User guide

Xenus Plus User Guide Operational Theory
Copley Controls 25
2.6: Input Command Types
The drive can be controlled by a variety of external sources: analog voltage or digital inputs, CAN
network (CANopen), EtherCAT, CoE (CANopen over EtherCAT), MACRO, or over an RS-232
serial connection using ASCII commands. The drive can also function as a stand-alone motion
controller running an internal CVM program or using its internal function generator.
2.6.1: Analog Command Input
Overview
The drive can be driven by an analog voltage signal through the analog command input. The drive
converts the signal to a current, velocity, or position command as appropriate for current, velocity,
or position mode operation, respectively.
The analog input signal is conditioned by the scaling, dead band, and offset settings.
Scaling
The magnitude of the command generated by an input signal is proportional to the input signal
voltage. Scaling controls the input-to-command ratio, allowing the use of an optimal command
range for any given input voltage signal range.
For example, in current mode, with default scaling, +10 Vdc of input generates a command equal
to the drive’s peak current output; +5 Vdc equals half of that.
Scaling could also be useful if, for example, the signal source generates a signal range between 0
and +10 Vdc, but the command range only requires +7.5 Vdc of input. In this case, scaling allows
the drive to equate +7.5 Vdc with the drive’s peak current (in current mode) or maximum velocity
(in velocity mode), increasing the resolution of control.
Dead Band
To protect against unintended response to low-level line noise or interference, the drive can be
programmed with a “dead band” to condition the response to the input signal voltage. The drive
treats anything within the dead band ranges as zero, and subtracts the dead band value from all
other values. For instance, with a dead band of 100 mV, the drive ignores signals between –100
mV and +100 mV, and treats 101 mV as 1 mV, 200 mV as 100 mV, and so on.
Input
Output
0
-100
-200
100
200
0 200-200 -100 100
Dead Band