ElmoMC SimplIQ Digital Servo Drives-Bell Command Reference - Manual (Page 178)

UM - Unit Mode
Purpose:
Defines the motion controller drive configuration, as follows:
UM Value Description (Related Commands)
0 Voltage control mode
In this mode, the motor voltage is set directly by the VC software
command. This mode is useful only for very special cases, for motors
with very high resistance and very short mechanical time constants.
Using this mode without extreme care may damage the motor.
1 Torque control mode
In this mode, the motor current command is set directly by the TC
software command or by an analog reference signal. This mode is
useful for torque or force control when the servo drive is used only as
an inner device within an external feedback loop.
2 Speed control mode
In this mode, the motor speed command is set directly by the JV
software jogging command or by an analog reference signal.
3 Micro-stepper mode
In this mode, no commutation is made. The user controls the electrical
field angle using the position commands and the motor current
(holding torque) by the HT[N] command or by an analog signal. All
position mode commands (PA, JV or tabulate motion) are applicable.
This mode cannot be used with DC motors.
4 Dual feedback position control
In this mode, the position controller stabilizes the position of the
auxiliary feedback input. The position controller issues a motor speed
command to an inner speed control loop. The inner speed control loop
derives its speed feedback from the main feedback input. In this case,
auxiliary reference mode (RM=1) is not allowed. The position
command is generated similarly to UM=5, except that the auxiliary
feedback is not available for reference generation.
5 Single loop position control
In this mode, the position controller stabilizes the position of the main
feedback input. The position command is summed by a software
command — point-point (PA), jogging (JV) or tabulated motion (PT,
PVT) — and from an external command. The external command is
derived from the auxiliary feedback reference (FR[N], ET[N], EM[N]).
Table 3-44: UM Values
SimplIQ for Steppers Command Reference Manual Alphabetical Listing
MAN-STECR (Ver. 1.1)
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