产品概述 Product overview

XL-21 型低压动力配电柜适用于发电厂及工矿企业中，在交流电压 500 伏及以下的三相四线或三相五线系统作动力配电之用。XL-21 型低压动力配电箱系户内装置靠墙安装，屏前检修。 

XL-21 low-voltage power distribution cabinet is suitable for power distribution in power plants and industrial and mining enterprises in three-phase four-wire or tn-s systems with AC voltage of 500 volts or less. XL-21 type low voltage power distribution box is installed against the wall and overhauled in front of the screen.

结构特点 Design feature

XL-21 型低压动力配电柜系封闭式，外壳用钢板弯制而成，刀开关操作手柄装于箱前右柱上部，可以作为切换电源之用。配电箱前面装有一只电压表，指示母线的电压。配电箱前面有门，门打开后，配电箱内全部设备敞露、便于检修维护。本配电箱均采用国内自行设计的型组件，具有结构紧凑，检修方便，线路方案可以灵活组合等特点。配电箱除装有空气断路器和熔断器作为短路保护外，还装有接触器和热继电器，箱前门可装操作按钮和指示灯。 

XL-21 type low voltage power distribution cabinet is enclosed and its shell is made of bent steel plate. The knife switch operating handle is installed on the upper part of the right column in front of the cabinet and can be used for switching power supply. A voltmeter is installed in front of the distribution box to indicate the voltage of the bus. There is a door in front of the distribution box. After the door is opened, all equipment in the distribution box will be exposed for easy maintenance. This distribution box adopts domestic self-designed components, featuring compact structure, 

convenient maintenance and flexible combination of circuit schemes. The distribution box is equipped with air switch and fuse as short-circuit protection, contactor and thermal relay. The front door of the box can be equipped with operation buttons and indicator lights.

正常使用环境 Normal operating environment

◇ 环境温度：-50℃ ~+40℃，且 24h 内的平均温度不超过 +36℃； 

◇海拔高度：不超过 2000m； 

◇相对湿度：在周围空气湿度为 +40℃时不超过 50%； 

在较低湿度下可以有较高的相对湿度 ( 如：+20℃时为 90%)，考虑 到温度的变化允许产生适度的凝霜： 

◇设备安装时与垂直面的倾斜度应不超过 5°，设备应安装在无剧烈震动、无冲击及无腐蚀的场所。 

◇ Ambient temperature: -50℃ ~+40℃ , and the average temperature within 24 hours shall not exceed+36℃ ; 

◇ Altitude: no more than 2000 m; 

◇ Relative humidity: not more than 50% when ambient air humidity is +40℃ ; 

Under lower humidity, it can have higher relative humidity (e.g.: +20℃ is 90%). Considering the change of temperature, it is allowed to produce moderate frost: 

◇ The inclination of the equipment to the vertical plane shall not exceed 5 during installation, and the equipment shall be installed in a place free from severe vibration, impact and corrosion.

使用、维护和检修 Use, maintenance and overhaul

动力配电箱在安装或检修后，在投入运行前须进行下列各项检查与试验 ( 检修后的检查与试验，视其检修质性而定 )。 

◇ 检查动力配电柜内部装设电器设备和二次接线是否符合图纸要求。 

◇ 检查用于操作的刀开关、空气开关是否灵活，应无卡轧型象。 

◇ 检查所装设的电器设备的接触是否良好，是否符合该电器设备的本身使用要求。 

◇ 检查动力配电柜内部有无其他异物及各部分坚固螺钉是否有松动现象。 

After the power distribution box is installed or overhauled, the following inspections and tests shall be carried out before it is put into operation (the inspections and tests after overhaul depend on the quality of overhaul). 

◇ Check whether the electrical equipment and secondary wiring installed inside the power distribution cabinet meet the drawing requirements. 

◇ Check whether the knife switch and air switch used for operation are flexible, and there should be no sticking and rolling pattern. 

◇ Check whether the electrical equipment installed has good contact and meets the use requirements of the electrical equipment itself. 

◇ Check whether there are any other foreign matters in the power distribution cabinet and whether the strong screws in each part are loose.