ABB MicroFlex e190 User Manual page 126

126 Fault tracing
Code Error
4020 Can't fit load model speed data
(_ecCANNOT_FIT_LOAD_MODEL
)
4021 Motor test timed out
(_ecAUTOTUNE_TEST_TIMEOUT
)
4022 Motor travelled too far during test
(_ecAUTOTUNE_TEST_OVERTR
AVEL)
Cause
During the Measure the motor
inertia test, a torque waveform is
applied by the motor and the
motor speed logged. A simple
inertia/damping model is then
fitted numerically to the
resulting torque/speed
characteristic. Error 4020
indicates that the fitting process
failed. A common cause for this
is lack of sufficient information
to fit the load model.
During the Measure the voltage
constant and Measure the motor
inertia tests, current is applied to
the motor to accelerate the
motor and load. Error 4021
indicates that the rotor did not
reach a sufficient speed, or
travel a sufficient distance, within
the duration of the test. Error
4021 can occur if the torque (or
force) generated by the motor is
insufficient to overcome friction
in the load.
During the Measure the voltage
constant and Measure the motor
inertia tests, current is applied to
the motor to accelerate the
motor and load. Once the motor
has reached a sufficient speed,
the direction of applied current is
reversed to bring the rotor to a
halt within specified travel limits.
Error 4022 indicates that the test
was unable to impose these
limits.
What to do
Click Options... in the Autotune tool
and then select the Limits tab.
Increase the value in the Max Travel
box to allow the motor to rotate
further during the test and
consequently log more data. The
model fitting process can also fail for
certain types of load. For example,
loads with high coulomb or static
friction will not conform well to an
inertial load model. Likewise
gravitational loading (i.e. vertical
axes) will cause problems for
autotuning. If the Measure the motor
inertia test continues to fail then the
subsequent Calculate the speed and
position gains test will also fail, as it
requires values for load inertia and
damping. It may be necessary to
manually tune the system using the
Fine-tuning tool's Speed and Position
tabs.
Click Options... in the Autotune tool
and then select the Limits tab.
Increase the value in the Max Torque
box to allow the motor to generate
sufficient torque to overcome
friction.
If the Measure the motor inertia test
continues to fail then the
subsequent Calculate the speed
and position gains test will also fail,
as it requires values for load inertia
and damping. It may be necessary
to manually tune the system using
the Fine-tuning tool's Speed /
Velocity and Position tabs.
Click Options... in the Autotune tool
and then select the Limits tab.
Increase the value in the Max Travel
box to allow the motor to rotate
further during the test. Also, try
reducing the value in the Max Speed
box. If the Measure the motor inertia
test continues to fail then the
subsequent Calculate the speed
and position gains test will also fail,
as it requires values for load inertia
and damping. It may be necessary
to manually tune the system using
the Fine-tuning tool's Speed /
Velocity and Position tabs.