Creating Custom Motor Files
B-7
Installation Manual for Models ODM-005, ODM-005i, ODM-010, ODM-010i, ODM-020 and ODM-020i
Feedback Parameters
Linecount
The encoder linecount, or size, specifies the number of encoder lines per mechanical revolution of the
motor, and is required in units of lines/mechanical revolution. The linecount value can be in the range
from 100 to 15000 lines/rev.
Note that the linecount value is in units of lines/rev, rather than counts/rev. The number of lines/rev will
be 1/4th of the number of counts/rev.
Index Offset
The index offset specifies the offset of the encoder index signal in some special motors, and is required
in units of electrical degrees. If the startup commutation type specifies that the index be used for the final
commutation angle measurement, then the drive uses the index offset to determine the commutation angle
when the index is first located (the rising edge). The index offset value can be in the range from 0 to 359
degrees.
For custom motor files, this parameter is not required. Set it to 0, since only the Hall signals are needed
for most custom motor files.
Figure B.4(a) shows the 0
o
index location, and Figure B.4(b) shows an example of a 30
o
index offset.
Hall Offset
The Hall offset specifies the offset of the Hall feedback signals relative to the Thomson Industries standard.
The drive uses the Hall offset to determine the commutation angle at startup. Hall offset is specified as a
value in the range from 0 to 359 electrical degrees.
The Hall signals, as well as the line-to-line back-EMF voltages, must sequence according to the Thomson
Industries standard (refer to Figure B.2 and the “Motor Phasing” on page B-2). The Hall offset value is
the value the drive uses to correct for Hall signals that are shifted from the line-to-line back-EMF.
Figure B.5(a) shows the Thomson Industries standard for orientation of the Hall signals to the line-to-
line back-
EMF voltages. Figure B.5(b) shows an example of a 60
o
Hall offset from the standard location.
Intro
Intro
Intro
(a) Location (0
o
Offset)
(b) Index Location (30
o
Offset)
F
IGURE
B.4
Index Offsets
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