Servosila-Device-Reference-0xA020192

# Parameter Units Description CANopen
1
counts per
revolution
counts The parameter defines a maximum resolution of the quadrature encoder. The
resolution is defined in quadrature edge counts per revolution. This parameter is
to be taken from the encoder's datasheet.
UINT32,
0x3011,
0x02,
rw
2
encoder bias vs.
electrical
position
counts This parameter needs to be set only if the encoder is used for motor control (a
"Motor Encoder"). Otherwise, keep this parameter as 0.
This parameter specifies a zero offset of the encoder's mechanical installation
vs. an electrical position defined by an order in which the motor's phase lines
are connected to the controller.
The bias can be experimentally determined as the following:
• Positively energize phase "A".
• Negatively energize both phases "B" and "C".
• Let the motor's rotor settle at a position.
• The encoder's reading at that position is the bias.
The procedure needs to be performed after correcting for a possible inversion of
a mechanical installation of the encoder (see "inverted installation" parameter in
this section).
UINT32,
0x3011,
0x03,
rw
3
inverted
installation
(swap A and B
signals)
0 or 1 The direction of the motor's rotation should match the direction of the encoder's
rotation. If that's not the case due to an inverted way the encoder is
mechanically installed, this parameter helps correct the mismatch.
BOOL,
0x3011,
0x04,
rw
4
polarity
inversion
0 or 1 This parameter causes the electronic circuits of the controller to invert A, B, and
I signals of the quadrature encoder before feeding the signals into the software
for analysis.
BOOL,
0x3011,
0x11,
rw
5 UNIT
DISTANCE:
UPPS
0-15 This parameter is used in "UNIT DISTANCE" method of computing speed. The
controller records how much time it takes the encoder to travel a pre-configured
UNIT DISTANCE measured in encoder counts (quadrature edges). By dividing
the UNIT DISTANCE by the recorded time, the controller arrives to an estimate
of speed. This method of computing speed gives reliable results at lower speeds.
However, at higher speeds the recorded time becomes too short thus creating a
quantization issue.
The UNIT DISTANCE is configured as the following silicon-specific way:
UNIT DISTANCE = 2^UPPS
For example, if UPPS is 4, then UNIT DISTANCE is 2^4 = 16 (counts).
Note: increasing UNIT DISTANCE too much introduces latency in speed
measurement since the controller has to wait longer before it can compute
UINT16,
0x3011,
0x13,
rw
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