User Manual V 1-4.XX User guide

Understanding the Auto-tuning Procedure 13-5
• All subsequent testing is stopped.
• Some untested devices may be set as open.
Typically, you should fix the hardware faults and run open tests again
to determine if any opens exist.
What Do Open Transistor Faults Indicate?
Open transistor faults could indicate an open anywhere in the control
or power section that turns on a given transistor. You should check the
power transistor gate drive signal from the control board through the
cabling to the opto-isolators continuing through the gate drives and
finally through the cabling to the power transistor. This includes the
power wiring to the motor terminals and the motor. If the bus voltage
is too low, opens could occur; bus voltage should be greater than 85%
of nominal line.
What Happens If Multiple Opens Occur?
If multiple opens occur, several additional faults may be indicated.
For example, if transistor U upper and U lower are open, the test also
indicates that current feedback U phase is open. Because current
cannot run through phase U, the current feedback device cannot be
checked and therefore is listed as a malfunction The type of
installation often determines which parts of the transistor diagnostics
may or may not work. As a result, treat the software only as an aid for
testing the power structure.
What Do I Do If I Get a Software Fault?
If bit 0 of Inverter Dgn 1 is set (1), an improper sequence of events
has occurred. Either the software cannot distinguish what is
occurring, or there is noise in the system. If a fault occurs repeatedly,
the problem may be a fault that the software cannot directly identify
(for example, a voltage breakdown in a snubber). If this is the case,
you need to determine through external measurements if the problem
is real or if there is a noise problem. In cases where a specific test
continually results in nuisance faults, use Trans Dgn Config
(parameter 172) to disable that test.
Running the Phase
Rotation Test
For proper drive operation, you need to have:
• A specific phase sequence of the motor leads (T1 T2 T3, T1 T3
T2 etc.)
• A specific sequence of encoder leads (pulse A leads B, etc.)
These sequences determine which direction the motor shaft rotates
when torque is applied. If the sequence is not set up correctly, the
motor may rotate in the wrong direction or no torque may be
produced.
To run the phase rotation test:
1. Set bit 1 in Autotune/Dgn Sel (parameter 173).
2. Enable the drive.
file:
Autotune
group:
Autotune Setup