Operator-initiated target changes in a SmartStep application 智能向导应用中操作员启动目标发生变化

在TEST,TEST NO-PULSE或SUSPEND模式时测试应用将履行所有的操作员启动目标变化。操作员可以修改STMVTRG的值（最多修改STMVMAXSTEP），并且动作将在下一周期得到执行。目标更改的动作计划不会违反最小或最大移动准则（STMVMAXU，STMVMAXD，STMVMINU，STMVMIND）。没有中高频脉冲被叠加到目标动作计划中。如果目标请求值比STMVMAXSTEP大，动作将被拒绝，并且将生成消息。
正在经历目标变化的MV将显示STEPPING状态直到其达到控制目标，然后它会回到动作开始前的状态。如果操作员决定移动一个当前正处于STEPPING状态的MV，目标动作计划将会取代测试动作计划，但步骤持续时间计数将被单独留下。如果该MV正在执行第一个大阶跃动作，在STMVDUR结束时其依旧将计算它的第二大阶跃动作。如果不期望这种行为，操作员可以关闭测试服务开关来强制测试移动到另一个MV。如果操作员在测试时域接近尾声时使目标移动，并且引擎将花去几个周期全面落实动作，引擎将首先完成目标动作，然后转到下一个MV。
操作员启动变化在执行时将不考虑动作是否会推动过程至CORRECTING模式。该功能应该被用于主动反应干扰或转移工厂至一新工作点。这一功能不应该被用来强制工厂在限制范围内运行，将MV保持在传统工作点，或者其它可能限制智能向导测试应用有效性的原因。通常情况下，其他整定或设计变化就可以解决这些问题。鉴于该功能可能将过程推动到CORRECTING模式，应当谨慎使用。操作员培训应明确界定适当时候进行目标变更。

也可以看看
智能向导应用下的CORRECTING模式
测试信号

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附原文：
The tester application will honor all operator-initiated target changes when in TEST, TEST NO-PULSE, or SUSPEND modes. The operator can change the value of STMVTRG by as much as STMVMAXSTEP, and the move will be implemented at the next cycle. The move plan for the target change will not violate minimum or maximum movement criteria (STMVMAXU, STMVMAXD, STMVMINU, STMVMIND). No high or medium frequency pulses are superimposed onto a target move plan. If the target request is larger than STMVMAXSTEP, the move will be rejected, and a message will be generated.
The MV undergoing the target change will show STEPPING until it reaches its target, and then it will return to the state it had before the move was initiated. If the operator decides to move a currently stepping MV, the target move plan will replace the test move plan, but the step duration counter will be left alone. If the MV is executing its first large step move, it will still compute its second large step move at the end of STMVDUR. If this behavior is not desired, the operator may turn off the test service switch to force the tester to move to another MV. If the operator makes a target move at the very end of the test horizon, and the engine is going to take several cycles to fully implement the move, the engine will finish the target move first and then move on to the next MV.
Operator-initiated changes are implemented without regard to whether the move will push the process into CORRECTING mode. This feature should be used to react proactively to disturbances or to shift the plant to a new operating point. This feature should not be used to force the plant to run within constraints, keep MVs at traditional operating points, or for other reasons that might limit the effectiveness of the SmartStep tester application. Frequently, other tuning or design changes can address those problems. Because this feature can push the process into CORRECTING mode, it should be used sparingly. Operator training should clearly define appropriate times to make target changes.
See Also
CORRECTING mode in a SmartStep application
Test signal

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2015.10.31