certificate. 874-9717 P11 Rev. O 721-9717 P11 Rev. O The following drawings are kept in KEMA’s files and are listed for reference only.

400-0052 E Rev. B 400-9197U11 Rev. O 265-9705U12 Rev. O 850-0001 P Rev. B 061-0393 P Rev. O 061-9705 P Rev. O 040-7041 P Rev. O 040-8072 P Rev. O 939-9705 P11 Rev. O 105-0906 E Rev. O

Ver

sion

: 1

-5- TDT 1042-10

2 GENERAL INFORMATION 2.1 The tests were witnessed by The tests have not been witnessed.

2.2 The tests were carried out by Name Company

Smeenk, S. KEMA High-Voltage Laboratory, Jansen, B. Arnhem, The Netherlands 2.3 Purpose of the test Purpose of the test was to verify whether the material complies with the specified requirements. 2.4 Measurement uncertainty A table with measurement uncertainties is enclosed in appendix A. Unless otherwise indicated in the report, the measurement uncertainties of the results presented are as indicated in this table. 2.5 Applicable standards and sequence of tests When reference is made to a standard and the date of issue is not stated, this applies to the latest issue including amendments, which have been officially published prior to the date of the tests. The sequence of the tests can be derived from the indicated dates and does not necessarily follow the sequence of presentation.

Ver

sion

: 1

-6- TDT 1042-10

3 TEMPERATURE-RISE TEST Standard and date Standard IEC 60076-2, clause 5.2.2 Test date 12 and 13 April 2010 Environmental conditions Ambient temperature 22 °C Ambient air pressure 1023 hPa Temperature of test object 22 °C Humidity 4 g/m3

Initial transformer data (in principal tapping position: 3)

DC-resistance between terminals B and C Rdc-HV 2,412 Ω (21,8 °C) DC-resistance between terminals b and c Rdc-LV 3,632 mΩ (21,8 °C) No-load losses P0 577 W Load losses Pcu 6274 W (75 °C) Total losses Ptot 6851 W Rated current In 26,24 A 3.1 Readings taken after total losses injection (in steady-state condition) sensor no. top oil (a) ambient (a) bottom oil (a) for information only (°C) (°C) (°C) phase voltages currents losses 1 51,88 22,40 38,50 (V) (A) (W) 2 49,71 22,53 39,10 U 574 27,9 2305 3 22,57 V 572 27,9 2301 4 W 575 27,8 2289 average 574 27,9 - average 50,80 22,50 38,80 total 6895

calculation of top oil and average oil temperature-rise top oil temperature-rise ∆ θ top (a) = θ top (a) - θ amb (a) 28,3 K average oil temperature-rise (a) ∆ θ oil (a) = ((θ top (a) + θ bot (a)) / 2) - θ amb (a) 22,3 K

Ver

sion

: 1

Ver

sion

: 1

-7- TDT 1042-10

3.2 Readings taken after 1 hour rated current injection sensor no. top oil (b) ambient (b) bottom oil (b) for information only (°C) (°C) (°C) phase voltages currents losses 1 50,55 22,13 37,46 (V) (A) (W) 2 48,45 22,24 37,85 U 536 26,2 2038 3 22,27 V 542 26,2 2039 4 W 539 26,2 1950 average 539 26,2 - average 49,50 22,21 37,66 total 6027

3.3 Cooling-down curves taken after switch-off

All Cooling Down Curves

y = -0,0021x3 + 0,0801x2 - 1,5799x + 62,66

y = -0,0051x3 + 0,1584x2 - 2,0734x + 62,738

52

53

54

55

56

57

58

59

60

61

62

63

0 1 2 3 4 5 6 7 8 9 10

time [min]

tem

pera

ture

[°C

]

HV Winding LV Winding

extrapolated absolute winding temperatures immediately after switch-off high voltage winding θ HV 62,7 °C low voltage winding θ LV 62,7 °C

calculation of average oil temperature average oil temperature (b) θ oil (b) = ((θ top (b) + θ bot (b)) / 2) - θ amb (b) 43,6 K

Ver

sion

: 1

-8- TDT 1042-10

3.4 Calculation of average winding temperature-rise average temperature difference winding-oil high voltage winding ∆ θ HV (cor) = θ HV - θ oil (b) 19,1 °C low voltage winding ∆ θ LV (cor) = θ LV - θ oil (b) 19,2 °C

average winding temperature-rise high voltage winding ∆ θ HV = ∆ θ HV (cor) + ∆ θ oil (a) 41,4 K low voltage winding ∆ θ LV = ∆ θ LV (cor) + ∆ θ oil (a) 41,5 K

3.5 Requirements and results item determined

(K)

guaranteed value (K)

requirementIEC 60076-2 (K)

top oil temperature-rise ∆ θ top 28 ≤ 45 ≤ 60 average winding temperature-rise HV winding ∆ θ HV 41 ≤ 50 ≤ 65 average winding temperature-rise LV winding ∆ θ LV 42 ≤ 50 ≤ 65

Result The top oil temperature-rise and the average winding temperature-rises of the windings are in compliance with the requirements.

Ver

sion

: 1

-9- TDT 1042-10

APPENDIX A MEASUREMENT UNCERTAINTIES The measurement uncertainties in the results presented are as specified below unless otherwise indicated.

measurement measurement uncertainty dielectric tests and impulse current tests

peak value: ≤ 3% time parameters: ≤ 10%

capacitance measurement tan δ measurement

0,3% ± 0,5% ± 5x10-5

partial discharge measurement < 10 pC : 2 pC 10 - 100 pC : 5 pC > 100 pC : 20%

measurement of impedance ac-resistance measurement

≤ 1%

measurement of losses ≤ 1% measurement of insulation resistance ≤ 10% measurement of dc resistance 1 µΩ - 5 µΩ : 1%

5 µΩ - 10 µΩ : 0,5% 10 µΩ - 200 µΩ : 0,2%

radio interference test 2 dB calibration of current transformers 2,2 x 10-4 Ii/Iu and 290 µrad calibration of voltage transformers 1,6 x 10-4 Ui/Uu en 510 µrad measurement of conductivity 5% measurement of temperature -50 °C - -40 °C : 3 K

-40 °C - 125 °C : 2 K 125 °C - 150 °C : 3 K

tensile test 1% sound level measurement type 1 meter as per IEC 651 and

ANSI S1.4.1971 measurement of voltage ratio 0,1%

Ver

sion

: 1

Ver

sion

: 1

Ver

sion

: 1

Ver

sion

: 1

-10- TDT 1042-10

APPENDIX B MANUFACTURER’S DRAWINGS 2 pages

drawing no. description/title date rev. 874-9197 P11 General arrangement drawing 500 kVA, 11 / 0,433 kV, 50 Hz

ground mounted transformer type 15-08-09 O

721-9197 P11 Rating & diagram plate 500 kVA, 11 / 0,433 kV, 50 Hz 15-08-09 O

Ver

sion

: 1

-11- TDT 1042-10

-12- TDT 1042-10

Ver

sion

: 1

Ver

sion

: 1

Ver

sion

: 1

Ver

sion

: 1