Contents

Revision and Copyright Information
Warranty and Assistance
Table of Contents
SDM-SW8A Switch Closure Input Module
- 1. Function
- 2. Specifications
- 3. Power Supply Considerations
- 4. Connections
  - 4.1 Connections to Dataloggers and Other SW8As
  - 4.2 Sensor Connections
- 5. Internal Jumpers
  - 5.1 Address Jumpers
  - 5.2 Measurement Jumpers
- 6. Datalogger Programming
  - 6.1 CRBasic Programming
    - 6.1.1 SDMSW8A Instruction
    - 6.1.2 SDMSpeed Instruction
  - 6.2 Edlog Programming
- 7. Datalogger Program Details
  - 7.1 Datalogger Scan Rate
  - 7.2 First Scan
  - 7.3 Watchdog Reset
- 8. Measurement Applications
  - 8.1 SPDT Switch Closure
  - 8.2 SPST Switch Closure
  - 8.3 DC Voltage Pulse
  - 8.4 Duty Cycle
- 9. Theory of Operation
Appendix A. Edlog Program Example
Campbell Scientific Contact Information

Campbell Scientific SDM-SW8A Instruction Manual

Campbell Scientific SDM-SW8A Peripheral manual cover

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Campbell Scientific SDM-SW8A Peripheral Specification

The Campbell Scientific SDM-SW8A is a sophisticated peripheral device designed to enhance data acquisition systems by facilitating the automated control of up to eight external devices. Engineered for precision and reliability, the SDM-SW8A interfaces seamlessly with Campbell Scientific dataloggers, utilizing the Synchronous Device for Measurement (SDM) protocol to ensure efficient and accurate communication. The device operates as a switch closure output module, capable of controlling devices such as relays, solenoids, and alarms, making it ideal for applications that require precise control over external hardware. Each of the eight switches is independently controlled and can handle up to 30 volts and 2 amps, providing flexibility in managing various power requirements. The SDM-SW8A integrates with the datalogger's sequential control structure, allowing for timed or event-driven operations. With its robust design, the device is housed in a weather-resistant enclosure, ensuring durability and performance in harsh environmental conditions. Power consumption is minimal, reducing the impact on the overall power budget of the data acquisition system. The SDM-SW8A is compatible with a wide range of Campbell Scientific dataloggers and supports easy integration into existing setups. Its versatility and reliability make it an essential component for users who require expanded control capabilities in their data collection and monitoring systems. Overall, the Campbell Scientific SDM-SW8A offers a highly efficient solution for managing multiple external devices, enhancing the functionality and flexibility of environmental monitoring and data acquisition applications.

Campbell Scientific SDM-SW8A Peripheral F.A.Q.

What is the main function of the SDM-SW8A Peripheral?

The SDM-SW8A is used to control up to eight external devices or sensors, allowing them to be switched on or off by a data logger.

How do I connect the SDM-SW8A to a data logger?

Connect the SDM-SW8A to the data logger using the SDM port. Ensure that the wiring is correct as per the user manual, with particular attention to the clock, data, and enable lines.

What should I do if the SDM-SW8A is not responding to commands from the data logger?

First, check all connections between the SDM-SW8A and the data logger. Verify that the power supply is adequate and the correct SDM address is being used. Additionally, check the programming of the data logger to ensure correct configuration.

How can I verify that the SDM-SW8A is functioning correctly?

Perform a simple test by sending known commands from the data logger and observing the output status LEDs on the SDM-SW8A. Each LED should light up when the corresponding channel is activated.

What maintenance is required for the SDM-SW8A?

Regularly inspect the SDM-SW8A for signs of physical damage or corrosion. Ensure that all connections are secure and free from dust and debris. Periodically check firmware updates from Campbell Scientific.

Can the SDM-SW8A be used in extreme environmental conditions?

The SDM-SW8A is designed for use in a wide range of environmental conditions. However, it should be housed in a protective enclosure when used in extreme temperatures or humidity to ensure longevity and reliability.

How do I address multiple SDM-SW8A devices connected to a single data logger?

Each SDM-SW8A must have a unique SDM address. Set the address using the DIP switches on the device, and ensure that each device is correctly programmed in the data logger's configuration.

What troubleshooting steps should I take if the SDM-SW8A channels are not switching as expected?

Verify that the command format sent from the data logger is correct. Check for any potential shorts in the wiring and ensure that the power supply to the SDM-SW8A is stable.

Is it possible to use the SDM-SW8A with non-Campbell Scientific data loggers?

While the SDM-SW8A is optimized for Campbell Scientific data loggers, it can potentially be used with third-party data loggers that support SDM communication protocol, although this is not guaranteed.

What power requirements does the SDM-SW8A have?

The SDM-SW8A requires a 12 V power supply. Ensure that the power supply can provide adequate current for the connected devices.