QDW90A Pressure Transmitter Instruction Manual

1. Product Overview

The QDW90A Pressure Transmitter is a high-accuracy pressure sensor designed for a wide range of industrial applications. Constructed from 304 stainless steel and featuring IP65 protection, it offers reliable performance in various working conditions. This device is certified with CE, FCC, and RoHS standards.

2. Key Features

• High Accuracy: Available with 0.2% FS standard accuracy, and 0.1% FS for higher precision requirements.
• Robust Construction: Made from 304 stainless steel, ensuring durability and resistance to corrosion.
• Environmental Protection: IP65 rated, providing protection against dust and water jets.
• Wide Temperature Range: Features a wider temperature compensation range of -10°C to 70°C, suitable for outdoor use and ensuring accuracy in varying ambient temperatures.
• Low Temperature Drift: Advanced motherboard design minimizes temperature drift for stable and consistent performance.
• Strong Electromagnetic Compatibility (EMC): Upgraded circuit board design enhances reliability in electromagnetically noisy environments.
• High Sensitivity & Fast Response: Ensures precise and quick operation for pressure control applications.
• Pulse Damping: Reduces cavitation and protects the sensor diaphragm from peak pressure impacts.

Image: High accuracy (0.2% FS) and reliable guarantee from German imported components.

Image: IP65 protection and 304 Stainless Steel material for durability.

Image: Wider temperature compensation range (-10°C to 70°C) for outdoor suitability.

Image: Low temperature drift for stable and reliable measurements.

Image: Circuit board upgrade for stronger electromagnetic compatibility (EMC).

Image: High sensitivity and fast response for precise pressure control.

Image: Pulse damping mechanism to protect the sensor from pressure spikes.

3. Setup and Installation

3.1 Selecting the Right Transmitter

To ensure optimal performance, select the appropriate pressure transmitter based on your specific application requirements. Consider the following parameters:

1. Measuring Range: Determined by the measuring medium (e.g., negative pressure, air tightness test, constant pressure water supply, hydraulic pressure, large range).
2. Connection Thread: Common options include M20*1.5 (default), M14*1.5, G1/4, G1/2. Customization may be available.
3. Output Signal: Available options are 4-20mA, 0-10V, 0-5V, and RS485.

Image: Guide for selecting the correct pressure transmitter parameters.

3.2 Physical Installation

The QDW90A Pressure Transmitter features a standard M20*1.5 thread for connection. Ensure the thread size matches your system's requirements. Tighten securely to prevent leaks, but do not overtighten.

Image: Dimensional drawing of the QDW90A Pressure Transmitter.

3.3 Electrical Wiring

The default power supply for the QDW90A is 12-30VDC. Ensure correct polarity and voltage to avoid damage. The transmitter comes with a cable for connection. Refer to the specific wiring diagram for your chosen output signal type:

Image: Wiring diagrams for various output signals (2-wire, 3-wire, RS485).

• 2-Wire System: Connect Power+ (Red wire) and Signal (Yellow/Green wire) to your system. Power- (Black wire) is typically connected to the common ground.
• 3-Wire System: Connect Power+ (Red wire), Signal (Yellow/Green wire), and Power- (Black wire) as indicated in the diagram.
• RS485 Output: Connect A (Yellow wire), B (Green wire), Power+ (Red wire), and Power- (Black wire) according to the RS485 standard.

4. Operating Instructions

Once installed and wired correctly, the QDW90A Pressure Transmitter will continuously measure pressure and provide the selected output signal. It is suitable for measuring pressure in water, liquid, oil, and gas media.

4.1 Typical Applications

• Constant pressure water supply systems
• Hydraulic systems
• Vacuum negative pressure monitoring
• Air pressure testing
• General process control and laboratory equipment

Image: Versatile applications for water, liquid, oil, and gas.

5. Maintenance

The QDW90A Pressure Transmitter is designed for low maintenance due to its robust construction and advanced features.

• Cleaning: Periodically clean the exterior of the transmitter with a soft, damp cloth. Avoid using harsh chemicals or abrasive materials.
• Inspection: Regularly inspect the wiring and connections for any signs of wear, corrosion, or damage. Ensure all connections remain secure.
• Environmental Considerations: The IP65 rating provides good protection, but avoid prolonged submersion or exposure to extremely harsh conditions beyond the specified operating temperature range.

6. Troubleshooting

If you encounter issues with your QDW90A Pressure Transmitter, consider the following basic checks:

• No Output/Incorrect Reading:
  • Verify the power supply voltage is within the specified 12-30VDC range and polarity is correct.
  • Check all wiring connections for looseness or damage.
  • Ensure the measuring range of the transmitter is appropriate for the applied pressure.
  • Confirm the output signal type (4-20mA, 0-10V, 0-5V, RS485) matches your receiving equipment.
• Unstable Readings:
  • Check for excessive vibration in the installation environment.
  • Ensure the medium is stable and free from sudden pressure fluctuations. The pulse damping feature helps, but extreme conditions can still affect stability.
  • Verify ambient temperature is within the compensated range (-10°C to 70°C).

For persistent issues or complex problems, please contact customer support for assistance.

7. Specifications

8. User Tips

• The transducer offers a fast response time, making it suitable for dynamic pressure monitoring.
• The product typically comes with a cable for convenient installation.
• For outdoor installations, the wider temperature compensation range (-10°C to 70°C) helps maintain accuracy.
• If you require higher precision, consider models with 0.1% FS accuracy.

9. Warranty and Support

9.1 After-Sales Service Policy

• We provide technical services and professional technicians to assist with product usage.
• During the 2-year warranty period, if the product has quality problems, you can enjoy free maintenance services. If it cannot be repaired, it will be replaced with a new one free of charge.
• If the quality problem is due to the customer's use, free maintenance is still provided, but the customer needs to bear the round-trip shipping costs.

9.2 Contact Support

For any questions, technical assistance, or warranty claims, please contact our customer support team. Provide your product model (QDW90A) and a detailed description of the issue for efficient service.