tfdz JSN-SR04T / AJ-SR04M Waterproof Ultrasonic Module Instruction Manual

1. Introduction

This manual provides detailed instructions for the installation, operation, and maintenance of the tfdz JSN-SR04T / AJ-SR04M Waterproof Ultrasonic Module. This integrated distance measuring transducer sensor is designed for reliable performance in various environments, including wet and harsh conditions, thanks to its waterproof probe.

The module offers high accuracy, strong anti-jamming capabilities, and low power consumption, making it suitable for a wide range of applications from industrial control to artificial intelligence projects.

2. Product Overview

The JSN-SR04T / AJ-SR04M module consists of a main control board and a waterproof ultrasonic probe connected via a cable. The main board processes the ultrasonic signals, while the probe emits and receives the sound waves for distance measurement.

Figure 2.1: The complete tfdz JSN-SR04T / AJ-SR04M Waterproof Ultrasonic Module, showing the main circuit board connected to the waterproof transducer via a black cable.

Figure 2.2: A close-up view of the main circuit board, displaying various electronic components such as integrated circuits, resistors, capacitors, and the ultrasonic transducer's connection port.

Figure 2.3: The reverse side of the main circuit board, highlighting the JSN-SR04T model designation and the four connection pins labeled +5V, Trig, Echo, and GND, along with their respective functions.

3. Technical Specifications

The following table details the electrical and operational parameters of the JSN-SR04T / AJ-SR04M module:

4. Setup and Wiring

Proper wiring is crucial for the correct operation of the ultrasonic module. Refer to the pinout diagram and the following instructions:

1. +5V: Connect this pin to the positive 5V DC power supply. Ensure a stable power source within the specified voltage range.
2. Trig (RX): This is the control side pin. A short high-level pulse (typically 10µs) on this pin initiates the ultrasonic burst.
3. Echo (TX): This is the receiver pin. It outputs a high-level pulse whose duration is proportional to the time taken for the ultrasonic wave to travel to the object and return.
4. GND: Connect this pin to the ground of your power supply and control circuit.

Important: Always double-check your wiring connections before applying power to prevent damage to the module or connected components. Incorrect polarity or over-voltage can permanently damage the device.

5. Operating Principles

The JSN-SR04T / AJ-SR04M module operates on the principle of ultrasonic ranging. Here's a brief overview of its operation:

1. The module is triggered by a short high-level pulse on the Trig pin.
2. Upon receiving the trigger, the ultrasonic transducer emits 8 cycles of 40kHz ultrasonic sound waves.
3. These sound waves travel through the air, reflect off an object, and return to the transducer.
4. The Echo pin goes high when the sound waves are emitted and stays high until the echo is detected.
5. The duration of the high-level pulse on the Echo pin corresponds to the time taken for the sound to travel to the object and back.

To calculate the distance, use the formula: Distance = (Time of Echo High Pulse * Speed of Sound) / 2. The speed of sound in air is approximately 343 meters per second (or 0.0343 cm/µs) at room temperature. Divide by 2 because the sound travels to the object and then returns.

6. Applications

The versatility and robust design of the JSN-SR04T / AJ-SR04M module make it suitable for numerous applications, including:

• Horizontal Distance Measurement: Accurate measurement of distances in various environments.
• Obstacle Avoidance: Ideal for robotic platforms, autonomous vehicles, and automated systems to detect and avoid obstacles.
• Object Approach Detection: Sensing when an object is within a certain range.
• Traffic Control: Monitoring vehicle presence or distance in traffic management systems.
• Security and Industrial Control: Integration into security systems for presence detection or industrial machinery for position sensing.
• Artificial Intelligence and Research: Prototyping and development in AI and academic research projects requiring distance sensing.

7. Maintenance

The JSN-SR04T / AJ-SR04M module is designed for durability, especially with its waterproof probe. To ensure optimal performance and longevity:

• Keep Clean: Periodically clean the surface of the ultrasonic probe to ensure no dirt, dust, or debris obstructs the sound waves. Use a soft, dry cloth.
• Avoid Physical Damage: Protect the module and its cable from excessive force, sharp objects, or crushing.
• Environmental Conditions: While the probe is waterproof, the main circuit board should be protected from direct exposure to water or extreme humidity unless properly enclosed. Operate within the specified temperature and storage ranges.
• Cable Integrity: Ensure the connecting cable is not kinked, cut, or damaged, as this can affect signal transmission.

8. Troubleshooting

If you encounter issues with your JSN-SR04T / AJ-SR04M module, consider the following troubleshooting steps:

• No Reading or Incorrect Readings:
  • Verify all wiring connections (+5V, Trig, Echo, GND) are secure and correct.
  • Ensure the power supply is stable and within the 5V DC specification.
  • Check that there are no obstructions directly in front of the sensor within the blind zone (25cm).
  • Confirm the object being measured is large enough and positioned to reflect sound waves effectively. Soft, sound-absorbing materials may yield poor results.
• Inconsistent Readings:
  • Check for sources of acoustic noise or other ultrasonic devices in the vicinity that might cause interference.
  • Ensure the module is operating within its specified temperature range. Extreme temperatures can affect sensor performance.
  • Verify the code or control logic for triggering and reading the Echo pulse is correctly implemented.
• Module Not Responding:
  • Confirm power is being supplied to the module.
  • Test the Trig pin with a known high-level pulse to ensure it's receiving the trigger signal.
  • Inspect the module for any visible physical damage.

9. Safety Information

Please observe the following safety guidelines when using the JSN-SR04T / AJ-SR04M module:

• Do not exceed the specified operating voltage of DC 5V. Over-voltage can cause irreversible damage.
• Handle the circuit board with care to avoid electrostatic discharge (ESD) damage.
• Ensure proper insulation and enclosure for the main circuit board, especially in environments where it could come into contact with conductive materials or liquids.
• This product is not intended for life-support systems or applications where its failure could result in injury or death.