User`s guide

Identifying Low-Order Transfer Functions (Process M odels)

• Under Poles, select the number of poles, and then select All real or

Underdamped.

Note You need a t least two poles to allow underdamped modes

(complex-conjugate pair).

• Select the Zero check box to include a zero, which is a numerator term

other than a constant, or clear the check box to exclude the zero.

• Select the Delay check b ox to include a delay, or clear the check box

to exclude the delay.

• Select the Integrator check box to include an integrator (self-regu la ting

process),orclearthecheckboxtoexcludetheintegrator.

The Parameter areashowsasmanyactiveparametersasyouincludedin

the model structure.

Note By default, the model Name is set to the acronym that reﬂects the

model structure, as described in “Options for Spe cifying the Process-Model

Structure” on page 3-35.

4 In the Initial Guess area, select Auto-selected to calculate the initial

parameter values for the estimation. The Initial Guess column in the

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