SM-Resolver User Guide 17
Issue Number: 4 www.controltechniques.com
5.3 Encoder simulation output
The SM-Resolver provides a simulated encoder output with this being configured for a
1024 line quadrature output at default. The source of the output can be selected by
parameter configuration (Pr x.24), as either the resolver itself or the drive main encoder
(EIA485 encoder only).
Table 5.1
5.4 Freeze function
The SM-Resolver has a freeze function, but does not have freeze inputs. The freeze
function can be activated by the SM-Applications or SM-Universal Encoder Plus. When
a freeze signal is provided, the freeze flag (Pr x.39) is set to "ON". When activated, the
non-marker position (Pr x.30) is transferred into the freeze position (Pr x.36).
The freeze flag does not re-set itself. Before carrying out consecutive freeze functions,
the freeze flag must be cleared by the user (Pr x.39 = "OFF") on both the SM-Resolver,
the source of the freeze, and any additional associated Solutions Module..
Simulation based upon the resolver Simulation based upon the drive encoder
Outputs are to EIA485 specification.
Maximum output frequency of 500kHz
Simulated outputs are generated in hardware.
Output format: Quadrature with marker-pulse
(A, B, Z).
Simulated outputs are a buffered version of the
EIA485 inputs of the drive encoder
Scaling of the output is available in order to
reduce the number of lines per revolution (to a
minimum of 128) in defined steps as shown
below:
Scaling is not possible.
A marker pulse will be generated when the
resolver is at the zero position. Both A and B
are low in the zero position.
The marker pulse is a buffered version of the Z
input of the drive encoder.
The width of the marker pulse is determined by
the operating resolution of the resolver, not the
resolution of the encoder simulation output.
The minimum marker pulse width is 300ns
Pr x.25 Ratio
0.0000 to 0.0312 1/32
0.0313 to 0.0625 1/16
0.0626 to 0.1250 1/8
0.1251 to 0.2500 1/4
0.2501 to 0.5000 1/2
0.5001 to 3.0000 1
A 4-pole resolver will give two electrical cycles within one mechanical revolution.
Therefore, a 4-pole resolver cannot provide absolute position (mechanical). Similarly, a
6-pole or 8-pole resolver cannot provide absolute position (mechanical).
It is for this reason that the freeze function does not operate with a resolver that has 4, 6
or 8 poles.
NOTE
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