接通电(dian)源，电(dian)源指(zhi)示(shi)灯(deng)(deng)亮(liang)(liang)，将(jiang)转(zhuan)换开关转(zhuan)至“自动”位(wei)置，检查控(kong)(kong)制(zhi)柜（箱）所控(kong)(kong)制(zhi)的(de)(de)电(dian)机是否按液位(wei)控(kong)(kong)制(zhi)仪的(de)(de)指(zhi)令(ling)动作。当液位(wei)达(da)到控(kong)(kong)制(zhi)液位(wei)时，对(dui)应(ying)液位(wei)指(zhi)示(shi)灯(deng)(deng)发光，相(xiang)应(ying)的(de)(de)限位(wei)控(kong)(kong)制(zhi)继(ji)电(dian)器(qi)常开触点(dian)自动闭(bi)(bi)合，二(er)次(ci)控(kong)(kong)制(zhi)回(hui)路(lu)自动接通，电(dian)机起动，同时运(yun)行(xing)(xing)指(zhi)示(shi)灯(deng)(deng)亮(liang)(liang)。当水位(wei)达(da)到停止水位(wei)时，对(dui)应(ying)的(de)(de)指(zhi)示(shi)灯(deng)(deng)发光，液位(wei)测控(kong)(kong)仪的(de)(de)对(dui)应(ying)限位(wei)控(kong)(kong)制(zhi)继(ji)电(dian)器(qi)常闭(bi)(bi)触点(dian)断开，二(er)次(ci)控(kong)(kong)制(zhi)回(hui)路(lu)开路(lu)，电(dian)机停止工作，运(yun)行(xing)(xing)指(zhi)示(shi)灯(deng)(deng)熄灭。