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时间继电器测试

2013/11/6 9:20:47点击:

  时间继电器是一种时间控制元件,其具有延时精度高,延时范围宽、使用寿命长、功耗小、输出触点容量大、调整方便和直观;另外还具有外观体积小、重量轻、结构紧凑等优点。从功能种类上分:有通电延时型、接通延时型、断电延时型、短开延时型、间隔延时型、往复延时型(周期通断)、累计定时、多路延时型、星—三角起动型和多功能延时型。而涉及到时间继电器具体所需检验的延时参数:如延时重复误差Er、整定误差Eset、电压波动误差Ev、温度误差Et、综合误差Ec等在具体测试时较烦琐,尤其在上述延时参数Er(重复误差)、Eset(整定误差)、Ev(电压波动误差)又是判断时间继电器延时性能的重要依据,而上述参数在检验人员进行检测时就必须逐台在专用的时间继电器测试台上与高出被测产品一定精度的时间计时仪进行同步类比,将其被测产品设定显示值与其高精度计时仪相比对以计时仪所显示的时间为延时参数,并且还需对每次所测量的参数进行记录,待所测规定次数达到后,然后再根据相应的误差公式对其数据进行验算处理。对其结果与规定的允许误差值比较,最终判定该误差产品某项误差指标是否达到规定要求。

  上述传统的检测手段则对检验测试人员的要求较高,相应的检验强度及人为的数据处理工作量也很大,而在检测和记录中难免会出现误差,从而影响到对被检测的正确判断。基于上述考虑,用单片机和相应外围检测系统将时间继电器延时参数数据进行检测并储存保留,待所确定的检测次数完成后,通过对其存储的记录数据进行 处理,对处理后的延时误差值与被测产品允许的延时误差相比较来判定产品延时误差是否符合要求,并将其最终结果传输到微机中并且打印出来。通过单片机对检测过程中的自动检测,这在检测过程中大大降低了检验人员的工作强度,对产品的检测也更加科学,更加规范,相应的延时误差及延时参数也醒目直观,在很大程度上保证了产品的检测精度。总之,智能化对时间继电器参数的检测有其很强的适用性,它不仅大大简化了相应检测操作,也为检测的准确可靠提供了较好的保证,所以智能化的检测会在时间延时参数检测方面会越来越体现出其优越性。

 典型时间继电器时间参数测试电路

  在典型时间继电器测试电路中,一般常规采用石英计时仪与被检测时间继电器进行延时同步比对。石英计时仪精度可达10-4~10-7h,且检测时间范围可调(可根据被检测产品选择相应的S、min、h计量单位),每次测试后可控制使其自动清零。被检测时间继电器延时显示最小时间为0.01S(10ms),石英计时仪精度可满足其测试精度要求。

  因时间继电器使用范围较广,也从而导致工作电压规格的多档性。如考虑使用模拟式指针仪表可考虑1.5级,并且使AC(DC)电压显示均考虑分档显示其电压值应使其刻度在1/3~2/3处使用,以确保其精度。如DP(数字)面板表可考虑采用表来指示其电压值。另外对ACV考虑其波形失真度不应大于7%,其频率误差不大于50Hz+2%;DCV峰值纹波系数不大于5%。

  以被测产品工作AC220V,延时时间10S,测试AC220V试验电路示于图1(a)。

时间继电器测试(06-100)