Servosila-Device-Reference-0xA020192

stalled.
This is not the case with "sensorless" motors. If a motor does not have Hall
sensors or an encoder (or the sensors are not yet wired to the controller), the
controller operates the motor in a so-called "sensorless" mode. An issue with
"sensorless" mode is that it only works whenever the motor reaches a certain
speed. Getting a motor to that speed requires the controller to employ a special
technique called "Kickstart" (configured and enabled separately). The
"Kickstart" technique might cause ripples of torque at very low speeds, just like
a gasoline engine. The ripples are not a problem in a wide range of applications
such as pumps, propellers, or electric scooters that do not need to operate at very
low speeds. Other applications warrant a use of "sensored" motors or even better,
motors with encoders. To summarize the point, "sensorless" motors are cheaper
and easy to use, but might face challenges whenever operated at very low speeds.
Motors with Hall sensors ("sensored") have better performance at low speeds,
produce torque at zero speeds, but might cost a bit more, and require extra wiring
as well as extra configuration on the controller side.
Note that even if a brushless motor has built-in Hall sensors, it is absolutely legal
to initially run the motor as a "sensorless" one. The Hall sensors can be wired to
the controller later as a way to improve performance at low or zero speeds of an
already operational drive. In fact, it is recommended to do it that way since it
allows to gradually introduce complexity into the drive's wiring and
configuration.
The controller can also utilize an external encoder (a "Motor Encoder") instead
of Hall sensors when operating a "sensorless" motor. Such an encoder is even
better than Hall sensors, when it comes to performance at low or zero speeds. An
added benefit is that the encoder can be used for Servo Control and Direct Drive
Control functions. The issue is that an encoder is typically much more expensive
than built-in Hall sensors, and might require complicated mechanical installation,
unless the encoder is built into the motor itself. Set this parameter to
"Sensorless" and proceed to configuring the "Motor Encoder" parameter if you
are commissioning a drive with an encoder, but without Hall sensors.
The controller's auto-configuration procedure is capable of determining if the
motor has Hall sensors that are properly wired to the controller. If the sensors are
connected to the controller, but the auto-configuration procedure does not
identify the motor as a "Sensored" one, please check the cabling and connectors
between the controller and the Hall sensors of the motor.
10 Motor Encoder - • 0: No encoder
• 1: Quadrature Encoder
• 2: BISS-C/SSI Encoder
• 3: SPI Encoder
• 4: PWM Encoder
The controller is designed to interface to up to two absolute encoders integrated
UINT16,
0x2000,
0x0A,
rw
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