Rockwell Automation 1391 USER MNL/DIGITAL AC SERVO DR - Manual (Page 7)

Chapter 1
Introduction
1-8
Options/Modifications The 1391-DES contains most functions needed in a servo system.
The following are selectable at the user’s option:
•
Contactor Auxiliary Switch
Two N.O. (normally open) contacts are mounted on the main power
contactor and wired to the power terminal block. These contacts can be
used in a motor brake control circuit or as an indicator that the contactor
has closed.
•
Current or Torque Amplifier Operation
When the velocity loop is being closed as part of the position control
system, the drive can be configured to operate as a current or torque
amplifier by selection on the programming panel.
•
External Shunt Regulator Resistor
On 15 and 22.5A drives an internal power resistor that is part of the DC
bus voltage shunt regulator can dissipate 162 watts continuous power.
Some applications such as an overhauling load have excessive
regenerative energy to dissipate. For these applications, an external
shunt regulator resistor rated at 386 watts continuous can be supplied for
user mounting on 22.5A drives. This is selectable by removing the
jumper on TB5 and using an external resistor. The shunt has integral
fusing accessible from the outside of 15 and 22.5A drives. The 45A
drive has an externally mounted resistor and fuse.
Important: An external shunt regulator resistor is included as standard
equipment on 45A units. An additional unit is not required.
•
Tach Output
A voltage equal to 1.2V DC/1000 RPM is available at TB2.
•
Torque or Current Monitor
A voltage equal to 3.0V DC=100% scaled current is available at TB2.
•
Anti-Backlash
Anti-backlash control can be implemented with several software
parameters and an additional instruction manual. Contact your local
Allen-Bradley Sales Office for details.
•
Linear Accel/Decel
Linear accel/decel can be set using the CR-APG-001 Control Module.
This module provides a manually generated trapezoidal velocity profile
for up to four preset speeds.
Important: The 1391-DES contains one accel/decel rate which can be
used if accel/decel times will be the same.
Drive Layout Figure 1.1 provides an exterior view of the 1391-DES AC Servo Drive,
showing accessibility of various components.