7C5.2 Potentiometer Functions - O. Thompson Microflite Ultra 2000 Installation & Adjustment Manual

7c5.2 Potentiometer Functions

PN (Speed Loop Gain) - Sets the gain of the speed feedback loop. The gain should be
adjusted for good regulation and stability of the system.
NMAX (Contract Speed) - Fine adjustment for setting contract speed with the maximum speed
reference input to the control. (This adjustment should be made after selecting the appropriate
tach feedback scaling switch setting of S1.)
ACAL (Armature Feedback Calibration) - The armature feedback calibration adjustment is
used to achieve good stability and response of the machine. It is manually adjusted by
monitoring the armature feedback test point (XY6) and adjusting the armature feedback
potentiometer clockwise for 7.0V at contract speed. This adjustment may be fine tuned for
maximum stability of the system. The response may be too slow if the armature feedback is
too high. This adjustment, as well as stability gain, sets the armature voltage reference for the
tach loss circuit. Setting will vary depending on the load. To adjust, run one car at contract
speed in both directions to determine the voltage difference by subtracting one reading from
the other. One-half of this difference should be subtracted from the baseline of 7.0V.
Example - If difference is .20 volts. Subtract .1 (½ of .20) from 7.0V. Therefore, pot should be
adjusted to 6.9 up.
ACMP (Armature Feedback Compensation) - The armature feedback compensation
increases the effect of the armature feedback. The response of the machine may be too slow
if the ACMP is too high. The ACMP potentiometer should be adjusted to achieve good,
smooth operation. Too much ACMP may also affect running regulation.
IDN (Current Limit Setpoint) - It is set for the amount of field current the control can regulate.
The IDN pot is preset and sealed at the factory. It should not be readjusted. This pot sets the
maximum amount of current output. It is preset for 15 amps. Instability in the system could
result if the current is adjusted too high.
OFFSET - Provide and offset adjustment to prevent the elevator from "creeping" when zero
speed is commanded to the control.
PI (Current Loop Gain) - Normally left about mid range. Provides a means to increase or
decrease the gain of the control loop if the generator field current is unstable.
TFB (Tach Feedback Calibration) - The tach feedback adjustment is used to calibrate the
tach feedback at contract speed for 7.0V. (ATXY5) This signal is used in the tach loss,
direction fault and overspeed circuits as well as for monitoring the actual vs. set speed.
OVS (Overspeed Setpoint) - The overspeed setpoint is used to set the overspeed trip point of
the control from 110% (fully CCW) to 125% (fully CW). The re-level limit will also be affected
by this adjustment from 10% (fully CCW) to 12.5% (fully CW).
7c.5.3 Regulator Test Points
Common test point for all other test points. The black meter lead should
XY3 (COMMON)
always be connected to this test point when referencing other test points
Pattern reference test point. With the red meter lead on this test point,
XY4 (REF IN)
the polarity should be positive when the pattern reference on terminal 5
is positive in respect to terminal 7.
Revision: AA 2.2
Microflite Ultra 2000 - Amicon Regulator
Printed 03 - 15 - 03 7c - 8