RS-485总线短路故障检测技术研究

短路故障是RS-485总线的常见故障,其危害较大,容易造成总线控制芯片的损坏。RS-485总线一般通过发送检测报文来判定总线工作是否正常,该类方法的反应较慢,且不能避免接口电路的损坏。本文提出了一种基于电流检测的短路故障检测方法,它可以实时在线检测分支电路的短路故障,从而可立即屏蔽掉故障分支点,避免短路故障进一步损坏系统。

A Study of the RS-485 Serial Bus Short Circuit Failure Detection Technique

Short circuit failure is a common and harmful fault of the RS-485 serial bus,which easily brings great damages to the serial bus controlling chips.Generally,detectable packets are sent to determine whether the RS-485 serial bus works well or not.However,this method responds slowly and can not avoid damaging the relevant interface circuit.A novel detection technique for short circuit failure based on current detection is presented in this paper.It can detect the short circuit failure of the branch circuit on-line,and can shield the branch fault point immediately,which prevents short circuit failure from damaging the systems further.