Specifications

20 Gear Drive, Plymouth Ind. Park, Terryville, CT 06786
Tel: [phone] Fax: [phone] http://www.amci.com
5
CHAPTER 1
INTRODUCTION TO THE SD17063
Stepper Motor Systems
When you must control rotational position or velocity, stepper motors have several advantages over servo
control systems. The first is cost. Opposed to ‘closed loop’ servo systems that require position feedback to the
drive, stepper systems operate ‘open loop’, accurately controlling position and velocity without feedback.
Eliminating the feedback loop can result in a great cost savings. The stepper motor itself is also tough, easy
to install, and offers high output torque for its size.
As shown in figure 1.1, there are three basic components to a stepper system.
Figure 1.1 Block Diagram of a Stepper System
h The Indexer –
The indexer, sometimes called the controller, generates directional pulses that control the
position, velocity, and rotational direction of the stepper motor. Indexers can take on many forms, from
a fully programmable card for a programmable logic controller or PC, to a ‘black box’ that runs a fixed
profile whenever an operator presses a button.
h The Drive –
The drive converts the directional pulses from the indexer into the current waveforms
needed to drive the stepper motor. The SD17063 accepts differential signals from the indexer and out-
puts 170Vdc digitized waveforms to the motor with a maximum current of 6.3Arms. The SD17063 also
has fault diagnostics that warn you of problems with the motor connections or directional pulses from
the indexer. The SD17063’s fault output is typically fed back to the indexer.
h The Motor –
Stepper motors are available in many different sizes to met specific torque requirements.
AMCI offers motors that range in size from NEMA 23 to NEMA 42.
A position feedback device, such as an optical encoder or resolver, can be added to the system if desired. The
feedback is between the motor and the indexer, and therefore its specification and installation is not covered
in this manual.
The Rev. B drive makes a few minor improvements to the Rev. A drive and it retains the new features
and switch setting that were not available on the older, non-revised SD17063 drives. Therefore, this
manual can be used with the SD17063 Rev. A drives with the exceptions noted below. This manual
cannot be used with the older, non-revised SD17063 drives. The easiest way to determine if you have
a revised or non-revised drive is by the power connector. The new SD17063 Rev. A and B drives have
a green, three terminal, Phoenix Contact connector while the older SD17063 drive has an IEC power
connector.
DRIVE
(SD17063)
INDEXER
Step Pulses
Fault
Diagnostics
Motor
Currents
MOTOR
Position Feedback
(optional)