User guide

Configuring an Application www.controltechniques.com 69
This is a simple tool that allows the user to set the analog
input to full scale, and then easily read the value without
requiring additional calibration. The button appears dim
except when online with the SM-EZMotion module.
Minimum Value
In order to scale the raw analog input value into the proper
scale and units for the selected Module Variable, the user
must define the maximum scale value and the minimum
scale value. The SM-EZMotion module then uses linear
interpolation to scale the analog input and populate the
specified Module Variable.
The Minimum Value is the value that the Module Variable
will be set to when the Analog Input reaches the specified
Minimum Input value.
Minimum Input
This defines the Minimum Input value in % that will yield the
corresponding Minimum Value for the selected Module
Variable. The Analog Input is not limited to this value, but
this is used as a point on the “curve” for the linear
interpolation equation.
Set Minimum Input
The Set Minimum Input is a button that, when pressed,
reads the current value of the analog input and stores that
value in the Minimum Input text box. This is a simple tool
that allows the user to set the analog input to minimum
scale, and then easily read the value without requiring
additional calibration. The button appears dim except when
online with the SM-EZMotion module.
Example:
If the Minimum Value is set to -5000, and the Minimum
Input is set to 0%. This means that when the Analog Input
reaches 0% of scale, the value of the selected Module
Variable will be equal to -5000.
Raw Value
The Raw Value is a read-only parameter that while online
with the SM-EZMotion module will show the user the
current value of the analog input in units of % of maximum
scale. The range of this parameter is always 0 to 100%
regardless of the Maximum Input and Minimum Input
values previously configured.
Analog Input - Channel 2
The second analog input on the Unidrive SP is a lower
resolution (10-bit) input. All setup parameters for Analog
Input 2 are the same as Analog Input 1 other than the Input
Mode parameter.
Following is a description of the Input Mode parameter. For
information on other parameters, please see Analog Input
– Channel 1 above.
Input Mode
Analog Input 2 on the Unidrive SP is capable of operating
in multiple different modes so that it can work with different
Analog circuits. The three different types of analog circuits
supported by the Unidrive SP are as follows:
1. 0 – 20 mA Mode – If this mode is selected, the
Drive Analog Input will accept an input value
between 0 and 20 mA. 0 mA corresponds to
minimum scale (or 0%), and 20 mA
corresponds to full scale (or 100%).
2. 4 – 20 mA Mode – If this mode is selected, the
Drive Analog Input will accept an input value
between 4 and 20 mA. 4 mA corresponds to
minimum scale (or 0%), and 20 mA
corresponds to full scale (or 100%).
3. Voltage Mode – If this mode is selected, the
Drive Analog Input will accept an input value
from 0V to 10V. 0V corresponds to minimum
scale (or 0%), and 10V corresponds to full
scale (or 100%).
7.4.5 Analog Outputs
Figure 98: Analog Outputs View
The Unidrive SP has two Analog Output channels that can
be used for a wide variety of applications. The Analog
Outputs can be referred to as Analog Output 1 and Analog
Output 2. Following are descriptions of each of the setup
parameters for each Analog Output.
For more information on the Analog Outputs that is not
covered in this manual, please refer to the Unidrive SP
User Guide and/or the Unidrive SP Advanced User Guide.
Analog Output – Channel 1
Enable Channel
By default, the analog output channel is not enabled
meaning that the SM-EZMotion module is not sending a
value to the analog circuit. If the Enable channel checkbox
is clear (disabled), the configuration parameters for the
analog output appear dim and are unavailable. To enable
the output, simply select the Enable Channel checkbox,
and the configuration parameters will become available for