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固态继电器的发热—松川电器为您介绍

2013/11/30 9:32:37点击:

      固态继电器或模块的发热量主要跟所驱动的负载的实际电流有关,而与其本身的电流等级大小关系不大。
  发热量的计算公式(两种):
  1:单相固态继电器、单相交流调压模块、R系列固体调压器
  发热量=实际负载电流(安培)×1.5瓦/安培
  对三相固态继电器、三相交流调压模块,其实际负载电流应为三相实际负载电流之和。
  2:对于单相全控整流模块
  发热量=实际负载电流(安培)×3.0瓦/安培。
  散热器的作用就是把固态继电器或模块产生的热量散发出去,散热效果不但跟散热器的大小有关,还跟环境温度(季节)、通风条件(自然冷却或强迫冷却及风量大小)以及安装密度等因素均有关。散热效果的参考标准:使固态继电器或模块的底板(与散热器接触面)温度不得超过80℃。因此实际应用中可在散热器安装面靠近固态继电器或模块的边缘处(20mm以内)安装一只75℃的温度开关(带一对常闭触点),把固态继电器或模块的控制信号串入这对常闭触点,这样当检测点温度超过75℃时,常闭触点跳开,切断控制信号,强迫关闭固态继电器或模块的输出,使其得到保护。一般在每相实际电流超过50A、安装密度大、环境温度高的地方,最好采用温度开关保护。
  固态继电器选用散热器除考虑上述因素外,还要考虑固态继电器或模块本身体积与散热器能否相配,以及散热器在机柜中的安装空间。但最终要保证即使在最恶劣情况下固态继电器或模块的底板温度也不得超过80℃。