To provide a sensor provided with a function which prevents an electric fire when the inside of a house is destroyed in an earthquake or the like and which warns also an excessive consumption of electricity in a normal state.

In this shock sensor 3, consumed electric power is measured by a resistance 6 to which an electric power line 1 from an ampere breaker and a neutral line 2 are connected. A signal is sent to a transmitter 9 when the consumed electric power is brought close to consumable electric power which is set by a regulator 7, and a warning is given to a receiver. In addition, when the shock sensor 3 detects a set seismic intensity and, in addition, when the sensor detects the upper-limit signal of the consumable electric power, there is a possibility of a disconnection or a leak, a CPU 4 immediately sends a sensitivity current to an earth leakage breaker, and a master earth leakage breaker is cut off.