Rockwell Automation 1398-DDM-xxx ULTRA 100 Series Drives Installation Manual - Manual (Page 265)

Publication 1398-5.2 – PDF 1997
Creating Custom Motor Files D-11
The Hall/Hall type of startup commutation should be used unless the
motor is a special version of an Allen-Bradley motor. The reasons for
this are:
●
The ABS signal is only available on Allen-Bradley motors.
● Hall/Hall commutation means that the location of the Index signal
is unimportant.
If the drive is set up for Hall/Hall startup commutation, the initial
commutation angle is determined by the state of the three Hall
feedback inputs: 001, 010, 011, 100, 101, or 110. When the motor
begins moving, a transition from one Hall state to another (for
example, 001 to 101) identifies a precise commutation angle, and the
measurement is completed. After the final Hall measurement occurs,
the encoder A/B inputs are used to track the commutation angle.
Invert Direction
The invert direction check box may be used as a substitute for
swapping the motor phase leads and Hall feedback signal wires. This
option is valid only if the motor runs backwards from the
Allen-Bradley standard and only if counter-clockwise (CCW) rotation
produces the same motor power and Hall feedback sequencing as
rotating an Allen-Bradley motor clockwise (CW).
The invert direction check box may also be checked for some
Allen-Bradley motors, where the definition of forward is opposite that
of Allen-Bradley (i.e., CCW rather than CW). In such a case, a
software inversion is preferable to the physical swapping of leads,
because the signals look identical when rotated CCW rather than CW.
For custom motors, other than those mentioned above, leave this box
unchecked and swap the motor power and Hall feedback signals to
correct the phasing.
Electrical Parameters
Resistance
The resistance value is the measured phase-to-phase resistance of the
stator winding in Ohms. The resistance is used to set the current
regulator gains, and is critical to current loop performance. The
resistance value can be in the range from 0.0039 to 255.9961
Ω
.
The ratio of motor inductance to motor resistance is defined as the
electrical time constant of the motor. This value should always be
checked to verify that it is in an acceptable range. Electrical time
constants less than ~1mS, and higher than ~50mS, present difficulties
for current regulation and should be avoided.