1. Why seldom use high-voltage circuit breakers in European box transformers?

Because high voltage circuit breaker plays two main roles in power system: breaking normal load current and breaking short circuit current, and the high voltage switch of power system terminal users, especially those with small and medium capacity of 10kV, often breaks normal load current, and the situation of breaking short circuit current is very few, so high voltage load switch and fuse combination are used to replace high voltage circuit breaker. Voltage load switch realizes breaking normal load current, and fuse realizes breaking short circuit current.

High-voltage load switch and fuse combination can replace high-voltage circuit breaker and realize the function of disconnector. Compared with high-voltage load switch and fuse combination, high-voltage circuit breaker with large size and high cost is not suitable for the requirements of European box transformer. More than 95% of the Euro-type box-to-high voltage equipment adopt high-voltage load switch.

2. What are the main types of high-voltage load switches for Euro-box transformers?

See table below.

Load Switch Type Gas-producing Load Switch Pneumatic Load Switch Vacuum Load Switch SF6 Load Switch

Typical representative products FN5, FN8 and other FN12, VEI FN21, ZFN 8DJ20

Arc-extinguishing mode arc ignition produces a large amount of gas arc-extinguishing switch motion compressed air arc-extinguishing vacuum arc-extinguishing SF6 arc-extinguishing

Low reliability is generally the highest

Shortest and longest service life

Domestic products in 1970s, domestic products in 1990s, imported products in 1996, unified design products of Xigao Institute, imported foreign products are relatively mature.

Accessories can not be equipped with electric operation and release coil. Electric operation and release coil can be equipped with electric operation and release coil. Electric operation, release coil and FTU can be installed with release coil.

Lowest price, higher price