The compact explosion-proof station is designed to control the switching on and off of three-phase asynchronous electric motors with a squirrel-cage rotor, operated in three-phase AC networks with an isolated transformer neutral, as well as to protect outgoing power circuits from short-circuit currents, overload and earth leakage, installed in underground workings, dangerous in terms of gas (methane) or dust.
The explosion protection of the station is ensured by placing electrical elements in a flameproof enclosure that can withstand the pressure of an explosion of a methane-air mixture and exclude the transmission of an explosion to the environment. The shell of the station has the type of explosion protection “explosion-proof shell” in accordance with GOST IEC 60079-1-2011, and complies with the general requirements for explosion-proof electrical equipment in accordance with GOST 31610.0-2014.
The type of explosion protection “intrinsically safe electrical circuit” of external intrinsically safe circuits is provided with the level “ib” in accordance with GOST 31610.11-2014.
| Parameter name | Parameter value |
|---|---|
| Rated voltage, V | 1140 |
| AC frequency, Hz | 50 |
| Number of power lines switched by disconnectors | 4 |
| Number of power outlets switched by power contactors | 6 |
| Maximum current on taps, A, | |
| – tap №1 | 600 |
| – tap №2-5 | 200 |
| – tap №6 | 80 |
| Overcurrent protection setting range, n·In | 3-12 |
| Setting range In for current overload protection, A | 6,3-750 |
| Response time of current protection against overload 6 In, sec, no more | 5 |
| Controlled value of insulation resistance in the mode of general network protection against current leakage to earth, kOhm per phase, not less than | 60 |
| Controlled value of insulation resistance in the mode of preventive control and blocking, kOhm, not less than | 100 |
| Controlled resistance value of the grounding circuit, Ohm | 50 |
| Type of power contactors | vacuum |
| Mechanical wear resistance of power contacts, cycles, not less than | 1х106 |
| Mechanical wear resistance of disconnectors, cycles, not less than | 5000 |
| Overall dimensions, mm | 2172х854х1146 |
| Station weight, kg, no more | 1700 |
| Level and type of explosion protection | IP54 |
| Level and type of explosion protection | РВ Ex db [ib Mb] I Mb |