TEST REPORT No.: 10252/E/15 - GAMMA INSULATORS...Test Report No.: 10252/E/15 2.3 Low-Frequency Voltage Wet Flashover Test 2.3.1 Test procedure Test date: 2015-06-15 The tests were

TEST REPORT No.: 10252/E/15

Test Report No.: 10252/E/15

Copies: 1+1 Pages: 18 Date: 2015-09-24

Test report is confidential and must not be passed over or transferred to any third party without written approval of the customer. Test results relate only to the tests given in presented report and do not substitute any other documents. The report shall not be reproduced except in full without written approval of the testing laboratory.

TEST REPORT No.: 10252/E/15

TEST OBJECT: Post type insulator

TYPE SPECIFICATION: 51-4F

MANUFACTURER: GAMMA Corona

DRAWING NO.: POL/46kV

DATE OF DELIVERY: 2015-05-28

TEST STANDARDS: ANSI C29.18:2013, ANSI C29.11:2012, NEMA 107:1993

TESTS WITNESSED BY: N/A


TABLE OF CONTENTS

1 LIST OF SYMBOLS ...................................................................................................................... 4

2 TESTS PERFORMED .................................................................................................................... 5

2.1 Radio-Influence Voltage Test .................................................................................................. 5

2.1.1 Test procedure .................................................................................................................. 5

2.1.2 Test results ........................................................................................................................ 5

2.2 Critical-Impulse Voltage Test.................................................................................................. 6

2.2.1 Test procedure .................................................................................................................. 6

2.2.2 Test results ........................................................................................................................ 6

2.3 Low-Frequency Voltage Wet Flashover Test .......................................................................... 7

2.3.1 Test procedure .................................................................................................................. 7

2.3.2 Test results ........................................................................................................................ 7

2.4 Low-frequency voltage dry flashover test ............................................................................... 8

2.4.1 Test procedure .................................................................................................................. 8

2.4.2 Test results ........................................................................................................................ 8

2.5 Dimension test ......................................................................................................................... 9

2.5.1 Test procedure .................................................................................................................. 9

2.5.2 Test results ........................................................................................................................ 9

2.6 Galvanizing test ..................................................................................................................... 10

2.6.1 Test procedure ................................................................................................................ 10

2.6.2 Test results ...................................................................................................................... 10

2.7 Cantilever breaking load (CBL) test ...................................................................................... 11

2.7.1 Test procedure ................................................................................................................ 11

2.7.2 Test results ...................................................................................................................... 11

3 UNCERTAINTY OF MEASUREMENTS .................................................................................. 12

4 PRODUCT DRAWING ................................................................................................................ 13

5 GRAPH ......................................................................................................................................... 14

6 TEST OBJECT AND TEST SETUP PHOTOS ........................................................................... 15

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1 LIST OF SYMBOLS

All measured voltages are corrected according to ANSI C29.1, cl. 4.2.4. All measured data including values of atmospheric conditions as well as corresponding correction factors are given in the following tables where:

Radio-Influence Voltage Test b air pressure, in inches of mercury, t temperature of air, in degrees Fahrenheit, VT test voltage, in kilovolts, RIV radio influence voltage, in microvolts.

Critical Impulse Flashover Voltage Test b air pressure, in inches of mercury, t temperature of air, in degrees Fahrenheit,

kh humidity correction factor, kd air density correction factor, VIW rated impulse-withstand voltage corresponding to the standard reference atmosphere, in

kilovolts, VCRS LI critical-impulse flashover voltage corresponding to the standard reference atmosphere, in

kilovolts. Low-Frequency Voltage Wet (Dry) Flashover Test b air pressure, in inches of mercury, t temperature of air, in degrees Fahrenheit,

kh humidity correction factor, kd air density correction factor,

r.i. average value of the measured rainfall intensity, in millimeters per minute (vertical component), RW water resistivity, in ohm-meter,

T time in seconds, VF power-frequency flashover voltage (kV), average value from five flashovers, corresponding

to the standard reference atmosphere,

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2 TESTS PERFORMED

2.1 Radio-Influence Voltage Test

2.1.1 Test procedure Test date: 2015-06-15 The tests were carried out on one post insulators according to ANSI C29.18, cl. 9.4.

Radio-influence voltage was measured at the frequency 1,0 MHz in accordance with circuit diagram in Figure 3 – 3a of NEMA No. 107, Section 3.

The test arrangement was set up according to ANSI C29.11, cl. 8.2.8 (see Figure 2).

Testing and measuring equipment: R&S – Measuring receiver Rohde & Schwarz, type ESH 2, serial No. 893268/014 T - Test transformer Fischer Köln, type 250kV, s.n. P38879 IR - Inductive regulator ČKD Praha 6/ 0 - 3 kV, 50 kVA, serial No. 1300316 Cd1/Cd2 - Capacitive divider LK-250, serial No. 001-12 Cv - coupling capacitor 2500 pF, type Elektroizolacni 2500pF/450kV, serial No. 3874 universal voltmeter Siemens, type MU 15, serial No. 879953 measuring system for atmospheric conditions Comet, serial No. 04900257 digital stop-watch Olympia, i.n. PM-172

2.1.2 Test results

Table 1 b (in Hg) 29,0

73,6 t (°F) VT (kV) RIV (µV) RIV (µV) RIV (µV)

0 4 4 4 20 4 4 4 30 4 4 4 35 4 4 4

Rated value: max. 100 µV at 15 kV/1,0 MHz

Measured values of radio-influence voltages on post insulators at test voltage 20 kV (1,0 MHz) is less then 200 µV specified by ANSI C29.19, Table 1.

Post type insulator, drawing No. POL/46kV p a s s e d radio-influence voltage test according to ANSI C29.18, cl. 9.4.

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2.2 Critical-Impulse Voltage Test

2.2.1 Test procedure

Test date: 2015-06-11 The tests were carried out on one post insulators according to ANSI C29.18, cl. 9.3. The critical impulse voltages of both polarities were determined by the up and down method with 30 impulses. The wave shape of lightning impulse voltage 1,2/50 µs is given on Graph 1. The test arrangement was set up according to ANSI C29.11, cl. 8.1.2 (see Figure 3).

Testing and measuring equipment:

Sphere gaps

R1

C1

R2

C2

C3

Test object

coaxial cable tomeasuring device

impulse generator TuR Dresden 750 kV, serial No. 862512 C2/C3 – voltage divider TuR Dresden, type SMR 10/770, serial No. 895742 measuring system Haefely, type HiAS, serial No. 175247 yard stick, range 5 m, type Assist, serial No. 393/10 measuring system for atmospheric conditions Comet, serial No. 04900257

2.2.2 Test results

Table 2

Polarity + -

b (in Hg) 29,29 29,29 t (°F) 70,3 70,3

kh 1,044 1,038 kd 0,992 0,992

VCRS LI (kV) 252 275 Rated value: critical impulse flashover 200 kV (positive)

The rated critical-impulse flashover voltage 200 kV is specified by ANSI C29.18, Table 1. The value of critical-impulse flashover voltage is higher then 92 percent of the rated critical-impulse flashover voltage, i.e. 184 kV. Test sample met the requirements. Post type insulator, drawing No. POL/46kV p a s s e d critical-impulse flashover voltage test according to ANSI C29.18, cl. 9.3.

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2.3 Low-Frequency Voltage Wet Flashover Test


Test date: 2015-06-15 The tests were carried out on one post insulators according to ANSI C29.18, cl. 9.2. The average of five flashover voltages was calculated on tested insulator. The flashover voltage was obtained by increasing the voltage linearly from zero within one minute. The test arrangement was set up according to ANSI C29.11, cl. 8.2.2.1 (see Figure 4).


Cd1

Cd2

Test object

TG


G – synchronous generator BEZ Bratislava 6 kV, 1 300 kVA, 50 Hz, serial No. BRA 20980 T – test transformer Fischer Köln 250 kV, serial No. P38879 Cd1/Cd2 – capacitive divider LK-250, serial No. 001-12 universal voltmeter Siemens MU 15, serial No. 879953 yard stick, range 5 m, type Assist, serial No. 393/10 measuring system for atmospheric conditions Comet, serial No. 04900257 conductivity meter Cond 3110, serial No. 11060082 digital stop-watch Olympia, i.n. PM-173 plastic measuring cylinder 50ml, i. No. 1/153/14 & 2/153/14

2.3.2 Test results


t (°F) 70,9 r.i. (mm/min) 5,2

RW (Ωm) 185,2 kh 1,000 kd 0,989

VF (kV) 125

Rated value: low frequency flashover 95 kV (wet)

The rated low frequency flashover voltage 95 kV is specified by ANSI C29.18, Table 1. The value of low frequency flashover voltage is higher then 90 percent of the rated wet flashover voltage, i.e. 85,5 kV. Test sample met the requirements.

Post type insulator, drawing No. POL/46kV p a s s e d low-frequency voltage wet flashover test according to ANSI C29.18, cl. 9.2.

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2.4 Low-Frequency Voltage Dry Flashover Test

2.4.1 Test procedure Test date: 2015-06-15 The tests were carried out on one post insulators according to ANSI C29.18, cl. 9.1. The average of five flashover voltages was calculated on tested insulator. The flashover voltage was obtained by increasing the voltage linearly from zero within one minute.

The test arrangement was set up according to ANSI C29.11, cl. 8.2.1.2 (see Figure 5).


Cd1

Cd2

Test object

TG


G – synchronous generator BEZ Bratislava 6 kV, 1 300 kVA, 50 Hz, serial No. BRA 20980 T – test transformer Fischer Köln 250 kV, serial No. P38879 Cd1/Cd2 – capacitive divider LK-250, serial No. 001-12 universal voltmeter Siemens MU 15, serial No. 879953 yard stick, range 5 m, type Assist, serial No. 393/10 measuring system for atmospheric conditions Comet, serial No. 04900257 digital stop-watch Olympia, i.n. PM-173

2.4.2 Test results


t (°F) 74,8 kh 1,073 kd 0,975

VF (kV) 151

Rated value: low frequency flashover 125 kV (dry)

The rated low frequency flashover voltage 125 kV is specified by ANSI C29.18, Table 1. The value of low frequency flashover voltage is higher then 95 percent of the rated dry flashover voltage, i.e. 118,8 kV. Test sample met the requirements.

Post type insulator, drawing No. POL/46kV p a s s e d low-frequency voltage dry flashover test according to ANSI C29.18, cl. 9.1

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2.5 Dimensional test


Test date: 2015-06-22

Verification of the dimensions was carried out on three insulators according to ANSI C29.18, clause 10.1.

The dimensions signed in the drawing No. POL/15kV (see Figure 1) were checked on each insulator.

Testing and measuring equipment: slide gauge 300 mm, Kinex, serial No. 2441/05 slide gauge 500 mm, Shan Brand, serial No. 884087 slide gauge 1000 mm, Kinex CZ, serial No. C11121 yard stick, range 5 m, type Assist, serial No. 393/10

2.5.2 Test results

Table 5

Dimension [mm]

Insulator No. Nominal values according

drawing [mm]

Maximum measured difference [mm]

Maximum tolerance [mm] from the drawing or calculated according

to ANSI C29.11. cl.5 1 2 3 + -

length L1 470,5 470,4 470,5 469,5 1,0 - ±17,7

length L2 60 60,1 60,1 60,0 0,1 - ±3,9

length L3 30,1 30 30,1 30,0 0,1 - ±2,7

length L4 98 98 98,1 97,0 1,1 - ±4,7

length L5 80,2 80,1 80,2 80,0 0,2 - ±5,4

diameter D1 94,3 94,2 94,3 94,5 - 0,3 ±5,3

diameter D2 73,2 73,2 73,1 73,0 0,2 - ±4,4

diameter D3 45 45 45 45,0 - - ±3,3

diameter D4 76,2 76,3 76,3 76,0 0,3 - ±4,3

diameter D5 113 113 113,1 113,0 0,1 - ±6,0

diameter D6 143,2 143 143,1 143,0 0,2 - ±7,2 Arcing distance

345 345,2 345,1 346,0 - 1,0 ±14,7

Creepage distance

978 978,5 978 978,0 0,5 - ±30,5

Maximum measured differences are lower than specified or calculated tolerances according to ANSI C29.11. clause 5.The acceptance criteria according to ANSI C29.18 clause 10.1 were met.

Post type insulator, drawing No. POL/46kV, p a s s e d the dimensional test according to ANSI C29.18, clause 10.1.

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2.6 Galvanizing test


Test date: 2015-06-22

Galvanizing test was carried out on three insulators according to ANSI C29.18, clause 10.2. Eight measurements were performed on each test specimen by method: measurement of coating thickness by the magnetic method- nonmagnetic coating of magnetic base metals. (see Figure 8)

Testing and measuring equipment: Dualscope FMP20, Helmut Fischer, serial No. SN140005438

2.6.2 Test results

Table 7 Insulator No.

1 2 3

156 µm 146 µm 120 µm 175 µm 139 µm 125 µm 128 µm 138 µm 121 µm 122 µm 121 µm 133 µm 125 µm 134 µm 128 µm 153 µm 141 µm 151 µm 161 µm 128 µm 143 µm 128 µm 129 µm 149 µm

Average value 144 µm



Average value of entire samples 138 µm

The average value on each test sample is higher than 78 µm according ANSI C29.11. cl. 9.6 table 3. The average value of entire samples is higher than 86 µm, according ANSI C29.11. cl. 9.6 table 3. Test samples met the requirements

Post type insulator, drawing No. POL/46kV, p a s s e d the galvanizing test according to ANSI C29.18, clause 10.2.

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2.7 Cantilever breaking load (CBL) test

2.7.1 Test procedure Test date: 2015-08-20 The test was carried out on one post insulators according to ANSI C29.18, clause 10.3. The load was increased at an approximately constant rate of less than 40% of the SCL of the insulator per minute. The direction of loading was free to pivot in a plane defined by the axis of the insulator and the anchoring point of the loading device (see Figure 6). The cantilever breaking load is the maximum load recorded during the test. The test sample after the cantilever breaking load test is shown in Figure 7. hydraulic loading machine Amsler, serial No. 55/9 digital stop-watch Olympia P-M172

2.7.2 Test results

Table 7

Sample No.: Cantilever failing load (kN) Type of failure

1 12,0 failure of the core

The measured value of a cantilever failing load are higher than the specified cantilever load SCL = 10 kN (2240 pounds).

Post type insulator, drawing No. POL/46kV, p a s s e d the cantilever breaking load (CBL) test according to ANSI C29.18, clause 10.3.

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3 UNCERTAINTY OF MEASUREMENTS

QUANTITY UNCERTAINTY (k=2)

Lightning impulse voltage Um

T1

T2

1,5 % 5,3 % 4,1 %

Power-frequency voltage 1,5 % Radio interference voltage 1,0 dB

Length – slide gauge - (0,2 – 300 mm) 120 µm Length – slide gauge - (0,2 – 500 mm) 123 µm Length – slide gauge - (0,5 – 1000 mm) 235 µm

Length yard stick (1 – 5000 mm) 630 µm Temperature 0,7 °C Air pressure 0,04 kPa

Relative humidity 5,3 % Time 0,7 %

Conductivity (0,1 µS/cm – 1000 mS/cm) 1,0 % Rainfall intensity 10,0 %

Measuring galvanizing (0- 2000 µm) 6,7 % Mechanical load – Amsler 1,0 %

The reported expanded uncertainty of measurement is stated as the standard uncertainty of measurement multiplied by the coverage factor k = 2, which for a Normal (Gaussian) distribution corresponds to a coverage probability of approximately 95 %.

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4 PRODUCT DRAWING

Figure 1

Post type insulator, drawing No. POL/46kV

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5 GRAPH

Graph 1 The wave shape of the lightning impulse

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6 TEST OBJECT AND TEST SETUP PHOTOS

Figure 2

Post type insulator, drawing No. POL/28kV, test arrangement during radio-influence voltage test

Figure 3

Post type insulator, drawing No. POL/28kV, test arrangement during lightning impulse voltage test

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Figure 4

Post type insulator, drawing No. POL/28kV, test arrangement during low-frequency voltage wet flashover test

Figure 5

Post type insulator, drawing No. POL/28kV, test arrangement during low-frequency voltage dry flashover test

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Figure 6

Post type insulator, drawing No. POL/46kV, test arrangement during cantilever breaking load (CBL) test

Figure 7

Post type insulator, drawing No. POL/46kV, test arrangement after cantilever breaking load (CBL) test

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Figure 8

Post type insulator, drawing No. POL/46kV, test arrangement during galvanizing test

- end of test report -

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Documents

TEST REPORT No.: 10252/E/15 - GAMMA INSULATORS...Test Report No.: 10252/E/15 2.3 Low-Frequency Voltage Wet Flashover Test 2.3.1 Test procedure Test date: 2015-06-15 The tests were