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在生物教学中,常需用恒温培养箱进行实验材料的培养。在缺乏恒温培养箱的情况下,可把普通电热恒温箱(调温范围45—160℃)进行简单改装,使之既能作恒温干燥箱用,又可作恒温培养箱用(温度范围20—135℃)。改装之前,首先要了解其工作原理。恒温箱的升温是由电阻丝通电加热完成的。当温度升高到规定温度时,箱内的活动接点CB断开,电源切断,电阻丝停止加热。当温度低于规定温度时,活动接点接通,电阻丝开始加热。如此
In biology teaching, it is often necessary to incubate the experimental material with a thermostatic incubator. In the absence of a constant incubator, the ordinary electric incubator (thermostat range 45-160 ℃) for simple modification, both for constant temperature oven, but also for constant temperature incubator (temperature range 20- 135 ° C). Before the conversion, we must first understand its working principle. The temperature is heated by the resistance wire heating completed. When the temperature rises to the specified temperature, the movable contact in the box CB is disconnected, the power is cut off, and the resistance wire stops heating. When the temperature is lower than the specified temperature, the active contact is turned on and the resistance wire starts to heat up. in this way