Indoor Epoxy Fully Enclosed Relay Protection Current Transformer LZZBJ4-35kV

LZZBJ4-35 Epoxy Resin Current Transformer for High Voltage Power Supply The current transformer is a fully enclosed product cast with epoxy resin, suitable for power system with rated frequency 50Hz or 60Hz and rated voltage 35KV, used for electric energy measurement, current measurement and relay protection. This product meets certification standards.

2. Principle of LZZBJ4-35 current transformer

LZZBJ4-35 Current transformer is epoxy resin cast fully enclosed product, suitable for power metering, current measurement and relay protection in indoor power system with rated frequency 50Hz or 60Hz and rated voltage 35kV and below. The product standard is IEC60044-1 and GB1208 "current TRANSFORMER".
The current transformer is a fully enclosed pillar structure and is a ZW7-40.5 switch special transformer.

3. Parameters of LZZBJ4-35 current transformer

1) Rated insulation level: 40.5/95/185 kV;
2) Rated secondary current: 5A,1A;
3) Rated primary current, accurate stage combination, rated output and rated dynamic and heat stable current are shown in the table:
4) Partial discharge level conforms to GB1208 "current transformer" standard;
5) Pollution grade: Ⅱ;
6, can be customized according to the user's non-standard products

4. Common faults

Common faults of current transformers are often related to manufacturing defects as follows:
1) The insulation of the current transformer is very thick, some of the insulation wrapping is loose, there are wrinkles between the insulation layers, coupled with poor vacuum treatment, impregnation is not complete, resulting in air cavity, which is easy to cause partial discharge fault.
2) The size and arrangement of capacitor screen do not meet the design requirements, or even put less capacitor screen, capacitor plate is not smooth and smooth, or even dislocation or fracture, so that its voltage sharing characteristics are destroyed. Therefore, when the electric field strength along the surface of local solid insulation reaches a certain value, it will cause partial discharge.
The direct consequence of the above partial discharge is that the insulating oil is cracked, a large amount of x wax is generated between the insulating layers, and the dielectric loss increases. This discharge has a cumulative effect, and if it continues, the characteristics of arc discharge may appear in the gas analysis of oil.
3) Because the insulation material is not clean or wet, it may produce surface discharge along its surface. This situation is more common in a terminal lead along the pad surface discharge.