故障一闭合开关后,灯泡不亮,电流表、电压表无示数。原因分析电路中各个电路元件都不能工作,一定是电路断路,具体来说,有以下几种情况:(1)电源、电流表、开关或滑动变阻器中某个元件损坏;(2)接线柱接触不良;(3)连接导线断裂。解决方法最简单的方法是用一根导线依次并联在开关、滑动变阻器、电流表以及各元件相连接的导线两端(假设电路中只有一处故障,导线不能并联在灯泡 Fault closed switch, the light bulb is not bright, ammeter, voltmeter no indication. Cause Analysis circuit of the various circuit components can not work, must be the circuit open circuit, specifically, the following situations: (1) power, ammeter, switch or sliding rheostat in a component damage; (2) poor contact with the terminal ; (3) the connecting wire is broken. The simplest solution is to use a wire in turn in parallel in the switch, sliding rheostat, ammeter and the components connected to the ends of the wire (assuming that the circuit only one fault, the wire can not be connected in parallel with the bulb