Overview

The DA-82 is a current signal output module that operates under RS-485 MODBUS RTU communication. It is used in industrial automation systems where an external master controller sends a command to generate a 4-20mA current output. The module is DIN rail-mountable and provides high accuracy signal conversion.

1. Safety Information (p.3-4)

• Electrical Hazards:
  • Power must be isolated before installation or maintenance.
  • This equipment operates at dangerous voltage levels, requiring extreme caution.
• Electrostatic Discharge (ESD) Precautions:
  • Avoid static electricity discharges.
  • Handle PCBs with care to prevent component damage.
  • DO NOT remove or install PCBs while power is applied.

2. Storage Before Installation (p.5)

• Store the equipment in a dry, sheltered area to prevent environmental damage.
• Inspect all components for physical damage before installation.
• Verify that the equipment is not exposed to moisture or extreme temperatures.

3. Features (p.6)

• Generates a 4-20mA current output based on MODBUS RS-485 serial commands from the master controller.
• Supports multiple device addresses for parallel communication.
• MODBUS RTU protocol compliance, operating as a slave unit.

4. Technical Specifications (p.6)

5. Outline & Indicators (p.7)

• 8 output channels (each with 3 terminals).
• Requires a 24V DC power supply.
• LED Status Indicators:
  • PWR (Power LED): Lit when power is supplied.
  • RXD (Receive LED): Flashes when data is received.
  • FAIL LED: Indicates an incorrect command or current out of range.

6. Installation & Communication Setup (p.8)

• DIP Switch Settings:
  • Each device can be assigned a unique MODBUS slave address.
  • Baud rate selection via DIP switch.
• RS-485 Communication Wiring:
  • A/B terminals are used for data exchange.
  • A 120Ω termination resistor is optional.

7. 4-20mA Signal Output & Power Options (p.9-10)

• Supports both external and internal power options for 4-20mA output.
• Jumper settings (JP1, JP2, JP3, JP4) define power supply mode:
  • External Power Mode (Default): Uses independent power per channel.
  • Internal Power Mode: Uses DA-82’s supply voltage for output generation.
• 4-20mA Interface Connection Examples provided in the manual.

8. MODBUS RTU Command & Data Structure (p.10-11)

• Master Controller Writing Commands:
  • Uses 13-byte command packets for current output control.
• MODBUS Addressing Format:
  • Each channel has a unique address and supports up to 8 channels per device.
• Example MODBUS Commands:

9. Revision History (p.11)

• Version R4 (2025.03.03) – Fourth revision of the technical manual.