Aerotech BAL LINEAR AMPLIFIER SERIES, Руководство пользователя

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Installation and Operation BA Linear Series User’s Manual
2-14
Aerotech, Inc.
Version 1.5
2.7. Motor Phasing Process
When configuring the BAL amplifier to run a brushless motor, the commutation signal
input connections (labeled HALL A, B, C on connector J6 in velocity or torque command
mode pins 4, 16, and 17) are necessary. Two sequences of 30
°
or 0
°
(default) signal shift
can be used, depending on the setting of jumpers JP4, JP10, and JP12. These sequences
and the generated output motor phase voltages (motor output connections A, B, and C
with respect to a real or pseudo neutral connection) are shown in Figure 2-9 The voltages
generated are made under the conditions of a positive signal placed at +INPUT with
respect to -INPUT at control signal input/output connector J6. A “0” for the given HALL
input indicates zero voltage or logic low, where a “1” indicates five volts or logic high.
If an Aerotech brushless motor is used with the BAL amplifier, motor phase and
HALL connections can be easily determined by referring to the system
interconnection drawings in Figure 2-2, Figure 2-3, and Figure 2-4.
2.7.1. Determining Phase/Hall Sequence
For a motor with an unknown phase/hall sequence, a simple test can be performed on the
motor to determine the proper connections to the BAL amplifier.
Before performing the following steps, ensure that the motor power leads are
completely disconnected from the amplifier.
The tests outlined below do not require that the amplifier be turned on since
Figure 2-7 illustrates the generated output voltage of the amplifier relative to the
input Hall sequences.
The equipment needed for this test is a two-channel oscilloscope and three resistors
(typically 10 Kohm, 1/2 watt) wired in a “Wye” configuration.
Connect the ends of the three resistors to motor terminals A, B, C. Use one channel of the
oscilloscope to monitor motor terminal A with respect to the “Wye” neutral (i.e., the
point where all three resistors are connected together). Turn the shaft of the motor CCW
and note the generated voltage. This voltage represents the “phase A to neutral” CEMF.
With the second oscilloscope probe, determine the Hall switch that is “in phase” with this
voltage. Similarly, phase B and C should be aligned with the other two Hall switches.