Contents

Revision and Copyright Information
Warranty
Assistance
Table of Contents
SDM-CD8S 8 Channel Solid State DC Control Module
- 1. Function
- 2. Specifications
- 3. Power Considerations
- 4. Installation
  - 4.1 Wiring
    - 4.1.1 SDM-CD8S Power and Control Connections
    - 4.1.2 Controlled Device Connections
- 5. Address Selection Switch
- 6. Datalogger Instructions
  - 6.1 CRBasic Dataloggers (CR800, CR850, CR1000, CR3000, CR5000, CR9000(X))
  - 6.2 Datalogger Instructions 104 (CR10/10X, CR23X, 21X, CR7) and 29 (older CR7s)
- 7. Theory of Operation
- 8. Program Examples
  - 8.1 Control Temperature and Fans CR1000
  - 8.2 Control Temperature and Fans CR10X
  - 8.3 Control Gas Sampling Based on Time CR1000
    - 8.3.1 Terminology
    - 8.3.2 Data Tables
    - 8.3.3 Initialization Section (between BeginProg and Scan)
  - 8.4 Control Gas Sampling with Timing in Measurement Task CR1000
    - 8.4.1 The Purpose of this Example
    - 8.4.2 Pipeline vs Sequential
    - 8.4.3 TimedControl Instruction
    - TimedControl(Size,Sync_interval, Interval_Units,Default_Value, Index_dest, Source_Array, ClockResetOpt)
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Campbell Scientific SDM-CD8S Instruction Manual

Campbell Scientific SDM-CD8S Module manual cover

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Campbell Scientific SDM-CD8S Module Specification

The Campbell Scientific SDM-CD8S is a versatile and robust control module designed to expand the capabilities of data acquisition systems by providing eight individually controlled digital outputs. This module is primarily used to interface with and control external devices such as relays, solenoids, or other low-power loads. It features high-current sinking outputs that can manage loads up to 30 VDC and 1 A per channel, making it suitable for a range of applications including environmental monitoring and industrial control. The SDM-CD8S operates by communicating with a Campbell Scientific datalogger through the Synchronous Device for Measurement (SDM) protocol, which allows for seamless integration and efficient data handling. This module is capable of being daisy-chained with other SDM devices, facilitating the creation of complex systems without extensive wiring. It supports a user-defined control logic, enabling precise control based on the datalogger's programming. The SDM-CD8S is powered by a 12 VDC external power source, ensuring stable operation even in demanding environments. Its compact and durable design is suitable for field deployment, withstanding harsh conditions while maintaining reliability. This module also includes built-in status LEDs for each channel, providing immediate visual feedback on the output states, which aids in troubleshooting and system checks. Overall, the Campbell Scientific SDM-CD8S offers a reliable solution for expanding digital output capability in data acquisition systems, providing flexibility and control for a wide range of applications.

Campbell Scientific SDM-CD8S Module F.A.Q.

How do I connect the SDM-CD8S Module to a data logger?

To connect the SDM-CD8S Module to a data logger, use the SDM, power, and ground terminals. Ensure that the data logger is properly configured to recognize the SDM address of the module.

What is the maximum number of SDM-CD8S modules that can be connected to a single data logger?

Up to 16 SDM-CD8S modules can be connected to a single data logger, depending on the model and available SDM ports. Check the data logger’s specifications for exact limitations.

How can I troubleshoot communication issues between the SDM-CD8S and the data logger?

Check the wiring connections, verify that the SDM address is correctly set, and ensure that the data logger is correctly programmed. Use a diagnostic program to test communication.

What is the function of the LED indicators on the SDM-CD8S module?

The LED indicators provide visual feedback on the status of each channel. A lit LED indicates that the corresponding channel is active.

How can I reset the SDM-CD8S module to its default settings?

To reset the SDM-CD8S module, cycle the power to the module. Ensure that all connections are secure before restoring power.

What maintenance is required for the SDM-CD8S module?

Regularly inspect the module for signs of physical damage, clean the terminals and connectors to prevent corrosion, and ensure that the module is operating within specified environmental conditions.

Can the SDM-CD8S module drive inductive loads?

Yes, the SDM-CD8S module can drive inductive loads, but it is recommended to use snubber circuits to protect the module from voltage spikes.

How do I configure the SDM address on the SDM-CD8S module?

The SDM address is configured via DIP switches on the module. Refer to the module's manual for specific switch settings corresponding to desired addresses.

What should I do if the SDM-CD8S module outputs are not responding to the data logger commands?

Confirm the wiring connections, check the SDM address settings, ensure that the data logger program is correct, and verify the power supply to the module.

Is it possible to test the SDM-CD8S module outputs without a data logger?

Yes, outputs can be tested manually by applying voltage to the control inputs, ensuring that the module is powered and properly wired.