Contents

Revision and Copyright Information
Warranty and Assistance
Table of Contents
MD485 RS-485 Multidrop Interface
- 1. Introduction
- 2. Specifications
- 3. System Components
  - 3.1 MD485 RS-485 Multidrop Interface
    - 3.1.1 Ground Lug
    - 3.1.2 Indicator LEDs
    - 3.1.3 Configuring the MD485
  - 3.2 Power Supplies
  - 3.3 RS-485 Cable
  - 3.4 Serial Cables
- 4. Quick Start
  - Step 1 Set Up Base MD485
  - Step 2 Set Up Remote MD485
  - Step 3 Connect Base MD485 to Remote MD485
  - Step 4 PC400/LoggerNet/PC208W Set-up
  - Step 5 Connect
- 5. System Configuration
  - 5.1 Transparent Communication
  - 5.2 MD9 Emulation
  - 5.3 PakBus Networking
- 6. Combining with Other Devices
- 7. Call-back
- 8. Wiring Specifications
  - 8.1 RS-485 Line Length
  - 8.2 Grounding
  - 8.3 Protection and Isolation
  - 8.4 Termination
  - 8.5 Summary
Appendix A. Phone to MD485 Network
Appendix B. RF401 to MD485 Network
- B.1 Connection using a PS100 with A100
- B.2 Connection using a Null Modem Cable
Appendix C. MD485 to RF401 Network
- C.1 Connection using a PS100 with A100
- C.2 Connection using a Null Modem Cable
Appendix D. Digital Cellular Modem to MD485 Network
- D.1 RavenXT-series, Raven100, and Raven110 Digital Cellular Modems
- D.2 Redwing100 and Redwing105 Digital Cellular Modems
Appendix E. NL100 to MD485 Network
Appendix F. MD485 to CC640 Digital Camera
Appendix G. MD485 to AVW200 Interface
Appendix H. MD485 Port Pin Descriptions
Campbell Scientific Contact Information

Campbell Scientific MD485 RS-485 Instruction Manual

Campbell Scientific MD485 RS-485 Interface manual cover

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Campbell Scientific MD485 RS-485 Interface Specification

The Campbell Scientific MD485 RS-485 Interface is a robust communication device designed to facilitate data transmission between data loggers and peripherals using the RS-485 protocol. This interface is engineered to support multi-drop configurations, enabling the connection of multiple devices over long distances, up to 1200 meters, without significant signal degradation. The MD485 operates across a wide temperature range, from -25°C to 50°C, making it suitable for diverse environmental conditions. It supports both point-to-point and point-to-multipoint communication setups, allowing for versatile deployment in various data acquisition systems.

The device is equipped with an RS-232 port for direct connection to data loggers, computers, or other serial devices, and an RS-485 port for broader network communication. It operates with selectable baud rates ranging from 1200 to 115200 bps, providing flexibility for different data throughput requirements. The MD485 offers half-duplex communication, optimizing it for systems where bi-directional data flow is necessary, yet not simultaneous. It is powered by a DC voltage supply, typically sourced from the data logger or an external power supply, with a low power consumption profile, making it ideal for remote or solar-powered installations.

Housed in a rugged, compact enclosure, the MD485 is designed for easy integration into existing networks, with simple DIP switch settings for configuration. The interface supports protocols such as PakBus, ensuring compatibility with Campbell Scientific's data loggers and software tools. The MD485 enhances the reliability and efficiency of data transmission in complex monitoring systems, making it an essential component for environmental monitoring, industrial automation, and scientific research applications.

Campbell Scientific MD485 RS-485 Interface F.A.Q.

What is the primary function of the Campbell Scientific MD485 RS-485 Interface?

The Campbell Scientific MD485 RS-485 Interface is designed to facilitate communication between dataloggers and other devices over long distances using RS-485 protocol. It enables reliable data transfer in industrial and scientific applications.

How can I connect multiple devices using the MD485?

To connect multiple devices, daisy-chain them using the RS-485 interface. Ensure each device is configured with a unique address and that termination resistors are used at each end of the bus to prevent signal reflections.

What are the troubleshooting steps if there is no communication between devices using the MD485?

First, check all cable connections and ensure they are secure. Verify that all devices are powered on and configured correctly. Inspect for proper termination and ensure that the baud rate and protocol settings match across all devices.

How do I configure the MD485 for use with a CR1000 datalogger?

To configure the MD485 with a CR1000 datalogger, set the baud rate and communication parameters to match those of the datalogger. Use LoggerNet software to establish and test the connection. Consult the user manual for detailed configuration steps.

What maintenance is required for the MD485?

Regularly inspect the MD485 for signs of physical damage or wear. Clean connectors and ensure that the device is free from dust and moisture. Periodically test the communication to ensure optimal performance.

Can the MD485 interface be used in outdoor environments?

The MD485 can be used outdoors, but it should be housed in a protective enclosure to shield it from environmental elements such as rain, dust, and extreme temperatures. Ensure all connections are weatherproofed.

What is the maximum cable length supported by the MD485?

The MD485 supports cable lengths up to 1200 meters (approximately 4000 feet) when using twisted-pair cables, though signal quality should be monitored over long distances to prevent data loss.

How do I update the firmware on the MD485?

To update the firmware, download the latest version from the Campbell Scientific website and use the Device Configuration Utility to upload the firmware to the MD485. Follow the on-screen instructions carefully to complete the update.

What should I do if the MD485 overheats?

If the MD485 overheats, ensure that it is installed in a well-ventilated area and not exposed to direct sunlight. Check for and remove any obstructions to airflow and verify that the device is operating within the specified temperature range.

How can I verify data integrity when using the MD485?

To verify data integrity, use error-checking protocols such as cyclic redundancy check (CRC) and ensure that communication parameters are correctly set. Regularly test data transmission and reception to identify any discrepancies.