The relationship between group of insulating material and CTI

According to IEC60950, creepages distance shall be so determined that , for given RMS working voltage and pollution degree ,no flash over or breakdown of insulation (for example ,due to tracking ) will occur .

So . material groups depend on the comparative tracking index (CTI) and are classified as follows:

Material Group I:     CTI ≥ 600
Material Group Ⅱ  400 ≤ CTI 〈 600
Material Group Illa  175 ≤ CTI 〈 400
Material Group Illb  100 ≤ CTI 〈 175

The material group is verified by evaluation of the test date for the material according to IEC60112 using 50 drops of solution A .

Zhilitong Electromechanical Co., Ltd manufactures tracking index tester ZLT-LDQ1 which is complying with IEC60950 standard.
 

Comments

Post a Comment

Popular posts from this blog

What are the parts that isn’t suitable for glow wire test?

Image
On the basis of IEC 60335-1 clause 30.2.3, glow wire test apparatus of IEC60695-2-11 is not applicable to  some parts of electrical appliance as below: 1.  Parts supporting welded connections 2.  Parts supporting connections in low power circuits described in 19.11.1 3.  Soldered connection on printed circuit boards 4.  Connections on small components that are mounted on printed circuit boards 5.  Parts within 3 mm of any of these connections Note Examples of small component are diodes, transistors, resistors, integrated circuits and capacitors not directly connected to the supply mains. The glow wire test apparatus   ZLT-GTR produced by Zhilitong Electromechanical Co., Ltd , conforms to requirements of IEC60335-1 standard.
Read more

The comparison between new and old standard for glow wire tester（1)

Image
The newest IEC60695-2-10:2013 standard for   glow wire test apparatus was carried out for some years , compared with the old standard, the requirements of glow wire loop , thermocouple, silver foil test temperature has been updated. First, according to old standard , the demanded thermocouple wire diameter is 0.5 mm, but the new standards for the wire diameter requires 1.0mm, which would lead corresponding change for glow wire loop .  The thermocouples which are mounted in  glow wire test apparatus  ZLT-GTR manufactured by  ZHILITONG Electromechanical Co.Ltd , are purchased from B+B  company, with 1.0mm wire diameter, K type, insulation against ground,complying with above requirements of newest IEC 60695 standard.
Read more