Contents

Revision and copyright information
Table of contents
1. Introduction
2. Precautions
3. Initial inspection
4. QuickStart
5. Overview
6. Specifications
- 6.1 Integrated temperature sensor
7. Installation
- 7.1 Wiring
- 7.2 Programming
  - 7.2.1 SDI-12 programming
  - 7.2.2 RS-232 programming
  - 7.2.3 RS-485 programming
- 7.3 Beam angle
- 7.4 Mounting height
  - 7.4.1 Reference point
- 7.5 Mounting
8. Operation
- 8.1 Quality numbers
- 8.2 Temperature compensation
- 8.3 SDI-12 measurements
- 8.4 Measuring multiple SDI-12 sensors
9. Maintenance and troubleshooting
- 9.1 Disassembly/assembly procedures
- 9.2 Data interpretation
- 9.3 Data filtering
Appendix A. Importing Short Cut code into CRBasic Editor
Appendix B. Jumper settings
Appendix C. RS-232 and RS-485 operation
- C.1 RS-232 wiring
- C.2 RS-485 operation
- C.3 RS-485 wiring for direct data logger connection
- C.4 RS-485 wiring using an MD485
- C.5 RS-232 and RS-485 settings
  - C.5.1 Baud rate setting
  - C.5.2 Address
  - C.5.3 Operational mode setting
    - C.5.3.1 Measure in poll mode
    - C.5.3.2 Auto measure auto output mode
    - C.5.3.3 Auto measure polled output mode
  - C.5.4 Distance to target or depth
  - C.5.5 Distance to ground
  - C.5.6 Measurement interval units
  - C.5.7 Measurement interval value
  - C.5.8 Quality output
  - C.5.9 Diagnostics output
- C.6 Serial commands
- C.7 RS-232/RS-485 data output format
Appendix D. SR50AH heater operation
- D.1 Heater specifications
  - D.1.1 Heating cable requirements
- D.2 Heater maintenance
Appendix E. SDI-12 sensor support
- E.1 SDI-12 command basics
  - E.1.1 Acknowledge active command (a!)
  - E.1.2 Send identification command (al!)
  - E.1.3 Start verification command (aV!)
  - E.1.4 Address query command (?!)
  - E.1.5 Change address command (aAb!)
  - E.1.6 Start measurement commands (aM!)
  - E.1.7 Start concurrent measurement commands (aC!)
  - E.1.8 Start measurement commands with cyclic redundancy check (aMC! and aCC!)
  - E.1.9 Stopping a measurement command
  - E.1.10 Send data command (aD0! aD9!)
  - E.1.11 Continuous measurement command (aR0! aR9!)
  - E.1.12 Extended commands
- E.2 SDI-12 transparent mode
  - E.2.1 Changing an SDI-12 address
- E.3 References
Limited warranty
Assistance
Safety
Campbell Scientific Regional Offices

Campbell Scientific SR50A Product Manual

Campbell Scientific SR50A Sensor manual cover

Pages 66

Year 0

Language(s)

of 66

Campbell Scientific SR50A Sensor Specification

The Campbell Scientific SR50A Sensor is an advanced ultrasonic distance sensor designed for precise and reliable measurements of snow depth and other distance-related applications. It operates on the principle of ultrasonic echo ranging, emitting a sound pulse towards the target surface and measuring the time it takes for the echo to return. This sensor is capable of delivering accurate measurements in a variety of environmental conditions, including extreme cold and high humidity, making it ideal for meteorological, hydrological, and environmental research applications.

The SR50A features a robust construction with a high-strength aluminum body and a weather-resistant design, ensuring durability and long-term performance in harsh outdoor environments. It operates over a temperature range of -45 to +50 degrees Celsius, allowing for deployment in diverse climatic conditions. The sensor has a measurement range from 0.5 to 10 meters with a resolution of 0.25 millimeters, providing high precision in distance assessments.

For ease of integration, the SR50A supports multiple communication protocols, including SDI-12, RS-232, and RS-485, facilitating compatibility with a wide range of data loggers and systems. The sensor's power consumption is low, requiring only 0.6 watts during measurement, which is advantageous for remote or solar-powered installations. Additionally, the SR50A incorporates a unique temperature compensation algorithm to correct for variations in speed of sound due to ambient temperature changes, enhancing the accuracy of its readings.

Overall, the Campbell Scientific SR50A Sensor is a reliable and versatile tool for measuring distances in challenging environmental settings, offering high precision, robust construction, and flexible integration options.

Campbell Scientific SR50A Sensor F.A.Q.

What is the proper way to install the SR50A Sensor for optimal performance?

The SR50A Sensor should be mounted securely at a height above the surface that is within its measurement range. Ensure it is positioned perpendicular to the surface for accurate readings and away from obstructions that could affect the ultrasonic signal.

How can I troubleshoot if my SR50A Sensor is not producing any readings?

First, check the power supply and ensure the sensor is receiving the correct voltage. Verify all wiring connections are secure. Use a diagnostic tool or software to check if the sensor is responding and if any error codes are present.

What maintenance procedures should be regularly performed on the SR50A Sensor?

Regularly clean the sensor's transducer with a soft cloth to remove dust and debris. Inspect wiring for any signs of wear or damage, and check mounting hardware to ensure it remains secure.

How do I calibrate the SR50A Sensor to ensure accurate measurements?

The SR50A is factory-calibrated and typically does not require regular calibration. However, you can perform field checks by comparing readings with a known reference. If discrepancies are found, consult the manual for calibration procedures.

What should I do if the SR50A Sensor's readings are inconsistent?

Check for any environmental factors such as wind or temperature variations that could affect readings. Ensure the sensor is free of obstructions and that the surface being measured is stable and uniform.

Can the SR50A Sensor be used in extreme weather conditions?

Yes, the SR50A Sensor is designed to withstand harsh weather conditions, but it is recommended to check the sensor's specifications regarding temperature and humidity limits to ensure optimal performance.

What are the common error codes on the SR50A Sensor and their meanings?

Common error codes include 'E01' for low signal strength and 'E02' for signal obstruction. Refer to the sensor's manual for a detailed list of error codes and troubleshooting steps.

How can I integrate the SR50A Sensor with a data logger?

The SR50A can be connected to a data logger via its RS-232 or SDI-12 interface. Ensure you configure the data logger to recognize the SR50A's output format and set appropriate parameters for data collection.

What steps should be taken if the SR50A Sensor is damaged?

Inspect the sensor for visible damage. If repairable, follow the manufacturer's repair instructions or contact support. For irreparable damage, replacement may be necessary. Ensure to diagnose the cause to prevent future occurrences.

How do I update the firmware on the SR50A Sensor?

To update the firmware, connect the SR50A Sensor to a computer using the appropriate interface cable. Use the manufacturer's software to download and install the latest firmware version. Follow the on-screen instructions to complete the update.