● ZN23-40.5 MV vacuum circuit breaker is indoor MV distribution device of three-phase AC 50Hz, rated voltage 40.5kV, can be matched with JYN35/GBC-35 type  switch  cabinet.  Suitable for  control  and  protection  in  power  plant,  substation  and  power distribution system, especially suitable for frequent operation places. The vacuum circuit breaker is handcart type, with reasonable structure, convenient maintenance, safe and reliable use.

Selection

Operating conditions

1.  The environment temperature: upper limit +40℃, lower limit -15℃ (cold area -25℃);

2.  Altitude: not more than 2000m;

3.  Relative humidity: daily average value is not greater than 95%, monthly average is not greater than 90%;

4.  Saturated steam pressure: daily average value is not higher than 2.2 × 10 -3   Mpa,monthly average is not higher than 1.8×10-3 Mpa;

5.  Earthquake intensity does not exceed 8 degrees;

6.  No fire, explosion, pollution, chemical corrosion and severe vibration place.

Features

1. The overall structure of circuit breaker is handcart type, use CT19 or CD10 mechanism, can be divided into JYN1 and GBC two kinds of structure.

2. The circuit breaker body is composed of frame, insulator, vacuum interrupter, spindle and moving and static bracket. The bottom surface of the frame is equipped with 4 wheels, for moving circuit breaker, etc. the right side of the frame is equipped with 6 insulator as support, fixed moving and static support use, vacuum interrupter installed between the dynamic, static support, the circuit breaker has the characteristics of small volume, simple structure, long service life, easy maintenance, no explosion danger, no pollution etc..

Principle of operation

The circuit breaker is equipped with middle sealing longitudinal magnetic field vacuum interrupter, when the dynamic, static contact of vacuum interrupter is separated charged, contact gap will produce vacuum arc and extinguished when the current over zero. Due to the special structure of contact, the contact gap will produce appropriate longitudinal magnetic field during contact arc, the arc uniformly distributed on the surface of the contact, maintaining a low arc voltage, so that less electric corrosion speed and the arc chamber with high arc media recovery strength, improve the circuit breaker breaking short-circuit current capability and life electrical.

Technical data

Overall and mounting dimensions(mm)