triconex 3704E 隔离模拟输入模块 该失效的一支就能被其它两支所补偿

3704E   隔离模拟输入模块

容错是TRICON系统的为重要的能力，它是指对瞬态的和稳态的出错情况的探查发现的能力以及采取适当的相应的在线措施的能力。具有容错能力时，控制器及其控制的过程的安全性得以增强，利用率得以提高。TRICON通过三重组合式冗余结构(TMR)而给出其容错能力。此系统由三个完全相同的系统支路组成(电源模件除外,该模件是双重冗余的)。每个系统支路独立地执行控制程序，并与其它两个支路并行工作。硬件表决机制则对所有来自区域场的数字式输入和输出进行考核和验定。模拟输入则经受中值选择处理过程。因为每一个支路都是和其它两个隔离的， 任一支路内的任何- 个单点失效都不会传递给其它两支。如果在一支内有硬件故障发生, 该失效的一支就能被其它两支所补偿。所以修理工作，包括拆卸和更换失效的支路内的失效模件都可以在TRICON在线情况下进行，不使过程中断。系统能自行重新配置而进行充分的TMR运作。对于各个支路、各模件和各功能电路的广泛的诊断工作能够及时地探查到运行中的故障,并用指示器或警报作出报告。诊断还可以把有关故障的信息存储在系统变量内。在发现有故障时,操作者可以利用诊断信息以修改控制动作,或者指导其维护过程。从用户的观点看,使用是简单的，因为此三重系统工作起来和一个控制系统一样。用户连接感应器和作动器于单一的接线端 上,并且用-组应用逻辑为TRICON编程。其余的事都由TRICON自行经管。

Fault tolerance is the most important capability of a TRICON system, which refers to the ability to detect transient and steady-state error situations and take appropriate online measures. When equipped with fault tolerance, the safety of the controller and its controlled processes is enhanced, and the utilization rate is improved. TRICON provides its fault tolerance capability through the Triple Modular Redundant Structure (TMR). This system consists of three identical system branches (except for the power module, which is double redundant). Each system branch independently executes control programs and works in parallel with the other two branches. The hardware voting mechanism evaluates and verifies all digital inputs and outputs from the regional field. The analog input undergoes the median selection process. Because each branch is isolated from the other two, any single point of failure within either branch will not be transmitted to the other two branches. If a hardware failure occurs within one branch, the failed branch can be compensated by the other two branches. So repair work, including dismantling and replacing failed modules in the failed branch, can be carried out online with TRICON without interrupting the process. The system can reconfigure itself for full TMR operation. Extensive diagnostic work on various branches, modules, and functional circuits can detect faults in operation in a timely manner and report them using indicators or alarms. Diagnosis can also store information about faults in system variables. When faults are discovered, operators can use diagnostic information to modify control actions or guide their maintenance process. From the user's perspective, usage is simple because this triple system works like a control system. Users connect sensors and actuators on a single terminal and program TRICON using a set of application logic. The rest is handled by TRICON himself.