Passive temperature detector and alarm system

The utility model provides a passive temperature detector and an alarm system. Relating to the technical field of detectors, the passive temperature detector provided by the utility model comprises adetector body and a wire assembly. Wherein a first contact and a second contact which are oppositely arranged are arranged in the detector body, the first contact and the second contact are both connected with the wire assembly, and the detector body is prepared from at least two materials with different thermal expansion coefficients, so that the contact state of the first contact and the secondcontact is changed when the external temperature rises. The passive temperature detector provided by the utility model adopts a mechanical principle to measure temperature, does not need an external power supply, overcomes the problems that an electronic temperature detector is easy to be interfered by electromagnetic interference and electronic components are easy to be damaged, works stably andreliably, and can be used r