Rockwell Automation LC-Series Linear Motor - Manual (Page 27)

Item Number 814036 - Rev C
Installation 2-21
Motor/Hall Phasing and
Sequence See Figure 2.15 for the standard phase and sequence relationship of the LC
series motors when phased in the specific motor direction. The Trapezoidal
Hall signals are used by a compatible three phase brushless servo drive to
perform electronic commutation. Two types of servo drive Hall-based
commutation techniques are possible, Trapezoidal Hall Mode and Encoder
(Software/Digital) Mode with Trapezoidal Hall start-up. Note: For optimal
commutation and force generation, the selected servo drive must be
compatible with the LC series phasing; and be wired to the motor correctly.
As shown in the phasing diagram:
S1 in phase with C-A Back EMF
S2 in phase with A-B Back EMF
S3 in phase with B-C Back EMF
Phase sequence = S1 leads S2 leads S3. Spacing is 120 degrees.
Figure 2.15 Motor Phasing Diagram
Back EMF Voltage vs. Hall Signals
Phasing direction = coil toward motor power cable or magnet assembly away
from power cable as shown in Figure 2.16.
ATTENTION
!
Incorrect Motor/Hall wiring can cause runaway conditions.
IMPORTANT
Phasing direction = coil toward motor power cable or magnet
assembly away from power cable. Refer to LC-30 Coil and
Cooling Plate Drawing on page 2-3 for specific cable
locations.
0° 60° 120° 180° 240° 300° 360°
S1
S2
S3
Back
EMF
Voltage
Digital
Hall
Signals
A-B
C-A
B-C
W-U = C-A, U-V = A-B, V-W = B-C
(U-S)
(S-T)
(T-U)