Unitec DS-205.4, Manual

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DS 205.3 ; DS403.4
A feature of the digital three-phase servo amplifier DS xxx and the brushless d.c. motor
(synchro servomotor, EC motor) drive unit is that it is maintenance-free and has high
control dynamics.
The drive exhibits the known good control characteristics of d.c. drives without the
disadvantages of carbon brush service times and the commutation limit.
The moment of inertia of the rotor is considerably smaller and the maximum power is higher
than for d.c. motors of an identical construction. This results in acceleration values that are
higher up to a factor of 5.
Compared to asynchronous motors with frequency converters the stability, the control
range and the efficiency of the drive are considerably improved.
Since the temperature increase of the motor is only in the stator, the EC motors are always
designed to protection degree IP 65.
The brushless d.c. motor is electrically designed as a synchronous motor with a permanent
magnet rotor and a three-phase stator.
The physical properties correspond to those of the d.c. Motor, i.e. the current is proportional
to the torque and the voltage is proportional to the speed. The speed is controlled stably up
to the maximum current (max. torque). When an overload occurs the speed drops and the
current remains constant.
Rectangular speed/torque characteristic.
The current, the speed and the position are measured exactly. The rotary field frequency is
not a controlled variable, it sets itself automatically.
The motor voltages and currents are sinusoidal. Maximum motor efficiency by
compensating current control.
DS 400 can be used as a torque amplifier, a speed amplifier or a single axis position
amplifier.
The position and speed actual values are generated from the sensor unit (resolver or
incremental encoder). The encoder pulses are emitted from the amplifier for a superposed
SPC/CNC control.
The current, speed and position control loops are easily programmable digital PID
controllers. Programming is at a PC or a programming box.
Communication with superposed controls through BUS systems (standard CAN-BUS,
RS232) or through an analog interface.
Caution:
For DC-BUS fed DC, AC or bl servo amplifiers in the braking mode it is necessary to take
into account the power reverse feed in the DC-BUS. (lifting drives, unwinders, great
flywheel masses)
External regenerative circuit discharge resistor.
Information:
Other products
Classic
Thyristor-Drive 200W up to 800kW
BAMO, BAMOBIL, BAMOCAR Battery-Motor-Controller up to 100kW
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