DERIVATIVE (FB)

FUNCTION_BLOCK DERIVATIVE

Approximates the derivative of a given value in its time course

Four consecutive values are recorded and used in the calculation so that the resulting derivative is as accurate as possible.

Example: Function block in FBD

InOut:

Scope Name Type Comment Input IN REAL Input value TM DWORD Time since last call in msec RESET BOOL TRUE: OUT is set to zero and saved values are set to the current input IN Output OUT REAL Derivative