The Examples For The External Pid Function Of Plc - Delta VP3000 Series User Manual

7-4 The Examples for the External PID Function of PLC

Use external PID function of PLC and freely designate reference input, the control of gain, positive /
negative feedback, upper / lower bound of output to affect the output result. And it can also connect with
any target in the ladder diagram. In addition, there are eight groups of PID control functions to achieve
special application scenarios by setting integral value.
The description below lists the special D number of the first group, the special D numbers of the
following groups 2–N can be got by the first group's special D number + 20 x (N-1), the maximum of N is
eight.
If the setting value of the special D which relates with PID1 module exceeds the setting range or
transgress the setting principles, then M1264 becomes ON and PID output returns zero. And the
corresponding value of errors will be displayed in D1216 with bit format. Refer to the definition of bit
below:

bit0: the command value exceeds the limiting value

bit1: the feedback value exceeds the limiting value

bit2: the gain value (ratio, integral time, differential time) of the controller exceeds the limiting
value

bit3: the upper / lower bound setting value of output exceeds the limiting value

bit4: the upper / lower bound setting error (the upper bound must always be greater than the
lower bound)

bit5: the integration setting value of the controller exceed the limiting value

bit6: differential controller, feedback filter time exceed the limiting value

bit7: the deadband exceeds the limiting value

bit8: the deadband delay time exceeds the limiting value

bIt9–bit15：Reserve
Chapter 7 Second Development PlatformVP3000
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