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KOYO D4-RSDC
Product Name: DirectLOGIC DL405 Serial Remote I/O Slave Module
Product Introduction
The KOYO D4-RSDC is a remote I/O communication module for the DirectLOGIC DL405 PLC system. It connects remote DL405 I/O bases to a local master controller using serial communication, reducing long-distance field wiring.
Detailed content
Technical Specifications
Brand: KOYO / AutomationDirect
Model: D4-RSDC
Series: DirectLOGIC DL405
Module Type: Serial remote I/O slave
Communication Interface: RS-485 twisted-pair
Maximum Baud Rate: 38.4 kbps
Power Supply: 24 VDC nominal
Daisy-Chain Capacity: Up to seven remote bases per remote master
Maximum Distance: Up to 1.2 km, depending on baud rate and cable conditions
Mounting: DL405 base or DIN-rail-compatible rack mounting
Operating Temperature: 0–55 °C, per one available specification
Enclosure Rating: IP20; intended for installation inside a control cabinet
Functional Features
Remote I/O Expansion: Links remote DL405 bases to a central PLC master.
Serial Communication: Uses RS-485 differential signaling for industrial environments.
Multi-Drop Support: Allows several remote bases to share one communication link.
Wiring Reduction: Concentrates remote field I/O instead of running individual long cables back to the main cabinet.
System Diagnostics: Provides communication and module status through the DL405 system.
Application Scenarios
Distributed machinery: Remote panels separated from the main control cabinet
Conveyor and material handling systems: I/O distributed along a production line
Water and environmental systems: Remote pump or valve stations
Large industrial equipment: Localized I/O groups connected by serial cable
Material Composition
Enclosure: Industrial-grade thermoplastic module housing
Internal Components: Communication transceiver, processor, status indicators, and printed circuit assembly
Connectors: RS-485 communication port and DL405 backplane connector
Structural Characteristics
Module Format: DL405 rack-installed communication module
Communication Port: RS-485 serial interface
Status Indication: LED or system indicators for operating and fault conditions
Remote Base Support: Interfaces with remote I/O modules installed in compatible DL405 bases
Working Principle
The master remote I/O module communicates with one or more D4-RSDC slave modules over an RS-485 serial link. The slave module maps its remote base I/O data to the master system so that remote input and output devices appear in the central PLC control program.
Installation Requirements
Mounting: Install in a compatible DL405 remote base.
Power Supply: Provide a stable 24 VDC supply within the module’s specified range.
Cabling: Use shielded twisted-pair RS-485 cable.
Termination: Configure network termination and grounding according to the DL405 communication manual.
Addressing: Set the slave address and baud rate to match the master configuration.
Control Cabinet: Install inside a suitable cabinet to maintain the IP20 environment.
Usage Precautions
Termination: Verify termination resistors at both physical ends of the RS-485 network.
Baud Rate Matching: Ensure every node uses the same communication parameters.
Distance Limits: Do not exceed the applicable cable length for the selected baud rate.
Ground Loops: Follow recommended shielding and grounding practices.
Power Quality: Avoid voltage drops or unstable supplies that could reset the remote module.
