Aerotech Automation1 iXR3, Hardware Manual

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2.8.3. Sine Wave Encoder (Auxiliary) [-CT4 Option]
The Sine Wave Encoder option provides higher positioning resolution by subdividing the
fundamental output period of the encoder into smaller increments. The amount of subdivision is
specified by the AuxiliaryEncoderMultiplicationFactor parameter. Use Encoder Tuning
[A3200: Feedback Tuning] to adjust the value of the gain, offset, and phase balance controller
parameters to get the best performance. For more information, refer to the
Help file .
High resolution or high-speed encoders can require increased bandwidth for correct operation. Use
the High Speed Mode of the AuxiliaryEncoderMultiplierSetup parameter to enable the high
bandwidth mode. Because this mode increases sensitivity to system noise, use it only if necessary.
You can use a sine wave encoder with the -CT4 multiplier option as an input to the PSO. The -CT4
option generates emulated quadrature signals.
For the highest performance, use twisted pair double-shielded cable with the inner shield connected
to signal common and the outer shield connected to frame ground. Do not join the inner and outer
shields in the cable.
Table 2-40: Sine Wave Encoder Specifications
Specification
Value
Primary Auxiliary
Input Frequency (max) 450 kHz, 2 MHz
Input Amplitude
(1)
0.6 to 1.75 Vpk-pk
Interpolation Factor (max)
-CT1 16,384 N/A
-CT2 65,536 N/A
-CT4 65,536 65,536
-CT2/-CT4 Primary Encoder Channel
Interpolation Latency
800 nsec (analog input to quadrature output)
Input Common Mode 1.5 to 3.5 VDC
(1) Measured as SIN(+) - SIN(-) or COS(+) - COS(-)
Figure 2-41: Sine Wave Encoder Phasing Reference Diagram
2.8.3. Sine Wave Encoder (Auxiliary) [-CT4 Option] iXR3/XR3 Hardware Manual
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