Charges in motion from one region to another. In the water level alarm circuit I built one a little similar to this and added a relay additionally which turns off the motor of the water pump when the water tank is full. Series And Parallel Circuit Science Teaching Resources Elementary Science Activities Series And Parallel Circuits In these circuits energy is conveyed from one place to another. . E 0 within a conductor Current I 0 but not all charges are at rest free electrons can move v 10 6. Simple Current Limiter Circuit Using two transistors. Conducting path that forms a closed loop in which charges move. Or a press switch beneath the bed mattress is maintained in closed circuit status.