Annexure- 1 (CC no. 77654)
Technical Details of Current Transformer: For item No. 1 & 2 The detailed technical specification of the current transformer to be supplied are mentioned below:
S. No. Parameter Details 1. Type Single phase 2. Installation indoor/outdoor Outdoor 3. Rated system voltage kV 220 4. Highest Equipment Voltage kV 245 5. Frequency 50Hz 6. Rated insulation levels
i) Impulse withstand test voltage (kV peak). ii) One minute power frequency withstand test voltage a) Primary winding kV (rms) b) Secondary winding kV (rms)
1050 460 3 kV for metering /4 kV for protection
7. Minimum creepage distance
i) Total (mm) ii) Protected (mm)
5600 2800
8. Rated extended primary current % 120% 9. Rated continuous thermal current 120% 10. Short time current rating
i) Rated short time thermal current ( kA) ii) Rated duration (sec.) iii) Rated dynamic current kA (peak)
40 3 102
11. Maximum temperature rise of winding at rated continuous thermal current, rated frequency and rated burden C
As per IS-2705
12. Reference ambient air temperature deg. C 50 deg. C 13. Class of insulation of winding (Minimum requirement) Class-A 14. Current transformers suitable for
i) Wind velocity Km/ph
ii) Seismic condition (Minimum requirement)
130km/Hr.
0.25g
15. Radio interference voltage microvolts Less than 1000 µV at 156 kV 16.
Minimum visible Discharge voltage level
175kV
17. Terminal box i) Degree of protection ii) Cable glands to be supplied iii) If Yes, size of cable glands for secondary winding termination. iv) Whether short circuiting links supplied Yes/No
IP-55 Yes 25mm ±1mm Yes
18.
Earthing connections Suitable for 2 nos. of 50 X 6 mm GS flat.
19. Current transformer secondary details.
S. No. Parameter Details 19.1 Number of cores 5
19.2 Rated primary current (A) for
i) Core-1 ii) Core-2 iii) Core-3 iv) Core-4 v) Core-5
800-600-400 800-600-400 800-600-400 800-600-400 800-600-400
19.3 Rated secondary current for i) Core –1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
1 Amp. For each core
19.4 It should be possible to adjust tap setting of any core independent of other core
Yes
19.5 Actual transformation ratio 800-600-400/1 19.6 Rated transformation ratio 800-600-400/1 19.7 Application
i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
Distance/diff. Distance/ diff. Metering Bus diff. Bus diff.
19.8 Accuracy class i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
PS PS 0.2S PS PS
19.9 Rated VA i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
-- -- 30 -- --
19.10 Accuracy limit factor i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
--- --- --- --- ---
19.11 Minimum knee point voltage i) Core-1, (V) ii) Core -2 , (V) iii) Core-3 , (V) iv) Core -4 , (V) v) Core-5, (V)
1350-1000-675 1350-1000-675 --- 1350-1000-675 1350-1000-675
19.12 Maximum excitation current at VK/4 i) Core-1 mA ii) Core-2 mA iii) Core-3 mA iv) Core-4 mA v) Core-5 mA
<30 <30 --- <30 <30
Other specifications:
i) All routine test will be carried out as per IS 2705 part-1 (Latest version and amendments). In addition to this supplier will carry out a) Measurement of dialectic dissipation factor and b) Oil test as per IS: 335 (latest version).
ii) Type test: Following shall constitute the type test: a) Short time current test b) Temperature rise test. c) Lighting impulse test. d) High voltage power frequency wet withstand voltage test on outdoor current transformer. e) Determination of errors or other characteristics according to the requirements of the appropriate
designation or accuracy class. f) Chopped lightning impulse test on primary winding.
The manufacturer should carry out type test or submit valid test report of type test for current transformer being offered for supply. The type test reports should be submitted or test should be carried out at NABL accredited/ OEM test laboratory.
iii) Tentative QA plan is attached in Annexure-5. However bidder will submit detailed QA plan for approval after PO placement and before manufacturing.
iv) Bidder will submit all dimensional drawings along with the offer. v) Bidder may provide details of oil sampling point to be provided in CT (if it can be provided without
hampering performance of CT as an optional feature). Note:
1) The offered equipment have to be designed, manufactured and tested as per relevant IS/IEC with latest
amendments. 2) Three nos. copies of operation, maintenance and erection manuals in Hindi / English language shall be supplied
one month prior to the dispatch of the Instrument Transformer. 3) The Bidder shall fill the response in the bidder`s response column in Annexure-2 and to be uploaded after his
authorized seal and signature. 4) The bidder shall upload the offered CT General Arrangement drawing as Annexure-3. 5) The bidder shall upload the rating Plate and Sectional view of the 220kV CT as Annexure-4.
S. No. Parameter Details 19.13 Maximum secondary resistance at
75 deg. C. i) Core-1 ohm ii) Core-2 ohm iii) Core-3 ohm iv) Core-4 ohm v) Core-5 ohm
4-3-2 4-3-2 --- 4-3-2 4-3-2
19.14 Instrument securing factor i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
--- --- <5 --- ---
20.0 The manufacturing, Marking, Rating, and Testing etc. shall be in accordance with Indian Standards.
IS-2705(Latest)
21.0 The height of CT from center of the primary terminal. 3150 ± 120 (mm) 22.0 Size & material of primary terminals Φ30x90mm long copper rod
(tinned soldered)
Annexure- 2 (CC no. 77654) Technical Details of Current Transformer:
(Bidder shall mention specifications of quoted product in the table mentioned below):
Table-1
S. No. Current Transformers Bidders specification for quoted item 1. Type 2. Installation indoor/outdoor 3. Rated system voltage kV 4. Highest Equipment Voltage kV 5. Frequency 6. Rated insulation levels
i) Impulse withstand test voltage ( kV peak). ii) One minute power frequency withstand test
voltage a) Primary winding kV (rms) b) Secondary winding kV (rms)
7. Minimum creepage distance i) Total (mm) ii) Protected (mm)
8. Rated extended primary current % 9. Rated continuous thermal current 10. Short time current rating
i) Rated short time thermal current (kA) ii) Rated duration sec. iii) Rated dynamic current kA (peak)
11. Maximum temperature rise of winding at rated continuous thermal current, rated frequency and rated burden C
12. Reference ambient air temperature deg. C 13. Class of insulation of winding (Minimum
requirement)
14. Current transformers suitable for
i) Wind velocity Km/ph
ii) Seismic condition (Minimum requirement)
15. Radio interference voltage microvolts 16.
Minimum visible Discharge voltage level
17. Terminal box i) Degree of protection ii) Cable glands to be supplied iii) If Yes, size of cable glands for secondary
winding termination. iv) Whether short circuiting links supplied Yes/No
18. Earthing connections 19. Current transformer secondary details. 19. 1 Number of cores
19. 2 Rated primary current (A) for i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
S. No. Current Transformers Bidders specification for quoted item 19.3 Rated secondary current (A) for
i) Core –1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
19.4 It should be possible to adjust tap setting of any core independent of other core
19.5 Actual transformation ratio
19.6 Rated transformation ratio
19.7 Application i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
19.8 Accuracy class i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
19.9 Rated VA i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
19.10 Accuracy limit factor i) Core-1 ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
19.11 Minimum knee point voltage i) Core-1, (V) ii) Core -2 , (V) iii) Core-3 , (V) iv) Core -4 , (V) v) Core-5, (V)
19.12 Maximum excitation current at VK/4 i) Core-1 mA ii) Core-2 mA iii) Core-3 mA iv) Core-4 mA v) Core-5 mA
19.13 Maximum secondary resistance at 75 deg. C. i) Core-1 (ohm) ii) Core-2 (ohm) iii) Core-3 (ohm) iv) Core-4 (ohm) v) Core-5 (ohm)
Bidder should mention details of Compliance of the points mentioned item sr. no. i) to vi) in the Table-2 mentioned below:
Table-2
S. No. Current Transformers Bidders specification for quoted item
19.14 Instrument securing factor i) Core-1
ii) Core -2 iii) Core-3 iv) Core -4 v) Core-5
20.0 The manufacturing, Marking, Rating, and Testing etc. shall be in accordance with Indian Standards.
21.0 The height of CT from foundation to center of the primary terminal. (If height is other than to 3150 mm, bidder shall provide the necessary arrangement. The arrangement shall be mentioned in the bidders compliance column)
22.0 Size & material of primary terminals. (The terminal clamps, mentioned in indented item sr. no.2, shall be provided as per CT primary terminal size (provided by bidder) and other ends as per 3” IPS tube and moose conductor, which are shown in the connectors drawing, Annexure-6 a & b)
S. No. Description of other specification Bidders compliance for specification i) All routine test will be carried out as per IS 2705 part-1
(Latest version and amendments). In addition to this supplier will carry out measurement of dialectic dissipation factor and oil test as per IS: 335 (latest version).
ii) Type test: Following shall constitute following type test: a) Short time current test b) Temperature rise test. c) Lighting impulse test. d) High voltage power frequency wet withstand
voltage test on outdoor current transformer. e) Determination of errors or other characteristics
according to the requirements of the appropriate designation or accuracy class.
f) Chopped lightning impulse test on primary winding.
The manufacturer should carry out type test or submit valid test report of type test for current transformer being offered for supply. The type test reports should be witness or test should be carried out at NABL accredited/ OEM test laboratory.
iii) Tentative QA plan is attached in Annexure-5. However bidder will submit detailed QA plan for approval after PO placement and before manufacturing
iv) Bidder shall submit all dimensional drawings including General arrangement, rating plate and Sectional view of 220kV CT, along with the offer.
v) Bidder may provide details of oil sampling point to be provided in CT (if it can be provided without hampering performance of CT as an optional feature).
vi) Three nos. copies of operation, maintenance and erection manuals in Hindi / English language shall be supplied one month prior to the dispatch of the Instrument Transformer.
Annexure-3 (CC no. 77654)
General Arrangement of 220kV CT
Annexure-4 (CC no. 77654)
Sectional View of 220kV CT
Annexure-5 (CC no. 77654)
Tentative QA Plan S.N. Component
& operation Characteristics Classification Type of check Quantum
of check Reference document
Acceptance norm
Format of record
Agency Remark
1 2 3 4 5 6 7 8 9 10 11 QP NO:1 MATERIALS 1 Copper
conductor Dimension Major Measurement One
sample IS:1897 & IS:7391
Within limits specified in reference documents
Recording register
OEM Review of test reports/ certificates by NPC Q.S.
Tensile strength Major Test One sample
IS:1897 & IS:7391
Recording register
OEM
Elongation Major Test One sample
IS:1897 & IS:7391
Recording register
OEM
Conductivity Major Test One sample
IS:3635 Recording register
OEM
Chemical composition
Major Test One sample
IS:191 Recording register
OEM
Conductor finish
Major Visual 100% IS:1897 & IS:7391
No scratches dents and tarnishing
Recording register
OEM
2. Insulating paper
Dimension Minor Measurement One sample
OEM Std. OEM Std. Recording register
OEM Review of test reports/ certificates by NPC Q.S.
Physical properties (Tensile strength oil absorption)
Major Test One sample
OEM Std. OEM Std. Recording register
OEM
Electric strength
Major Test One sample
OEM Std. OEM Std. Recording register
OEM
Bursting strength elongation
Major Test One sample
OEM Std. OEM Std. Recording register
OEM
Reaction with hot oil
Major Test One sample
OEM Std. No change in acidity of oil
Recording register
OEM
Physical Condition
Major Visual One sample
OEM Std. No damage, free from foreign
Register OEM
S.N. Component & operation
Characteristics Classification Type of check Quantum of check
Reference document
Acceptance norm
Format of record
Agency Remark
particles Density Major Test One
sample OEM Std. OEM Std. Register OEM
3. Oil All characteristics as per IS: 335
Minor Test One sample
IS:335 IS:335 Register OEM Review of test reports/ certificates by NPC Q.S. Witness of test by M/s OEM & review by NPC QS
Loss angle measurement
Minor Test One sample
IS:335 IS:335 Register OEM
BDV Minor Test One sample
IS:335 IS:335 Register OEM
PPM Minor Test One sample
IS:335 IS:335 Register OEM
Resistivity Minor Test One sample
IS:335 IS:335 Register OEM
Density Minor Test One sample
IS:335 IS:335 Register OEM
4. Gaskets (rubberized cork/Silicon Rubber)
Physical properties shore hardness resistance to oil dimension check ageing test compressibility &recovery factor
Major Test One sample
OEM std. OEM std. Register OEM Review of test reports/ certificates by NPC Q.S.
5. Porcelain insulator
Dimension Major Measurement 100% IS:5621 IS:5621 Register OEM Review of test reports/ certificates by NPC Q.S. Creepage
length Major Measurement One
sample 100% 100% Register OEM
Visual inspection
Major Visual 100% 100% 100% Register OEM
Acceptance and routine tests
Major Test 100% 100% 100% Register OEM
6. Tank sand steel parts
Dimensions Major Measurement 100% Mfg. Drg. Mfg. drawing
Register OEM Review of test reports/ certificates by NPC Q.S.
Pressure test D.P. test on lifting lugs
Major Measurement 100% IS:3658 IS:3658 Register OEM
S.N. Component & operation
Characteristics Classification Type of check Quantum of check
Reference document
Acceptance norm
Format of record
Agency Remark
7. Name plate Visual check Major Visual 100% OEM std. OEM std. Register OEM Review of test reports/ certificates by NPC Q.S.
8. Terminal connectors
Dimension Major Measurement 100% Approved drawing
Approved drawing
Register OEM Review of test reports/ certificates by NPC Q.S.
Q.P. NO: 2 IN PROCESS INSPECTION 2.1 CRGO Ring
Core Dimension Major Measurement 100% Design drg. Design drg. Register OEM Review of test reports/
certificates by NPC Q.S. Witness of test by M/s OEM & review by NPC QS
Magnetizing-characteristic
Major Measurement 100% Design drg. Design drg. Register OEM
2.2 Primary and secondary winding
Proper laying of conductor
Major
Visual
100%
Design drg.
Design drg.
Register
OEM Review of test reports/ certificates by NPC Q.S. Dimension
check Major measurement 100% Design drg. Design drg. Register
2.3 Tanking Dimension Major Visual 100% Design drg. Design drg. Register OEM Review of test reports/ certificates by NPC Q.S. Witness of test by M/s OEM & review by NPC QS
Clearances Major Measurement 100% Design drg. Design drg. Register OEM
2.4 Drying & impregnation
Period temperature vacuum
Critical Measurement 100% Design specification
Design specification
Register OEM Review of test reports/ certificates by NPC Q.S. Witness of test by M/s OEM & review by NPC QS
Q.P. NO: 3 FINAL INSPECTION 3.1 Conformity
with GOA drawing
Major Measurement/ visual
100% Design specification
Design specification
Register OEM Hold point, test is to be conducted in presence of NPC QS representatives & clearances to be obtained.
3.2 All fittings verification
- Major Visual 100% Design specification
Design specification
Register OEM Hold point, test is to be conducted in presence of NPC QS representatives & clearances to be obtained.
S.N. Component & operation
Characteristics Classification Type of check Quantum of check
Reference document
Acceptance norm
Format of record
Agency Remark
3.3 Routine test As per IS:2705 Major Test 100% Design spec. Design spec.
Register OEM Hold point, test is to be conducted in presence of NPC QS representatives & clearances to be obtained.
3.4 Type test: a) Lightning
impulse withstand test
As per IS : 2075
Major Test Any one sample
IS:2075 IS: 2075 Register OEM The manufacturer should carry out type test or submit valid test report of type test for current transformer being offered for supply. The type test reports should be witness or test should be carried out at NABL accredited/ OEM test laboratory.
b) Visible discharge test
IS: 2099 Major Test Any one sample
IS: 2099 IS: 2099 Register OEM
c) Temperature rise test
IS: 2075 Major Test Any one sample
IS: 2075 IS: 2075 Register OEM
d) Partial discharge test
IEC-44-4 Major Test Any one sample
IEC-44-4 IEC-44-4 Register OEM
e) H V power frequency voltage withstand (Wet) test
IS: 2071 part-I & II
Major Test Any one sample
IS: 2071 IS: 2071 Register OEM
f) Mechanical test on porcelain
Major Test Any one sample
Register OEM