इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 13778-4 (2011): Winding Wires - Test Methods, Part 4: Chemical properties [ETD 33: Winding Wire] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 Hkkjrh; ekud os"Vu ijh{k.k i)fr;k¡ — HHHHHkkkkkkkkkkxxxxx 44444 jjjjjkkkkklllllkkkkk;;;;;fffffuuuuuddddd xxxxxqqq..qq...kkkkk /////kkkkkeeeeeZZZZZ ¼ igyk iqujh{k.k ½ Indian Standard WINDING WIRES — TEST METHODS PART 4 CHEMICAL PROPERTIES ( First Revision ) ICS 29.060.10 © BIS 2011 BU R E AU O F I N D I A N S TA N DA R D S MANAK BHAVAN, 9 B AHADUR SHAH ZAFAR MARG NEW DELHI 110002 NNNNNNNNNNNNNNNNNND e c ember 2011 Price Group 6 Winding Wires Sectional Committee, ETD 33 NATIONAL FOREWORD This Indian Standard (Part 4) (First Revision) which is identical with IEC 60851-4 : 2005 ‘Winding wires — Test methods — Part 4: Chemical properties’ issued by the International Electrotechnical Commission (IEC), being a consolidated version it also includes Amendment No. 1 in 1997 and Amendment No. 2 in 2005, was adopted by the Bureau of Indian Standards on the recommendation of the Winding Wires Sectional Committee and approval of the Electrotechnical Division Council. This standard was first published in 1994. This revision has been undertaken with a view to bring it in line with the latest version of IEC 60851-4 : 2005. The text of IEC Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following: a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’. b) Comma (,) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (.) as the decimal marker. In this adopted standard, reference appears to certain International Standards for which Indian Standards also exist. The corresponding Indian Standards which are to be substituted in their respective places are listed below along with their degree of equivalence for the editions indicated: International Standard Corresponding Indian Standard Degree of Equivalence IEC 60296 : 1982 Specification for IS 335 : 1993 New insulating oils — Technically Equivalent unused mineral insulating oils for Specification (fourth revision) transformers and switchgear IEC 60554-1 : 1977 Specification for IS 9335 (Part 1) : 1979 Specification do cellulosic papers for electrical for cellulosic papers for electrical purposes — Part 1: Definitions and purposes: Part 1 Definitions and general general requirements requirements IEC 60851-1 : 1996 Winding wires — IS 13778 (Part 1) 2010 Winding wires Identical Test methods — Part 1: General — Test methods: Part 1 General (first revision) IEC 60851-3 : 1996 Winding wires — IS 13778 (Part 3) : 1993 Methods of Technically Equivalent Test methods — Part 3: Mechanical test for winding wires: Part 3 Mechanical properties properties IEC 60851-5 : 1996 Winding Wires — IS 13778 (Part 5) : 1993 Methods of do Test methods — Part 5: Electrical test for winding wires: Part 5 Electrical properties properties Only English language text has been retained while adopting it in this Indian Standard, and as such the page numbers given here are not the same as in the IEC publication. (Continued on third cover) IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 Indian Standard WINDING WIRES — TEST METHODS PART 4 CHEMICA L PROPERTIES ( First Revision ) 1 Scope This part of IEC 60851 specifies the following tests: – Test 12: Resistance to solvents; – Test 16: Resistance to refrigerants; – Test 17: Solderability; – Test 20: Resistance to transformer oil. For definitions, general notes on methods of test and the complete series of methods of test for winding wires see IEC 60851-1. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60296:1982, Specification for unused mineral insulating oils for transformers and switchgear IEC 60554-1:1977, Specification for cellulosic papers for electrical purposes – Part 1: Definitions and general requirements IEC 60851-1:1996, Winding wires – Test methods – Part 1: General IEC 60851-3:1996, Winding wires – Test methods – Part 3: Mechanical properties IEC 60851-5:1996, Winding wires – Test methods – Part 5: Electrical properties 3 Test 12: Resistance to solvents (applicable to enamelled round wire with a nominal conductor diameter over 0,250 mm and applicable to enamelled rectangular wire) The test is not suitable for round wires with a nominal conductor diameter up to and including 0,250 mm. Resistance to solvents is expressed by the pencil hardness of the wire after solvent treatment. 3.1 Equipment The following solvents shall be used: – standard solvent as specified below, or – solvent as agreed between purchaser a nd supplier. 1 IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 The standard solvent shall be a mixture of: – 60 % by volume white spirit with maximum aromatic content of 18 %; – 30 % by volume xylene; – 10 % by volume butanol. The pencil to be used shall be a lead pencil of a hardness as specified in the relevant standard. Before each test, the point of the pencil shall be sharpened with a smooth-cut file to form an angle of 60° symmetrical about the axis of the lead according to Figure 1. 3.2 Procedure A straight piece of wire, approximately 150 mm in length, shall be preconditioned for (10 ± 1) min at (130 ± 3) °C in an oven with forced air circulation. A substantial length of the wire shall then be immersed in standard solvent contained in a glass cylinder and shall be maintained therein at a temperature of (60 ± 3) °C for a period of (30 ± 3) min. The wire shall then be removed from the solvent. The hardness of the wire surface shall then be determined in the following manner within a period of 30 s after removal from the solvent. The specimen to be tested shall be laid on a smooth hard surface according to Figure 1. In the case of rectangular wires, the test shall be carried out on the largest side of the wire. The pencil shall be placed on the surface of the wire at an angle of approximately (60 ± 5)° and the sharpened edge shall be pressed slowly along the surface of the wire with a force of approximately (5 ± 0,5) N. Three tests shall be made. It shall be reported, if the coating is removed with exposure of the bare conductor. NOTE 1 This method can also be used for testing resistance to other fluids, for example oil. NOTE 2 Where it is desired to determine the hardness of the insulation, the hardness of the lead pencil which just fails to remove the coating from the surface of the conductor shall be taken as the hardness of the wire surface, expressed by the pencil hardness. The pencil hardness series is as follows: 6B 5B 4B 3B 2B B HB H 2H 3H 4H 5H 6H 7H 8H 9H ____________________________________________________________________________________________ 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 4 Test 16: Resistance to refrigerants (applicable to enamelled round wire) Resistance to refrigerant is expressed by the quantity of matter extracted from the coating of the wire and by the breakdown voltage after exposure to a refrigerant. NOTE 1 The data in this test method apply to monochlorodifluoromethane (refrigerant R 22). Other refrigerants may be used, in which case the critical data for such fluid should be observed and operation of the pressure vessel should comply with the revised test conditions. NOTE 2 Refrigerants like monochlorodifluoromethane and rinsing fluids like trichlorotrifluorethane (refrigerant R 113) are ozone depleting chemicals (ODC). Refrigerant and rinsing fluid should be agreed upon between customer and supplier. 4.1 Extraction 4.1.1 Principle A siphon cup containing the wire sample is placed in the pressure vessel. The extractable matter is determined after exposure of the wire sample to the refrigerant under pressure and at elevated temperature. 2 IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 4.1.2 Equipment The following equipment shall be used: – siphon cup according to Figure 2, of 450 ml volume up to the siphoning level; – pressure vessel of 2 000 ml volume with an internal diameter of approximately 100 mm and a pressure capacity of 200 bar (20 MPa), preferably of unwelded construction and provided with a controlled heating system; – top closure of the vessel containing a condenser coil according to Figure 3; – oven with forced air circulation. 4.1.3 Specimen Eight wire samples each containing (0,6 ± 0,1) g of insulation shall be wound into coils of 70 turns. The specimens shall be degreased and conditioned in an oven with forced air circulation at (150 ± 3) °C for 15 min. After 30 min cooling, the eight specimens shall be weighed together to the nearest 0,0001 g, resulting in the total initial mass M . 1 4.1.4 Procedure The eight specimens shall be placed in the siphon cup, which is suspended (25 ± 5) mm below the condenser coil on the pressure vessel cover. The pressure vessel shall be assembled and charged with (700 ± 25) g of distilled refrigerant free from lubricant. The condenser water supply and drain line shall be connected and the pressure vessel shall be heated by means of a controlled heating system with the temperature set to (75 ± 5) °C or a lower temperature if required to comply with the conditions of the following paragraph relating to critical pressure. The water flowing through the condenser shall be adjusted to maintain a reflux rate of 20 to 25 discharges per hour from the siphon cup. The extraction period shall be 6 h. The pressure in the vessel shall not exceed 75 % of the critical pressure of the refrigerant chosen. Therefore, prior to use, the over-pressure control valve shall be checked to ensure its proper functioning. NOTE It is recommended that the heating system be automatically deactivated if the pressure exceeds 75 % of the critical pressure of the refrigerant chosen or if the water flow through the condenser coil is interrupted. At the end of the extraction period the pressure vessel shall be cooled. The refrigerant shall be removed from the pressure vessel and recovered using suitable means such as a refrigerant compressor and recovery system. The pressure shall be released and the pressure vessel opened. For the following operations, the rinsing fluid shall be distilled before use. The specimens and siphon cup shall be rinsed with the agreed rinsing fluid, the rinse poured into the pressure vessel and the walls of the pressure vessel washed with two successive rinses each of 100 ml of rinsing fluid. The fluid shall then be evaporated to (5 ± 1) mm from the bottom of the pressure vessel and recovered in a safe manner. The liquid sample shall be transferred to a pre-dried tared aluminium weighing dish and the pressure vessel rinsed with 15 ml of rinsing fluid, which is transferred to the dish and then evaporated to dryness at (150 ± 3) °C for 60 to 65 min. The weighing dish shall then be cooled to room temperature in a desiccator. The dish with the residue shall be weighed to the nearest 0,0001 g and the original tared mass of the same dish subtracted. The difference is the total residue mass M of the matter extracted from the eight specimens. 2 3 IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 The insulation on the coils shall be removed by suitable chemical means not affecting the conductor and the bare conductors shall be dried at (150 ± 3) °C for (15 ± 1) min and cooled to room temperature in a desiccator. They shall be weighed to the nearest 0,0001 g and the mass of the eight conductors together is the total conductor mass M . 3 4.1.5 Result The extractable matter shall be determined according to the following equation: M Extractable matter = 2 × 100 % M −M 1 3 One test shall be made. The masses M , M , M , the refrigerant, rinsing fluid, temperature, 1 2 3 pressure of the pressure vessel and the percentage extractable matter shall be reported. 4.2 Breakdown voltage 4.2.1 Principle A specimen prepared according to 4.4.1 of IEC 60851-5 is placed in a pressure vessel according to 4.2.2. The breakdown voltage is determined after exposure of the specimen to the refrigerant under pressure and at elevated temperature. 4.2.2 Procedure The specimen shall be conditioned in the oven (150 ± 3) °C for 4 h and then placed in the pressure vessel, which shall be assembled and charged with (1 400 ± 50) g of refrigerant. The pressure vessel shall be heated according to 4.1.4 of this standard but for a period of (72 ± 1) h. At the end of the exposure period, the pressure vessel shall be cooled and discharged as described under 4.1.4. When the pressure inside the tube is less than 2 bar (0,2 MPa) absolute, the pressure vessel shall be opened and the specimen, within a period of 25 s to 30 s, transferred to the oven at a temperature of (150 ± 3) °C. The specimen shall remain in the oven for (10 ± 1) min. After the specimen is removed from the oven and allowed to cool to room temperature, the breakdown voltage shall be determined according to 4.4.1 of IEC 60851-5. 4.2.3 Result Five specimens shall be tested. The five individual values shall be reported. 5 Test 17: Solderability (applicable to enamelled round wire and bunched wire) Solderability is expressed by the time of immersion of the specimen in a solder bath required to remove the coating and to coat the conductor with solder. Safety warning: Chemical hazard – Lead has been recognized by regulatory agencies to be a hazardous substance. Primary routes of exposure are by inhalation and ingestion. The information contained in the Material safety data sheet (MSDS) for lead, tin, flux and alcohol must be adhered to while using, handling or disposing of these products. Adequate ventilation or forced exhausting of solder pot vapours and products of decomposition from various solderable insulations may be necessary to comply with environmental regulations. Safety warning: Thermal hazard – Care must be exercised in removing test specimens from the solder pot to avoid skin burns. 4 IS 13778 (Part 4) : 2011 IEC 60851-4 : 2005 5.1 Equipment The following equipment shall be used: – temperature controlled solder bath of sufficient volume to maintain a constant solder temperature when immersing the specimen at any temperature specified in the relevant standard. Solder composition shall be of a mass ratio of 60 parts tin to 40 parts lead; – any specimen holder that holds the wire under test free for at least 20 mm between the points of support when immersed into the solder. The material used for the specimen holder shall be such that the solder does not undergo any contamination and the dimensions of the holder shall not lead to significant change of the bath temperature during immersion. NOTE Contamination of the solder due to oxidation or from copper may affect the results. 5.2 Equipment The following equipment shall be used: – Temperature controlled solder bath of sufficient volume to maintain a constant solder temperature when immersing the specimen at any temperature specified in the relevant standard. Solder composition shall be of a mass ratio of 60 parts tin to 40 parts lead; any dross which forms shall be removed from the surface of the solder before each test; the temperature shall be controllable with ±5 °C of the relevant specification temperature. – Any suitable carrier that allows the wire to be held free for at least (35 ± 5) mm between the points of support (see Figure 4). The material used for the carrier shall be such that the solder bath does not undergo any contamination. The dimensions of the carrier shall not lead to appreciable changes in the bath temperature during immersion. NOTE Contamination of the solder due to oxidation or from copper may affect the results. 5.3 Procedure The specimen shall be held vertically over the centre of the bath maintained at the temperature as specified in the relevant standard. The bottom end shall be lowered to (35 ± 5) mm below the surface of the bath. The position at which the specimen is immersed shall be within 10 mm of the point where the temperature is measured. After immersion for the time specified in the relevant specification sheet, the specimen shall be moved sideways in the bath before it is withdrawn from the solder. The surface of the tinned wire shall be examined with a magnification of 6X to 10X. In the case of wire up to and including 0,100 mm nominal conductor diameter, the examination shall be restricted to the centre (25 ± 2,5) mm free length section between the supports. In the case of wire over 0,100 mm nominal conductor diameter and bunched wires, the examination shall be restricted to the lower 15 mm of the segment immersed in the pot. Three specimens shall be tested. The condition of the surface of the wire shall be reported. 5