General Dynamics 7200 User Manual

Operation
When the antenna is commanded to move on an axis, the current position is
recorded and a timer is set to the value given by Immobile/reversed timeout [ms]
for that axis. When the timer expires, the new current position is compared
against the recorded position. If the antenna does not move in the correct
direction at least the distance given by the Immobile/reversed tolerance [deg], an
error will occur. If no error is detected, the timer is reset and the process repeats
for as long as the antenna is being commanded to move.
If the antenna has not moved the minimum distance, an axis immobile error is
reported and displayed. If the antenna has moved a distance equal to or greater
than the Immobile/reversed tolerance [deg] and in the direction opposite to the
direction commanded by the ACU, an axis reversed error is reported and displayed.
The most common cause of an immobile error is that larger, slower antennas do
not move fast enough to cover the required distance in 2000 ms (2 seconds). To
prevent immobile errors in such systems, the value of the Immobile/reversed
timeout [ms] should be increased, after verifying that the antenna is moving
properly.
The Immobile/reversed tolerance [deg] parameter is not normally changed, except
on small, mobile antennas, where the antenna may move 0.02 degrees due to
wind motion, etc. The value of the parameter may be increased to provide better
immobile and reversed protection to the system. Reversed errors rarely occur once
proper encoder and motor direction have been established.
5.8.6.5.4 Runaway Errors
An axis runaway error is declared by the ACU whenever the antenna is not being
commanded to move, but the encoders report a motion greater than that given by
the Runaway angle parameter. If this error is detected, the drive enable line to the
ACU is opened, which inhibits motion on all axes (the 7200 ACU does not have
individual axis enable lines for each axis).
Executing Clear/correct system faults will clear the error and re-enable the drive
cabinet.
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General Dynamics 7200 Specifications

General

Brand	General Dynamics
Model	7200
Category	Control Systems
Language	English