XL21 power distribution cabinet is mainly used in industrial and mining enterprises. AC frequency 50Hz, voltage below 500 three-phase three-wire, three-phase four-wire power system, power lighting For power distribution. This product series indoor device is made of steel plate bending and welding, single left-hand door, and the knife switch operating handle is equipped with a measuring instrument on the upper door of the right column in front of the box. operating and signalling appliances. After opening the door, all electrical appliances are exposed, which is convenient for inspection and maintenance. Prevent dust and rainwater from infiltrating; the box is equipped with a mounting bottom plate, which can install electrical equipment, door The opening is more than 90° and the rotation is flexible. The incoming and outgoing lines are operated by cable wiring, which is completely reliable. 1. Main electrical performance shall completely comply with regulations of IEC60439-1:1992, GB7251.1-1997. 2. The auxiliary circuit has functions of local/remote, remote, automatic control and in-site/remote, remote control switch. The contractor can adopt DC protection. 3. Receiving the main switch has optional protection of instart trip and pyromagnetic trip. Can cancel instant protection for matching next class main-switch, avoid skip-class tripping, and has functions of motor/manual operation and automatic switch. 4. Main switch of the feeding circuit has the protection of instant trip and pyromagnetic trip. Can add fault protection if customer required 5. The motor control circuit has the protection of short-circuit instant. overload, Undervoltage release and phase-break. 6. Ammeter and voltage meter for the incoming circuit.1. Ambient air temperature: -5~+40 and the average temperature should not exceed +35 in 24h. 2. Install and use indoors. Altitude above sea level for operation site should not exceed 2000M. 3. Relative humidity should not exceed 50% at max temperature +40. Higher relative humidity is allowed at lower temperature. Ex. 90% at +20. But in view of the temperature change, it is possible that moderate dews will produce casually. 4. Installation gradient not exceed 5. 5. Install in the places without fierce vibration and shock and the sites insufficient to erode the electrical components. 6. Any specific requirement, consult with manufactory.