User Manual V 1-4.XX User guide

13-8 Understanding the Auto-tuning Procedure
Typical values for per unit motor resistance are in the range of 1% to
3% as displayed in Stator Resistnce. The value in Stator Resistnce
increases as the length of wiring runs increase.
Several faults have been included to identify some problems that can
occur in the resistance measuring routine. If the drive trips during the
resistance test, check bits 6 through 10 of Autotune Errors
(parameter 176):
Running the Flux Current Test
Rated motor flux is required to produce rated torque at rated current.
The motor flux test measures the amount of current required to
produce rated motor flux and displays the amount in Flux Current
(parameter 168). The motor accelerates to approximately two-thirds
base speed and then coasts for several seconds. This cycle may repeat
several times. The motor then decelerates to a low speed before
disabling.
If the motor will not accelerate, increase Autotune Torque
(parameter 164) until the motor accelerates. Autotune Speed
(parameter 165) changes the speed to which the motor accelerates.
Important: You must run the transistor diagnostics, phase rotation,
inductance, and resistance tests before running this test.
To run the motor flux test:
1. Set bit 4 in Autotune/Dgn Sel (parameter 173).
2. Enable the drive.
The drive enable light turns off when the test is complete.
file:
Autotune
group:
Autotune Status
If this bit is set: Then:
6
Res- >0 Spd
The motor is not at zero speed. Generally, this bit is set in two cases:
• If the motor rotates during this test, an improper result is likely. Make sure the motor (decoupled from load or process)
is not rotating just before or during the test.
• If the motor is not rotating during this test, then investigate electrical noise creating encoder transitions. Improper
encoder grounding or a noisy encoder power supply could cause noise.
This fault cannot be determined for encoderless applications. You must visually check for this condition on encoderless
systems.
If your motor does rotate during this test, consult the factory.
7
Res-Sign Err
A sign error fault occurs when the average voltage is negative. If you receive a sign error, run the test again because the
value returned is not reliable.
8
Res-0 Cur
If this bit is set, you need to:
1. Set the rated motor current in Nameplate Amps (parameter 4) to the correct value.
2. Run the test again.
3. Consider replacing the control board.
9
Res-SW Err
A software fault is generated when an improper sequence of events has occurred. Consider running the test again.
10
Res-En Drop
The drive enable was lost during the resistance test. Consider running the test again and monitor the drive enable (bit 9
of Drive/Inv Status (parameter 15) and/or the Inv En LED on the main control board).
file:
Autotune
group:
Autotune Setup