Ubufakazi bokuqhuma kwe-Shenhai
Ngokusekelwe ku-Comparative Tracking Index (I-CTI), izinto eziqinile zokuvikela ezisetshenziswa ezintweni zikagesi ezithuthukisiwe zingahlukaniswa zibe amazinga amathathu: I, II, kanye ne-IIa, njengoba kukhonjisiwe kuThebula 1.9. Ngokusho kwe-GB/T 4207-2012 “Izindlela Zokunqunywa Kwezinkomba Zokulandela Ugesi Zezinto Eziqinile Zokugqumisa,” a grading of commonly used insulation materials is provided, as detailed in Table 1.10.
| Material level | Compared to Traceability Index (I-CTI) |
|---|---|
| I | 600≤CTI |
| II | 400≤CTI＜600 |
| IIIa | 175≤＜400 |
Beyond this material classification, the insulation materials must also meet operational temperature requirements. If enhanced-safety electrical equipment operates under permissible abnormal conditions at its rated operational state, its maximum working izinga lokushisa should not adversely affect its mechanical and electrical properties. Ngakho-ke, the stable temperature of the insulation material should be at least 20°C higher than the equipment’s maximum operating temperature, and not lower than 80°C.
| Material level | Insulation material |
|---|---|
| I | Glazed ceramics, imica, ingilazi |
| II | Melamine asbestos arc resistant plastic, silicone organic stone arc resistant plastic, unsaturated polyester group material |
| IIIA | Ipulasitiki ye-Polytetrafluoroethylene, melamine glass fiber plastic, epoxy glass cloth board with surface treated with arc resistant paint |
Designers can select the appropriate insulation materials based on the working voltage of the electrical equipment and other related requirements. If the aforementioned materials do not meet the design needs, other materials can be tested and graded as per the standard test method (I-GB/T 4207-2012).
It’s important to note that “izinto eziqinile zokufakelwa” refer to materials that are solid during operation. Some materials, which are liquid at the time of supply and solidify upon application, are also considered solid insulation materials, such as insulating varnishes.