Using The Ptcr Design Temperature Alarm Device

The temperature-control circuit has the widespread application in the industry and agriculture production, like in the grain warehouse's grain storage, in the granary temperature was the safe storage grain important attribute.This article elaborated the PTCR structure, the basic characteristic, the main parameter, the application and the trend of development, used the PTC thermistor, LM311, the potentiometer and so on compose a simple temperature alarm device. The experimental result indicated that when contacts by the PTCR probe head the temperature outputs a switch quantity after the circuit switching electric quantity, if the temperature surpasses the predetermined value, this time's switch is opening, may according to the actual need, the switch be possible the positive governing sound, the light alarm apparatus, by form reminder user attentions and so on sound, light. The switch may also connect the execution unit, to was measured that the environment carries on temperature decrease processing, guaranteed that was measured the environment the temperature is in a relative security the temperature section.This temperature alarm device structure is simple, the low cost, the easy place in operation, to have overcome the original artificial temperature measurement, the waste manpower, the physical resource investment shortcoming, enhances the survey the accuracy, timeliness.