Galil DMC-2X00 - Manual (Page 16)

General I/O
The DMC-2x00 provides interface circuitry for 8 bi-directional, optoisolated inputs, 8 TTL outputs and
8 analog inputs with 12-Bit ADC (16-Bit optional). The DMC-2x00 also has an additional 64 I/O and
unused auxiliary encoder inputs may also be used as additional inputs (2 inputs / each axis). The
general inputs can also be used as high speed latches for each axis. A high speed encoder compare
output is also provided.
2x80
The DMC-2x50 through DMC-2x80 controller provides an additional 8 optoisolated inputs and 8 TTL
outputs.
System Elements
As shown in Fig. 1.2, the DMC-2x00 is part of a motion control system which includes amplifiers,
motors and encoders. These elements are described below.
Computer DMC-2x00 Controller
Amplifier (Driver)
Power Supply
Encoder Motor
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. (Galil's "Motion Component
Selector" software can help you with motor sizing). Contact Galil at 800-377-6329 if you would like
this product.
The motor may be a step or servo motor and can be brush-type or brushless, rotary or linear. For step
motors, the controller can be configured to control full-step, half-step, or microstep drives. An encoder
is not required when step motors are used.
Amplifier (Driver)
For each axis, the power amplifier converts a +/-10 volt signal from the controller into current to drive
the motor. For stepper motors, the amplifier converts step and direction signals into current. The
amplifier should be sized properly to meet the power requirements of the motor. For brushless motors,
an amplifier that provides electronic commutation is required or the controller must be configured to
provide sinusoidal commutation. The amplifiers may be either pulse-width-modulated (PWM) or
linear. They may also be configured for operation with or without a tachometer. For current
amplifiers, the amplifier gain 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.
For velocity mode amplifiers, 10 volts should run the motor at the maximum speed.
6
•Chapter 1 Overview
DMC-2X00