Setup For Field Weakening - Parker 590+ DRV Product Manual

4-14
Calibration and Start-Up

Setup For Field Weakening

If the motor requires field weakening to achieve top speed, follow these steps.
NOTE
Field weakening requires tachometer generator, or wire-ended or Microtach encoder speed feedback.
1. Verify that the field current calibration is set as described earlier in this chapter. Many field weakened motor list the field current as two values, a
minimum and a maximum, indicating the field weakened range of the motor. Calibrate the motor field for the larger of these two values.
1b. and verify the field is enabled by monitoring parameter SETUP PARAMETERS::FIELD CONTROL::FIELD ENABLE.
2. Set the following parameters as listed below.
SETUP PARAMETERS::FIELD CONTROL::FIELD CTRL MODE = CURRENT CONTROL
SETUP PARAMETERS::FIELD CONTROL::FLD. CURRENT VARS::FLD. WEAK VARS::FLD. WEAK ENABLE = ENABLED
SETUP PARAMETERS::FIELD CONTROL::FLD CURRENT VARS::FLD. WEAK VARS::MAX VOLTS = 100%
NOTE
This sets the switchover point where field weakening begins.
3. Ensure that SETUP PARAMETERS::FIELD CONTROL::FLD CURRENT VARS::FLD WEAK VARS::MIN FLD. CURRENT is set correctly
for the motor to reach top speed. Calculated MIN FLD. CURRENT using the formula:
This sets MIN FLD. CURRENT 10% lower than the field calculated to reach full speed. The minimum and maximum field currents are found on
the motor nameplate label. The 10% cushion should overcome any inaccuracies in the nameplate data.
4. Run the drive up to base speed. Monitor DIAGNOSTICS::TERMINAL VOLTS to verify that the armature voltage is approximately equal to the
MAX VOLTS value set in the previous step.
5. While slowly increasing the speed above base speed, monitor TERMINAL VOLTS. It should remain constant. Monitor the FIELD I FBK
diagnostic and observe it decrease toward the MIN FLD. CURRENT calculated earlier.
Gradually increase to maximum speed, monitoring TERMINAL VOLTS at maximum speed. If the TERMINAL VOLTS increases or the drive
trips on an OVERVOLTS alarm, the MIN FLD. CURRENT setting is too high. Reduce the parameter slightly in order to reach maximum speed.
Do not reduce this parameter below 10% or you risk the motor running away.
When using an analog tachometer make fine adjustments to the speed feedback calibration by adjusting SETUP
PARAMETERS::CALIBRATION::ANALOG TACH CAL.
6. For regenerative, reversing drives, check the maximum reverse speed. Correct any asymmetry in a reversing drive by adjusting SETUP
PARAMETERS::CALIBRATION::ZERO SPD. OFFSET.
7. Stop the drive and SAVE PARAMETERS.
NOTE
If the standard settings don't provide adequate performance, contact Parker SSD Drives Product Support for information on manually
tuning the drive for field weakening.
(Minimum Field Current ÷ Maximum Field Current) × 90%
DC590+ DRV Series DC Digital Drive