About Yellow Card UL Yellow Card contents 8 important properties Physical properties： 　　　　　 Electrical propertieThickness, Flammability Rating, Relative Temperature Index (RTI), Hot Wire Ignition (HWI) Electrical properties： 　　　　　High Amperage Ignition (HAI), High Voltage Track Rate (HVTR),Arc Resistance (D495), 　　　　　Comparative Tracking Index (CTI) UL 94 Flammability UL 94 V: Vertical Burn Test Method： 　　　　　Test method is to measure the comparative extinguishing characteristics of solid plastics in a vertical position. 　　　　　Results are reported as UL 94V-0 (best) through 94 V-2. UL 94 VTM: Vertical Thin Material Burn Test Method： 　　　　　Test method is developed specifically for very thin material which does 　　　　　not have enough mass to do the Vertical Burn Test. Test is very similar 　　　　　to the Vertical Burn Test Method but using a slightly larger sample, 　　　　　200mm by 40mm and hold to create a collar and so the collar strength. 　　　　　Results are also similar to the UL 94V Test Method. Consequently, 　　　　　VTM-0 (best) is equivalent to V-0 and VTM-2 is equivalent to V-2. Hot Wire Ignition Seconds, UL 746A 　　　　　 ．A hot wire of 9300C is wound on a sample test bar and 　　　　　 records the time (seconds) until the sampe ignites or burns. 　　　　　 ．UL assign PLC (Performance Level Class) codes on Yellow Card. High Amperage Arc Ignition Number of Arcs, UL 746A 　　　　　 This is to measure the average number of arcs to cause 　　　　　 the sample to ignite by applying a 240VAC, 32.5A to 2 　　　　　 electrodes at 40 arcs per minute. Relative Temperature Index 　　　　　• This is a long term (7 years) operating temperature for the material. 　　　　　• This is different from Heat Deflection Temperature (HDT) which is 　　　　　 a short term temperature under a certain pressure. Comparative Tracking Index 　　　　　This is very important parameter for electrical insulating material. 　　　　　The test is to simulate the situation that an arc trace develops in-between 　　　　　two conductors with voltage due to a surface contamination. Again, this is a thickness independent. Arc Resistance (D495) 　　　　　This is to measure the length of a conductive path generated per minute 　　　　　from two electrodes at 5,200VAC moving toward to cause a leakage during total testing time of 2 minutes. 　　　　　This test result on nominal 3.18mm thick samples can be applied 　　　　　from two electrodes at 5,200VAC moving toward to cause a leakage during total testing time of 2 minutes. 　　　　　to any other thickness. This is not relevant to most of our applications.