Galil Motion Control CDS-3310, User Manual

Page: 12 / 166

4
i
Chapter 1 Overview CDS-3310
System Elements
As shown in Fig. 1.2, the CDS-3310 controller and drive system is part of a motion control system,
which includes motors and encoders. These elements are described below.
Figure 1.2 - Elements of Servo systems
Motor
A motor converts current into torque, which produces motion. Each axis of motion requires a motor
sized properly to move the load at the required speed and acceleration. The Galil "
Motion Component
Selector " software can help with motor sizing. Contact Galil at 800-377-6329 if you would like this
product.
The motor may be a servo motor and can be brush-type or brushless, rotary or linear.
Amplifier (Driver)
The power amplifier converts a +/-10 Volt signal from the controller into current to drive the motor.
The amplifier should be sized properly to meet the power requirements of the motor. The amplifiers is
pulse-width-modulated (PWM). The amplifier gain (AG) should be set such that a 10 Volt command
generates the maximum required current. For example, if the motor peak current is 10A, the amplifier
gain should be 1 A/V.
Encoder
An encoder translates motion into electrical pulses which are fed back into the controller. The CDS-
3310 accepts feedback from either a rotary or linear encoder. Typical encoders provide two channels in
quadrature, known as CHA and CHB. This type of encoder is known as a quadrature encoder.
Quadrature encoders may be either single-ended (CHA and CHB) or differential (CHA,CHA- and
CHB,CHB-). The CDS-3310 decodes either type into quadrature states or four times the number of
cycles. Encoders may also have a third channel (or index) for synchronization.
There is no limit on encoder line density, however, the input frequency to the controller must not
exceed 3,000,000 full encoder cycles/second (12,000,000 quadrature counts/sec). For example, if the
encoder line density is 10000 cycles per inch, the maximum speed is 300 inches/second. If higher
encoder frequency is required, please consult the factory.
The standard voltage level is TTL (zero to five volts), however, voltage levels up to 12 Volts are
acceptable. (If using differential signals, 12 Volts can be input directly to the CDS-3310. Single-
ended 12 Volt signals require a bias voltage input to the complementary inputs).
Computer Controller Amplifier
Power Supply
Motor Encoder
CDS-3310