Product Description
| Item | Unit | Data |
| Rated frequency | Hz | 50,60 |
| Power frequency with stand voltage 1min(wet)(dry) phase to
ground/fracture | KV | 80 95/95 |
|
| Lightning impulse with stand voltage | KV | 185 |
|
| Rated short circuit breaking current | KA | 25/31.5 |
| Rated short circuit witch ingcurrent | KA | 63/80 |
| Rated peak with stand current | KA | 63/80 |
| 4S short time with stand current | KA | 25/31.5 |
| Rated short circuit breaking times | times | 30 |
| Control voltage of mechanism | V | AC/DC 220 |
| Second ary circuit power frquency with stand voltage 1min | KV | 2 |
|
| Contact opening distance | mm | 18±1 |
| Contact over-travelling distance | mm | 4±0.5 |
| Opening speed | m/s | 1.4-1.8 |
| Closing speed | m/s | 0.4-0.8 |
| Contact closing bounce time | ms | ≤5 |
| Middled is tance between phases | mm | 700±2 |
| Closing/Opening time difference between three phases | ms | ≤2 |
|
| The circuit esistance of each phase | Ω | <80 |
| Closing time | ms | ≤100 |
| Opening time | ms | ≤50 |
| Weight | KG | 500 |
Vacuum circuit breakers are often used in high voltage electrical
systems to perform the same function as breakers in a home’s
electrical panel. The main function of a vacuum circuit breaker is
to cut off power to electrical outlets in case of a short circuit
or electrical malfunction to allow manual disconnection of circuits
so that they can be repaired. A notable feature of vacuum circuit
breakers is that they contain evacuated spaces.
Breaker Basics
To understand how vacuum circuit breakers work, it is important to
first understand how normal circuit breakers work. Basic circuit
breakers are made of two metal contacts linked together by a
spring-loaded mechanism that acts as trip.
The spring-loaded trip mechanism contains a mechanical heat sensor
that monitors levels of electricity passing through electrical
outlets. The mechanical heat sensor trips off the breaker when
temperature levels increase due to overloading electrical
conductors.
A magnetic sensor on the spring loaded trip mechanism trips off the
breaker in case of a short circuit. The trip mechanism helps to
control overload and short circuits by pulling the contacts apart
to stop the flow of electricity in the circuit.
Arcing Problem
Circuit breakers often arc between the contacts for a few
microseconds when they trip off pulling the electrical contacts
apart. The arcing of the circuit breaker may ionize air and make it
conduct electricity or provide a path for the electricity to go
past the breaker. This is one of the main reasons why high voltage
systems use vacuum circuit breakers because they cannot be ionized
providing a path for electricity to go past the breaker. Although
vacuum circuit breakers also experience arcing, electricity cannot
go past the breaker before the contacts pull away from each other.
Vacuum Power
As the name suggests, vacuum circuit breakers contain a vacuum
between the contacts. The vacuum is just an empty space that does
not contain any solid, liquid, or gas. A vacuum is one of the best
insulators available. It does not provide room for arcing and
electricity cannot pass through a vacuum. Therefore, a vacuum is a
suitable arc-extinguishing medium. Some high voltage breakers use a
blast of high-pressure air to blow arcs apart. Others are filled
with special oil that prevents the arcing. A considerable drawback
of the air blast breakers is that they are highly complicated. On
the other hand, oil-filled breakers are flammable and are highly
toxic in case the oil leaks.
Applications
Vacuum circuit breakers, air blast breakers, and oil-filled
breakers all perform exceptionally well in transmission lines
because these electrical systems do not trip very often. In
addition, the three types of breakers require minimal maintenance
when used in transmission line applications. However, vacuum
circuit breakers perform better than the other two types of
breakers in handling line spikes and surges. In addition, vacuum
breakers perform much better in high voltage applications that
require frequent connection and disconnection of electrical
systems.
