Xgn15-12 ring main unit is used for receiving and distributing electric energy in 3.6, 7.2, 12kV three-phase AC 50 Hz system, especially suitable for frequent operation. Its bus system is single bus, and can be derived from single bus with bypass and double bus structure. The switch cabinet meets the requirements of national standard GB3906 and international standard IEC298, and has "five prevention" locking function proposed by two parts. With reliable and reasonable, high safety performance, simple operation, convenient maintenance and other characteristics, it is a substitute product for 10kV fixed switchgear. The incoming and outgoing circuit breakers, load switches and grounding switches are spring operating mechanisms. The circuit breakers and load switches are equipped with electric operating mechanisms, and the operating power supply is   220VAC   Or 24 VDC / 110 VDC   And so on. PT   The cabinet is an air cabinet, and the protection level should reach   IP4X   Or more. The transformation ratio of voltage transformer is   10 / 0.1kv, the accuracy level of secondary side is   zero point five   The secondary capacity is   100VA，PT   The cabinet is equipped with zinc oxide arrester, which is connected to the bus side, Pt   The cabinet is equipped with heater. All switch cabinets are equipped with ammeter, Pt   The cabinet is equipped with voltmeter, which is installed in the secondary low voltage room. The cable head is a fully sealed structure with neutral grounding. Environmental conditions: 1)   Altitude: within 2500m (2)   Minimum temperature: - 40 ℃ (3)   Relative humidity: the monthly average relative humidity is not more than   90%； The daily average relative humidity is not more than   95%4)   Maximum temperature (+ 45 ℃) 5)   Earthquake intensity: 8   Degree 6)   Pollution level: III   level