Exlar EL120, Инструкция по установке и обслуживанию

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Curtiss-Wright | EL120 Rev. G PN60914 10/10/19
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Each amplifier has specific requirements for the feedback on the motor. Not all resolver-
based amplifiers can use the same resolver, resolver alignment, or relative direction of
resolver rotation. Not all encoder-based amplifiers can use the same encoder, encoder
alignment or relative direction of encoder rotation.
Many amplifiers offer software that allows the entering of parameters or the downloading
of "motor data files" that dictate how the feedback must be set up on the motor. Exlar can
provide many of these data files or the proper parameters to enter. Entering motor
parameter data to some amplifiers may require assistance from the amplifier manufacturer.
Feedback Alignment
When Exlar manufactures an EL Series motor, the proper feedback is selected,
mounted, aligned and test run on the amplifier that the customer plans to use, or one that is
known to be equivalent for confirming proper feedback alignment and operation. In any
case where it is determined that the feedback has become misaligned, or an amplifier
change is made requiring the feedback to be aligned differently, it is recommended that
Exlar be contacted and arrangements made to have that procedure performed.
Feedback Wiring
The wiring of the feedback device is critical to the operation of the motor with the
selected amplifier. Wiring the feedback cable incorrectly can cause unstable operation,
incorrect operation or no operation at all. In some cases, improper current limits set in the
amplifier along with improper wiring of the feedback cable can lead to damage of the motor.
Resolvers
A resolver is a non-electronic device that works like a small transformer. When rotated, it
generates 2 sine waves that are out of phase with one another. By decoding these two sine
waves, the amplifier can monitor the direction, revolutions, and speed of rotation of the
motor. Each sine wave typically represents one revolution of the motor, so the amplifier can
also use these signals to know where the motor is within that revolution. By knowing the
motor's position, the amplifier can properly time the supply of current and voltage to the
motor for it to rotate. This process is
commutation. For the amplifier to properly
commutate the motor, it must have a reference, or zero, point from which to track the
motor's rotation. This reference point is critical, and is provided to the amplifier through the
proper alignment of the resolver to the phases of the motor during the actuator assembly.
Encoders
An incremental encoder is an electronic rotary device that transmits a string of electrical
pulses when rotated. Most brushless motors or servo systems that use incremental
encoders use what is called a quadrature encoder. Typical brushless motor encoders use
two data channels, labeled A&B, to provide direction, velocity and position information. The
Channel labeled I or Z has one pulse per revolution and is called the index. The channels
labeled as hall signals or commutation signals are typically labeled S1, S2 & S3; Hall 1, 2 &
3; or Hall A, B & C, depending on the manufacturer's conventions. These signals give the
amplifier the commutation information that it needs to properly rotate the motor.
EL Series Feedback Devices
Standard EL Series motors use either resolvers or encoders as their primary feedback
device. Depending on the amplifier that will be used to operate the actuator, the hookup of
the actuator can vary. Refer to www.exlar.com or contact Exlar for the correct wiring
details.