CONTREX M-Traverse - Manual (Page 79)

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TUNING
If your system is unstable, or the position error is unacceptable, tuning may stabilize
your system or reduce the position error differences between the setpoint and
feedback. You can achieve a stable system using conservative values in the Tuning
Control parameters, however the position error may be unacceptable. On the other
hand, aggressive values in the Tuning Control parameters may cause the system to
become unstable. The goal is to reduce the position error to the level that you want, yet
maintain the system's stability.
To achieve an acceptable level of position error, increase the Gain (CP-65) parameter
until the system becomes unstable then reduce the CP-65 incrementally until the
system stabilizes. In systems that require greater accuracy, it may be necessary to
adjust the Integral (CP-66) parameter to reduce any remaining position error. In
systems with low inertia, the position error will be reduced more quickly if you enter
higher values in CP-66. An entry that is too high, however, can create instability or
overshoot the setpoint before reaching the correct value. Generally, use lower entries
for CP-66 on systems with a large inertia.
The M-Traverse comes factory pre-loaded with a complete set of default Tuning
parameters. These default settings are suitable for most applications.
The factory defaults for the Follower Tuning Control Parameters are found in Table 3-
24. To modify the default parameters refer to Table 3-25. If you are uncertain how to
enter a Control Parameter, review the
Operations: Keypad section.
Table 3-26 Default Tuning Control Parameters
CP Parameter Name Parameter Value
CP-65 Gain 3000
CP-66 Integral 1