Laser DRE

Overview

The Laser DRE is a precision measurement device designed for real-time diameter measurement of rotating objects. It communicates over a USB Serial interface using the Modbus RTU protocol.

Key features include:

• High-speed diameter measurement
• Dual-axis capability
• USB Serial communication
• Modbus RTU protocol support

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Technical Specifications

• Communication Interface: USB Serial
• Protocol: Modbus RTU
• Axes: 2-axis measurement
• Polling Rate: Every 16 ms
• Measurement Rate: 320 measurements per second (manufacturer specification)
• Measurement Type: Diameter measurement | X/Y Axis width

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Operation

Polling

The device polls the diameter every 16 milliseconds, ensuring near real-time data acquisition for precise monitoring.

Measurement

According to the manufacturer, the Laser DRE can measure the diameter 320 times per second, providing high-resolution data for process control and analysis.

Axes

The device is capable of measuring across two axes, allowing for comprehensive profiling of the object’s diameter and shape.

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Communication Protocol

The device uses Modbus RTU over the USB Serial connection. Key points for communication:

• Master/Slave Model: The Laser DRE acts as a Modbus slave device.
• Function Codes: Supports standard Modbus RTU function codes for reading measurements.
• Data Format: Diameter measurements are transmitted in the format specified by the manufacturer (consult the device manual for exact register addresses and scaling).

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Settings

The device includes a small display that allows changing several operational settings:

• Unit: The laser can operate in millimeters (mm) or inches (in). Our software uses millimeters.

• Alarm: The laser can emit an audible alarm if the measured diameter is out of tolerance. ⚠️ Note: The tolerance settings on the laser may differ from the tolerance configured in our software.

• Communication: Several communication parameters can be configured:

  • Set UART: Configure parity (8N1) and baud rate (38400).
  • Set Protocol: Choose the communication protocol. (We use Modbus RTU.)
  • Set Slave Address: The slave address of our laser is 1.

• Calibration: The laser can be calibrated using 4 mm and 8 mm reference rods.