TLW-B7S

1. APPLICATIONS

This specification is to be applied for Triple Insulated Litz Wire (TLW-B7S; hereinafter referred to as the "wire") using the winding or the wiring such as high-frequency operating electrical machine and apparatus.   

2. STRUCTURE

2.1 CONDUCTOR

The conductor shall be used the enameled stranded copper wire specified in KS C 2611^-1997 or JIS C 2529^-1991.

2.2 INSULATION

The insulation covering shall consist of triple extruded layer (1st and 2nd layer: polyester type resin, 3rd layer: thermally reinforced polyamide) which are at least equivalent thereto in quality, extruded on the surface of the conductor uniformity. The insulation layers so applied shall have no detrimental effect to the conductor and shall show no flaws or dirt. Further, the wires shall be such that the soldering is possible without removing of the insulation layer. The wire shall be satisfied with B rated (130 °C) thermal index of IEC 172 and UL SUBJECT 2353 test condition.    

2.3 COLOR

The color of the wire is basically yellow. Other colors are available on request.

3. CHARACTERISTICS

The characteristics of wire shall be satisfied with Appendix 2 value accordance with the requirements for Section 4. Other requirement of characteristics than those covered by this specification shall be as given in IEC 60950 3rd edition^-1999 (Safety of information technology equipment including electrical business equipment) sub -clause 2.10.5.4 and Annex U. The rating voltage shall be 1,000Vrms and the insulation grade shall be the reinforced (withstand test voltage 3,000Vrms for 1min). 

4. TEST

4.1 Appearance

Each winding wire shall be examined for scratch, contamination, crack and other harmful defects on the insulation by visual examination.

4.2 Dimension

The wire shall be measured the conductor diameter, insulation thickness and outer diameter as specified in KS C 3006^-1986, 5 or JIS C 3003^-1984, 5.

4.3 Spark Test

Final product shall be subjected to the spark test in accordance with the requirements for UL1581 Section 900. The test shall be performed at 3,000 Vrms.

4.4 Flexibility Test

Three samples are taken from a same lot of wire prepared in the manner described in below and tested at room temperature. A straight piece of wire at least 305 mm (12 inches) long is to be wound for 10 continuous carefully and adjacent turns around a polished mandrel of the diameter specified in Table 1. After winding, the specimen is to be examined for exposure of the base conductor or delamination by visual examination. There shall be no exposure of bare conductor, or delamination of the insulation.

After visual examination of the specimen, the sample is to be wound on the mandrel and subjected to electric strength tests at 3,000V for 1 min. The voltage shall be applied between the conductor and the mandrel.

Table 1 Mandrel diameter

4-5. Dielectric Breakdown Voltage Test

Three samples are taken from a same Lot of wire prepared in the manner described in below and tested at room temperature.

A straight piece of the final wire construction, approximately 400 mm (16 inches) in length, with the insulation removed at both ends, is to be twisted back on itself for a distance of 125 ± 5 mm (5 ± 0.2 inches) with a load applied to the wire pair, and with the number of twists, as provided in loads applied to the wire pairs and number of twists, see Table 2.

The loop at the end of the twisted section is to be cut at two places to provide a maximum spacing between the cut ends. The wire is to be subjected to a test voltage, substantially sine-wave in form, having a frequency of 60 Hz. The voltage applied between the conductors of the wires shall be raised from zero to the prescribed voltage at a rate of 500 V per second and measure the breakdown voltage.

Table 2 Loads applied to the wire and number of twists

4.6 Withstand Voltage

Two layered and three layered specimens are taken from a same Lot of wire prepared in the manner described in 4.5 Dielectric Breakdown Voltage Test and tested at room temperature.

Two layered wire shall be tested at 6,000V for 1 min and three layered wire shall be tested at 7,000V for 1 min. 

4.7 Heat Shock Test

Three samples are taken from a same Lot of wire prepared in the manner described in below and tested at room temperature.

A straight piece of wire at least 305 mm (12 inches) long is to be wound for 10 continuous and adjacent turns around a polished mandrel of the diameter specified in the Table 2. The specimen is placed into an oven with forced air circulation for a period of 30 minutes and at a temperature within 5 °C (9° F) of the temperature specified in Table 3. After removal from the oven, the specimen is to be allowed to cool to room temperature, and after cooling is to be examined for cracks under a magnification level (wire diameter 0.04~0.50, magnification level 5~10; wire diameter up to 0.5, magnification level 0~6).

After visual examination of the specimen, the sample is to be wound on the mandrel and subjected to electric strength tests at 3,000V for 1 min. The voltage shall be applied between the conductor and the mandrel.

Table 3 Oven temperature

4.8 Solvent Resistance Test

A straight piece of wire at least 200 mm (78.5 inches) long is to be thermally aged in an oven at 225   for 10 minutes. After removal from the oven, the sample is to immerse in xylene at 60 ± 3 for 30 minutes and then the specimen is to be examined for bubble or swelling on the insulation by visual examination.

Additionally, after visual examination of the specimen, the sample is to be scraped using the specified hardness of pencil lead. After test the sample is to be examined the crack through which conductor is visible by naked eye.

4.9 Solderability Test

Three straight samples are taken at random from a same Lot of wire at least 150 mm (59 inches) long are immersed in a solder melt (Sn96.5/Ag3.0/Cu0.5) at 420 ± 5 °C during the specified in Table 4. After removal from the solder melt, the specimen is to be allowed to clean using a soft dry cloth, and after cleaning is to be examined for adhesion uniformity by visual examination except the 10 mm immersed ends of specimen.

Table 4 Dipping time of Solderability Test        

5. INSPECTION

Inspection of final product shall be satisfied with Appendix 2 value accordance with the requirements for Section 4. The inspection items shall be added or omitted by customer's demand. 

6. PACKAGING

The wires shall be wound on suitable bobbin without loosen and tangle according to the conductor diameter (Appendix 1) and adequately packaged to avoid scratch or tangle during transportation. The packaged products shall be possible to permit 3 open-joint and if there is insufficient standard packaging length available to fill additional ones. However, the additional quantity shall not exceeding 30% of total supply quantity.

7. TAG of PRODUCT

Each product is attached with a tag to indicate following information

8. CAUTION of HANDLE

9. Entire Agreement & Amendments

1) This Specification shall come into force as of the date of its agreement by the customer or one month after offered to customer and effect until terminated in customer's demands. 

2) Amendments or changes to this Specification shall be valid only if made in writing and signed by an authorized signatory of each of the Parties.

Appendix 1 Specification of Wire

 Appendix 2 Summary of the test specification