B-4 I Appendix
PID Parameters
Finished
12 You should review your work and make sure your system is not on the verge of
oscillating. If your system oscillates intermittently, you probably have your gains too
aggressive. It is better to be mild in your tuning than over-aggressive.
13 You are now finished tuning your system. Be sure to record your parameters bn,
Er, nt, PBH, EH, nH. The parameters may need to be tweaked if your system or
setpoint changes significantly.
Setting the Security Passcode
The TW-S and TW-P Thermolator provides the ability to protect system parameters from
accidental or unauthorized changes. Access to all user-configurable parameters can be
limited by selecting a three digit passcode between 0 and 500.
While the TW-S and TW-P ships with the factory-default “0” as the passcode, we recom-
mend selecting your own unique passcode to protect your machine setup and application.
To change the security passcode:
1 Stop the TCU or ensure that you are on the home screen by pressing the STOP
button .
2 Enter the user configuration menu by holding the “Function”
button for
ten seconds. Assuming that the existing passcode is at its default “0”, simply
push “Select” .
3 The upper display should now show UP. In the lower display, use the “Up”
or “Down” buttons to select the three-digit passcode from to as
desired.
4 Push “Select” to save the changed parameter. Push “STOP” to
exit.
(Continued)