第1个回答 2010-10-12
Temperature control circuit in industrial and agricultural production is widely used in food, such as in the grain warehouse storage warehouse keeping the temperature inside the granary, is kept safe food, this article discusses the important factors of structure, basic characteristics PTCR, main parameters, application and development trend, using the PTC thermistors, relays, LM311 components, such as a simple temperature alarm device.
Experimental results show that, when PTCR probe by the contact with the power output circuit temperature switches, if temperatures exceed predetermined value, namely the switch can open, according to actual needs, switch can directly control sound, light, sound and light alarm in such form remind users note. Switches also can connect to the execution unit, to be measured cooling treatment, environment to ensure the environmental temperature measured by in a relatively safe temperature period.
This circuit is simple in structure, low cost, easy to put into production, overcome the original artificial temperature measurement, the waste of manpower and material resources, increase input, timeliness accuracy of measurement.