|
|
|
<section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><section><svg viewbox="0 0 1 1"></svg></section></section><section><section powered-by="gulangu"><p><strong>明日复明日，明日何其多。</strong></p></section><section powered-by="gulangu"><p>○</p></section><section powered-by="gulangu"><p><strong>无畏的太阳</strong></p></section><section powered-by="gulangu"><p>○</p></section><section powered-by="gulangu"><p><span>医疗|学习|钻研|电子电路|原理</span><br /></p></section></section><section><section><svg viewbox="0 0 1 1"></svg></section></section></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><p><img src="image/20201019/650ce4aa32dd6d8adad30cfb31871598_1.jpg" /></p></section></section><section powered-by="gulangu"><p><strong>欢迎关注</strong></p></section></section><section><section powered-by="gulangu"><section><p><img src="image/20201019/256e469628ca3f3543b89cd866f093b9_2.png" /></p></section></section><section powered-by="gulangu"><p><strong>好学医电在线</strong></p></section></section></section><section powered-by="gulangu"><p><strong>请留下你指尖的温度</strong></p><p><strong>让太阳拥抱你</strong></p><p><strong>记得这是一个有温度的公众号</strong></p></section></section></section><section powered-by="gulangu"><section><section><section powered-by="gulangu"><section><section><section powered-by="gulangu"><section><br /></section></section></section><section><section powered-by="gulangu"><section><section><br /></section></section></section></section><section><section powered-by="gulangu"><section><p><strong><span> </span></strong></p><p><strong>电热恒温干燥箱</strong></p></section></section></section></section></section><section powered-by="gulangu"><section><section><section powered-by="gulangu"><section><br /></section></section></section></section></section></section><section><section powered-by="gulangu"><section><br /></section></section></section></section></section><section powered-by="gulangu"><p><br /></p></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><br /></section></section></section><section><section powered-by="gulangu"><section><p><strong>故障现象</strong></p></section></section></section></section><section powered-by="gulangu"><p><strong><span> </span></strong></p><p><strong><span> 接通电源，开机设置好参数后，实际温度低于预设温度，设备蜂鸣器不断报警。</span></strong></p></section><section powered-by="gulangu"><section><p><img src="image/20201019/e028d286d52940e0d16e824d13676224_3.jpg" /></p></section></section><section powered-by="gulangu"><p><br /></p></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><br /></section></section></section><section><section powered-by="gulangu"><section><p><strong>分析过程</strong></p></section></section></section></section><section powered-by="gulangu"><p><span><strong>一、<span>原理</span></strong></span></p><p><strong></strong></p><p><strong> </strong></p></section><section powered-by="gulangu"><p><span><strong> 控控板电路原理：市电220VAC经温控板L，N给到变压器输入端，输出2组电压：24VDC跟5VDC。</strong></span></p><p><span><strong> 其中24V电压给到继电器的线圈5和4脚之间，使1和3脚闭合，最后使OUT端输出220VAC。继电器的4和5脚能否得到24VDC取决于三极管是否导通状态。</strong></span></p><p><span><strong> 当温度发生变化，温度传感器阻值随着发生变化，转换成电信号，给到单片机输入端，再由单片机输出信号到运放。与运放里面的基准电压对比后，输出高或低电平到三极管B极，来决定三极管是否导通，EC极是否导通，线圈是否得到24VDC。</strong></span></p></section><section powered-by="gulangu"><section><p><img src="image/20201019/dc2cf61e64141f406038cb3728f80507_4.jpg" /></p></section></section><section powered-by="gulangu"><section><p><img src="image/20201019/e8c02ffab2e814a3ac1011a04fe6227f_5.jpg" /></p></section></section><section powered-by="gulangu"><section><p><img src="image/20201019/5b3a5ece6a8f985fcdbd376d74117b3e_6.jpg" /></p></section></section><section powered-by="gulangu"><p><span><strong> 外部元件连接原理：K1闭合，市电220VAC经接口板N,L，来到温控板的输入端，即板子上的N,L。</strong></span></p><p><span><strong> 当设计温度低于实际温度，温控板OUT端口输出220VAC到固态继电器输入端，其导通，使加热线圈得220VAC，产热。（S加热闭合状态）</strong></span></p><p><span><strong> 当实际温度接近或者等于设计温度，OUT没有输出电压，固态继电器没有输入，不导通，线圈不加热。</strong></span></p></section><section powered-by="gulangu"><section><p><img src="image/20201019/0cf1f5af1473a6d676d9545d505dbfae_7.jpg" /></p></section></section><section powered-by="gulangu"><section><p><img src="image/20201019/71943ed03f8de07cbeb655573b8f1aed_8.jpg" /></p></section></section><section powered-by="gulangu"><section><p><img src="image/20201019/8463b0d75d609459e4491165bb7a0440_9.jpg" /></p></section></section><section powered-by="gulangu"><section><p><img src="image/20201019/d58ca54fe193ca2612fa0f598cc0f5cf_10.jpg" /></p></section></section><section powered-by="gulangu"><p><strong> </strong><strong>二、<span>分析</span></strong></p><p><strong> </strong></p><p><strong> </strong><strong>根据故障现象知道设备可以加热，会报警。排除单片机，加热管，固态继电器。判断以下原因：</strong></p><p><strong> ①传感器偏差。</strong></p><p><strong> ②内部信号传递偏差。</strong></p></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><br /></section></section></section><section><section powered-by="gulangu"><section><p><strong>解决方法</strong></p></section></section></section></section><section powered-by="gulangu"><p><br /></p><p><span><strong> ①传感器偏差：拿温度表检测出来的数值与传感器的数值相同，故排除。</strong></span></p><p><span><strong> ②内部信号传递偏差：示波器检测运放基准信号波形正常，输出波形有干扰。万用表检测其输出脚经过的电容，容值偏低，更换后已经修复。</strong></span></p><p><br /></p></section><section powered-by="gulangu"><section><p><img src="image/20201019/34a664cdf3ebb6847ab2fb23e7df1208_11.jpg" /></p></section></section><section powered-by="gulangu"><p><br /></p></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><p>欢</p></section></section></section><section><section powered-by="gulangu"><section><p>迎</p></section></section></section><section><section powered-by="gulangu"><section><p>关</p></section></section></section><section><section powered-by="gulangu"><section><p>注</p></section></section></section></section><section powered-by="gulangu"><p><br /></p></section><section powered-by="gulangu"><section><section powered-by="gulangu"><section><p><img src="image/20201019/650ce4aa32dd6d8adad30cfb31871598_1.jpg" /></p></section></section></section><section><section powered-by="gulangu"><section><section><br /></section></section></section></section><section><section powered-by="gulangu"><p>好学医电在线</p><p>和他的朋友们</p></section></section></section><section powered-by="gulangu"><section><section><svg viewbox="0 0 1 1"></svg></section></section><section><section><svg viewbox="0 0 1 1"></svg></section></section></section></section> |
|
发表于 2020-10-19 12:45:27