this voltage may need to be increased and for systems with very small motors, this value should be decreased.

For example, BZ -2

will drive the X axis to zero, using a 2V signal. The controller will then leave the motor enabled. For systems that have external forces working against the motor, such as gravity, the BZ argument must provide a torque 10x the external force. If the torque is not sufficient, the commutation zero may not be accurate.

If Hall Sensors are Available:

The estimated value of the commutation phase is good to within 30°. This estimate can be used to drive the motor but a more accurate estimate is needed for efficient motor operation. There are 3 possible methods for commutation phase initialization:

Method 1. Use the BZ command as described above.

Method 2. Drive the motor close to commutation phase of zero and then use BZ command. This method decreases the amount of system jerk by moving the motor close to zero commutation phase before executing the BZ command. The controller makes an estimate for the number of encoder counts between the current position and the position of zero commutation phase. This value is stored in the operand _BZx. Using this operand the controller can be commanded to move the motor. The BZ command is then issued as described above. For example, to initialize the X axis motor upon power or reset, the following commands may be given:

SHX

;Enable X axis motor

PRX=-1*(_BZX)

;Move X motor close to zero commutation phase

BGX

;Begin motion on X axis

AMX

;Wait for motion to complete on X axis

BZX=-1

;Drive motor to commutation phase zero and leave

 

;motor on

Method 3. Use the command, BC. This command uses the hall transitions to determine the commutation phase. Ideally, the hall sensor transitions will be separated by exactly 60° and any deviation from 60° will affect the accuracy of this method. If the hall sensors are accurate, this method is recommended. The BC command monitors the hall sensors during a move and monitors the Hall sensors for a transition point. When that occurs, the controller computes the commutation phase and sets it. For example, to initialize the X axis motor upon power or reset, the following commands may be given:

SHX

;Enable X axis motor

BCX

;Enable the brushless calibration command

PRX=50000

;Command a relative position movement on X axis

BGX

;Begin motion on X axis. When the hall sensors

 

detect a phase transition, the commutation phase is re-set.

Step 8C. Connect Step Motors

In Stepper Motor operation, the pulse output signal has a 50% duty cycle. Step motors operate open loop and do not require encoder feedback. When a stepper is used, the auxiliary encoder for the corresponding axis is unavailable

DMC-1700/1800

Chapter 2 Getting Started • 33

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Galil DMC-1700, DMC-1800 user manual Connect Step Motors, Amx

DMC-1800, DMC-1700 specifications

The Galil DMC-1700 and DMC-1800 are advanced motion controllers widely recognized for their high performance and versatility in the automation and robotics industries. These controllers are designed to meet the demands of complex motion control applications, providing users with enhanced features and innovative technologies that optimize motion precision and efficiency.

One of the main features of the Galil DMC-1700 is its ability to handle up to 8 axes of motion control. This capability makes it suitable for a range of applications, from simple point-to-point movements to intricate trajectories in multi-axis systems. In contrast, the DMC-1800 extends this functionality, supporting up to 64 axes, making it ideal for large-scale automation environments.

Both models leverage Galil's powerful programming interface, which simplifies the development of motion control applications. The DMC-1700 and DMC-1800 controllers utilize a high-level programming language that supports advanced motion commands, including linear interpolation, circular interpolation, and complex motion profiles. This feature allows users to implement sophisticated motion sequences seamlessly.

In terms of connectivity, the Galil DMC series offers multiple communication options, including Ethernet, RS-232, and CAN bus, ensuring compatibility with various hardware and enabling easy integration into existing systems. The controllers also come equipped with digital and analog I/O ports, providing flexibility for sensor feedback and actuator control.

The advanced technology incorporated into both the DMC-1700 and DMC-1800 includes on-board PID control, which ensures precise motion control through closed-loop feedback. This results in improved stability and accuracy, particularly in high-speed applications. Additionally, the controllers offer extensive diagnostics and monitoring capabilities, allowing for real-time performance analysis and troubleshooting.

Another notable characteristic of these motion controllers is their compact design, which offers space-saving advantages while maintaining high processing power. Their robust construction and ability to operate in challenging environments make them suitable for a wide range of industrial applications, from CNC machining to assembly lines.

In conclusion, the Galil DMC-1700 and DMC-1800 motion controllers stand out due to their high-performance capabilities, advanced programming features, and flexibility in connectivity. With their ability to handle complex motion control tasks efficiently, these controllers are invaluable tools for engineers and manufacturers looking to enhance their automation processes. By integrating Galil's innovative motion control technology, industries can achieve greater precision, speed, and reliability in their operational workflows.