STACIS
2100 Piezoelectric Isolation System - Installation & Operation Manual
P/N 96-28765-01
Page 27 of 43
system) using the TMC PC based application
TMC Analyzer
.
See Appendix C for detailed
instructions on running the analyzer software
.
5.3.5
Adjust X/Y/Z Gains - Gain Adjustment
All control gains of the
STACIS
isolation systems have been set at the factory to provide optimal
performance in all typical installations. However, in some installations (installations on weak floors, for
example), it may be necessary to adjust the control gain of one or more axes to improve system stability.
The procedure for adjusting the system’s control gains is as follows.
a. Plug an oscilloscope to the controller’s BNC Output to monitor the system’s signal.
b. Select the axis for which the gain needs to be adjusted.
c. Adjust the gain as appropriate, using
(+)
key to increase (but not above 0 dB) or
(-)
key to decrease.
Note: each click of the key alters the gain by 1 dB
5.3.6 Axis Enable/Disable
This is the menu option for individually activating or deactivating the control servo loop for each active
axis. This menu is a powerful diagnostic tool that can be used to identify sources of system’s instability.
The
BNC output
is automatically set to the axis displayed on the LCD. The standard procedure is to
identify unstable axis is the following:
•
Disable all axes – set each axis as
Disabled
.
•
Enable them by adding (set to
Enabled
) one axis at the time. After each axis is enabled, monitor
the system stability for approximately 15-30 seconds. In this matter, systematically find the axis,
which by
Enabling or Disabling
create or eliminate instability.
To keep the new gains permanently, save them in the controller’s non-volatile (FLASH)
memory (explained later in this section)
•
If the system goes into high-frequency oscillation (making an audible ‘chirp’ sound),
the gain should be reduced until the oscillation is eliminated.
•
If the low-frequency drift of the control signal exceeds +/- 0.5 volts under ‘normal’
circumstances (a quiet room environment, and no storms outside), the gain should
also be reduced until this behavior goes away.
Gains must never be increased above the 0 dB level.
The system is not designed to
handle gains above this level. Too high a gain may result in oscillation and saturation.
Optimal adjustment of the gains requires training and experience. Though the system
cannot be damaged,
always contact TMC prior to adjusting the gains
. The
STACIS
isolation system is designed with two advanced features (Oscillation Control
and Saturation Control) which virtually eliminate the need for end-user gain adjustment.
