PID功能块里的baypass_ena

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这个问题有点没看明白。

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This area is visible if the Bypass Enable option is set in CONTROL_OPTS (typically when the PID block is a slave in a cascade pair). Bypass makes the output value equal to the % SP value, which allows the master loop to drive the output if the transmitter is unavailable. When the block is in MAN or OOS mode, click Bypass to turn Bypass on. Click Normal to turn off Bypass.

这段话有没有看过？

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celanese刘威 发表于 2016-11-5 19:11
看过了！也理解这个bypass的理论意义！但是想请教下：为什么只见到在变频泵的控制应用这个功能呢？
...

In the PID function block, BYPASS is used when the control function block is a slave block in a cascade. If a transmitter failure or some other problem occurs that causes the slave controller to see a Bad input signal, BYPASS can be activated so that the signal coming from the master controller passes through the slave to the field. In this manner, the loop still has some control; however, dynamic performance will suffer because a cascaded loop has effectively been replaced with a single PID.

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celanese刘威 发表于 2016-11-5 19:18
谢谢！在理解理解！

下次别发那个看不清楚的图片了，那图片浪费眼睛。

专业的工程师最近不在，等他来了再确认一下。我对这个程序了解的也不是很深入。