Galil DMC-1510, User Manual

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Chapter 1 Overview DMC-1500
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 desired speed and acceleration. Galil's Motion Component
Selector software can help you calculate motor size and drive size requirements. 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.
Amplifier (Driver)
For each axis, 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.
For brushless motors, an amplifier that provides electronic commutation is required. 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.
For stepper motors, the amplifier converts step and direction signals into current.
Encoder or Position Sensor
An encoder translates motion into electrical pulses which are fed back into the controller. The DMC-
1500 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-
,CHB,CHB-). The DMC-1500 decodes either type into quadrature states or four times the number of
cycles. Encoders may also have a third channel (or index) for synchronization.
The DMC-1500 can also interface to encoders with pulse and direction signals.
There is no limit on encoder line density, however, the input frequency to the controller must not
exceed 2,000,000 full encoder cycles/second or 8,000,000 quadrature counts/sec. For example, if the
encoder line density is 10,000 cycles per inch, the maximum speed is 200 inches/second.
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 DMC-1500. Single-
ended 12 Volt signals require a bias voltage input to the complementary inputs.
The DMC-1500 can accept analog feedback instead of an encoder for any axis. Note: the DMC-1580
controller must be modified by the factory to allow for analog feedback on axis H. For more
information see description of analog feedback in Chapter 2 under section entitled "Test the encoder
operation".
To interface with other types of position sensors such as resolvers or absolute encoders, Galil can
customize the controller and command set. Please contact Galil to talk to one of our applications
engineers about your particular system requirements.
Watch Dog Timer
The DMC-1500 provides an internal watch dog timer which checks for proper microprocessor
operation. The timer toggles the Amplifier Enable Output (AEN) which can be used to switch the
amplifiers off in the event of a serious DMC-1500 failure. The AEN output is normally high. During
power-up and if the microprocessor ceases to function properly, the AEN output will go low. The