Servosila-Device-Reference-0xA020192

1
physical sensor for
logical sensor 0
0/1/2 If phase "A" is positively energized, and phases "B" and "C" are negatively
energized, this logical sensor reads as "1", while others read as "0".
UINT16,
0x3004,
0x06,
rw
2
physical sensor for
logical sensor 1
0/1/2 If phase "B" is positively energized, and phases "A" and "C" are negatively
energized, this logical sensor reads as "1", while others read as "0".
UINT16,
0x3004,
0x07,
rw
3
physical sensor for
logical sensor 2
0/1/2 If phase "C" is positively energized, and phases "A" and "B" are negatively
energized, this logical sensor reads as "1", while others read as "0".
UINT16,
0x3004,
0x08,
rw
4
Hall signals inverted 0 or 1 This parameter instructs the controller to invert readings of all Hall sensors
before mapping them to logical sensors.
BOOL,
0x3004,
0x05,
rw
Configuration - Peripheral: Quadrature Encoder
This section needs to be configured only if either "Motor Encoder" or "Servo Encoder" parameter in the "Datasheet"
section is set to "Quadrature Encoder". Otherwise, leave this section unchanged. The controller comes with dedicated
hardware, a silicon peripheral, for interfacing quadrature encoders. The peripheral has peculiarities of configuration that
are addressed in this section.
A challenge with absolute quadrature encoders is that they need to use an INDEX signal to search for a zero position
each time the drive is powered up. The controller uses the "Kickstart" procedure to initially rotate such a motor until its
quadrature encoder stumbles up the INDEX signal. The controller then switches to Field Oriented Control (FOC) or
Direct Drive Control until it gets powered off again. The search is commenced upon receiving the first motion
command from a parent control system. The direction of search is derived from the received command.
Note that quadrature encoders allow the controller to measure not just shaft position, but also speed. There are two
distinct methods of how the controller computes the speed:
1. Method #1 "UNIT DISTANCE": The controller records how much time it takes the quadrature encoder's disk 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 the first estimate of speed. The parameter
UNIT DISTANCE is configured in this section. However, at higher speeds the recorded time becomes too short
thus creating a quantization issue.
2. Method #2 "UNIT TIME": The controller records a distance (measured in encoder counts) that the encoder
travels in a UNIT TIME period. By dividing the recorded distance by the UNIT TIME, the controller arrives to
the second estimate of speed. The parameter UNIT TIME is configured in this section. However, at lower
speeds the number of edges counted within the UNIT TIME could be too small thus creating a quantization
issue.
3. Since Method #1 gives reliable estimates at lower speeds, while Method #2 gives reliable estimates at higher
speeds, the controller chooses one estimate or the other by comparing the estimates to a SPEED SELECTION
THRESHOLD configured in this section.
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