Aerotech Automation1 iXR3, Hardware Manual

Page: 47 / 112

2.3.1.3. Sine Wave Encoder (Primary) [-CT1/-CT2/-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 PrimaryEncoderMultiplicationFactor [A3200: EncoderMultiplicationFactor]
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 PrimaryEncoderMultiplierSetup [A3200: EncoderMultiplierSetup]
parameter to enable the high bandwidth mode. Because this mode increases sensitivity to system
noise, use it only if necessary.
The iXR3/XR3 with the -CT2 and -CT4 options can generate emulated encoder signals. These signals
can be output on the AUX ENCODER connector, the HSOUT (High-Speed Output) connector, or used
internally by the PSO. Refer to the EncoderDivider and PrimaryEmulatedQuadratureDivider
[A3200: EmulatedQuadratureDivider] parameters and the encoder output functions [A3200:
ENCODER OUT command] in the Help file for more information.
You cannot use a sine wave encoder with the -CT1 multiplier option as an input to the PSO. The -CT1
option does not generate 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 2-12: 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 2-16: Sine Wave Encoder Phasing Reference Diagram
iXR3/XR3 Hardware
Manual 2.3.1.3. Sine Wave Encoder (Primary) [-CT1/-CT2/-CT4
Option]
www.aerotech.com 47