Relationship between System Type and Log‐Magnitude Curve: For a unity feedback system the static position, velocity and acceleration error constants describe the low‐ frequency behavior of type 0, type 1, and type 2 systems respectively. For a given system, only one of the static error constants is finite and significant. (The larger the value of the finite static error constant, the higher the loop gain is as approaches zero.)
The type of the system determines the slope of the log‐magnitude curve at low frequencies. Thus, information concerning the existence and magnitude of the steady‐state error of a control system to a given input can be determined from the observation of the low‐frequency region of the log‐magnitude curve.
