User guide

44 www.controltechniques.com SM-EZMotion Module User Guide
source parameter. Use this field to enter the desired drive
source parameter (between 00.00 and 21.51).
By default, the SM-EZMotion module configures the
simulated output to work in Quadrature mode. In order to
change the mode, the user will have to change the Drive
Menu Initialization file.
Encoder Simulation Numerator
To add some flexibility to the Simulated Encoder Output
signal, the SM-Universal Encoder Plus module allows the
user to scale the output signal by multiplying the source
with scaling factor. The scaling factor is made up of a
numerator and denominator allowing the user to achieve
nearly any ratio. By default, the Numerator and
Denominator are 1.000 implying that the actual output
value is equal to the Source value. Following is an equation
that defines the use of the Numerator and Denominator
parameters.
Simulated Encoder Output Signal = Simulated Encoder
Source * (Numerator/Denominator)
Encoder Simulation Denominator
To add some flexibility to the Simulated Encoder Output
signal, the SM-Universal Encoder Plus module allows the
user to scale the output signal by multiplying the source
with scaling factor. The scaling factor is made up of a
numerator and denominator allowing the user to achieve
nearly any ratio. By default, the Numerator and
Denominator are 1.000 implying that the actual output
value is equal to the Source value. Following is an equation
that defines the use of the Numerator and Denominator
parameters.
Simulated Encoder Output Signal = Simulated Encoder
Source * (Numerator/Denominator)
7.2.2.4.1.3 SC.SSI
Encoder Setup Parameters
Encoder Supply Voltage
Because of the wide variety of encoders supported by the
Unidrive SP and the SM-Universal Encoder Plus module,
the user must have the ability to define the voltage supplied
to the encoder hardware. The available voltage levels are
5V, 8V, and 15V and are selectable from the list box on the
Encoder view.
N
ote
Be sure not to configure a supply voltage greater
than that supported by the encoder. The Unidrive
SP and SM-Universal Encoder Plus cannot protect
against possible damage to the encoder if the
supply voltage is set too high.
SSI Binary Format Select
This parameter is unique to the SSI encoder format. When
using SSI encoders, the data is transmitted over the SSI
network in one of two different formats. The user needs to
select whether they wish to use the default format of
Graycode, or switch to Binary format. Use this list box to
select the desired format.
Encoder Turns
This parameter determines the maximum number of
revolutions before the Rev Counter register (3.28 or x.04)
rolls over. If using an absolute encoder, this should be set
at the maximum number of turns of the absolute encoder
or lower. The maximum number of turns is defined as
follows:
Maximum # of Turns = 2
N
, where N is the Encoder Turns
parameter
Encoder Comms Resolution
Where encoder communications is used to initially read the
absolute encoder position (SC.Hiper or SC.EnDat), the
comms resolution must be set to the maximum resolution
of the absolute position data.
Equivalent Lines Per Revolution
When sin/cos signals are used, the equivalent number of
encoder lines per revolution must be set up correctly to
give the correct speed and position feedback. The
Equivalent Lines Per Revolution (ELPR) is defined as
follows:
SC.Hiper, SC.EnDat, SC.SSINumber of singe waves per
revolution
For SC.Hiper, SC.EnDat and SC.SSI encoders, the sine
wave signal frequency can be up to 166 kHz, but the
resolution is reduced at higher frequencies. The table
below shows the number of bits of interpolated information
at different frequencies and with different voltage levels at
the drive encoder port. The total resolution in bits per
revolution is the ELPR plus the number of bits of
interpolated information.
If the Enable Auto Encoder Configuration checkbox is
selected, the user does not need to enter this parameter
and the Equivalent Lines Per Rev box will appear dimmed.
Lines Per Rev Divider
The Equivalent Lines Per Revolution parameter is divided
by this value. This can be used when an encoder is used
with a linear motor where the number of counts or sine
waves per pole is not an integer.
Position Feedback Device ELPR
Ab Number of lines per revolution
Fd, Fr Number of lines per revolution /2
Volt / Freq 1,000 5,000 50,000 100,000 150,000
1.2 1111111010
1.0 11 11 10 10 9
0.8 10101010 9
0.6 101010 9 9
0.4 99998