HIGH VOLTAGE SF6 GAS BREAKER FOR EXTERNAL INSTALLATION TYPE 8 E-1 UP TO 145 KV 
Based on a 60-year tradition of successful production and operation of high-voltage circuit breakers, the KONČAR group of companies has developed and tested SF6 circuit breakers of type 8E-1.
Unlike the previous generation of SF6 circuit breakers, the 8E-1 is characterized by additional optimization of the arc extinguishing device, a new electric drive mechanism and a very low overall weight. At customers' request, the 8E-1 switch can be supplied with one or three poles, i.e. with one or three drive mechanisms (one per pole).
Pole column
The pole column consists of an arc suppressor, silicon or porcelain support insulators, and a mechanical transmission composition. The poles are assembled, configured and tested at the factory, pre-filled with SF6 gas, and supplied in a minimum number of transport kits, which reduces assembly time at the station. A mathematical model of electric arc extinguishing was developed to meet the requirements for the creation and optimization of an arc extinguishing device operating on proven auto-compression technology.
Auto-compression arc extinguishing circuit diagram
Drive mechanism
The drive mechanism with a spring electric drive, characterized by reliability, quick and easy installation at the station and decent contact closing/opening time, is housed in a drive cabinet made of aluminum, which ensures lower weight of the circuit breaker and anti-corrosion properties. In addition to the standard accessories that can be customized to suit the customer's needs, what makes the switch unique is the presence of a test connector used for monitoring or diagnostic purposes during operation.
Information on additional monitoring equipment is provided upon customer request. 
Diagram of a spring electric drive of a switch in four characteristic positions (blue – turning on, red – opening spring):
a) both springs are unloaded;
b) the closing spring is loaded, the opening spring is unloaded;
c) the closing spring is unloaded, the opening spring is loaded;
d) both springs are loaded.
| Technical specifications | Unit | 123-145 kV | |
| Rated voltage | kV | 123 | 145 |
| Rated lightning impulse withstand voltage (1.2/50s°µ) | kV | 550 | 650 |
| Rated frequency withstand voltage | kV | 230 | 275 |
| Rated frequency | Hz | 50/60 | |
| Rated normal current | A | 3150/4000 | |
| Rated breaking current | kA | 40(50) | |
| Rated thermal current | kA | 40(50) | |
| Rated electrodynamic withstand current | kA | 100(125) | |
| Normalized switching cycle | 0-0.3s-B0-3min-B0 or B0-15s-B0 | ||
| Own shutdown time | ms | 25 | |
| Own switching time | ms | 60 | |
| Switching and mechanical wear resistance class | E2, M2 | ||
| Operating voltage | In DC | 110/125/220 | |
| Motor voltage | V DC/V AC | 110/125/220 | |
| Operating temperature range | C° | (-45)-30...+40 | |
| Applicable Standards | IEC 62271-100, IEC 62271-1 | ||
Dimensions of three-pole switch 8E1 – III
| Rated voltage | kV | 123 | 145 |
| Interpolar distance (p) | mm | 1750 | 1750 |
| Height (h1) | mm | 3038 | 3288 |
| Length (b1) | mm | 4000 | 4000 |
