6BAB Thermal Mass Flow Meter Overview
6BAB thermal mass flow meter is an instrument that directly measures gas mass flow based on the thermal diffusion principle. It can output flow values under standard conditions without temperature and pressure compensation, making it suitable for various industrial gas measurement scenarios. This article provides a concise manual to help you quickly understand its principles, parameters, and usage points.
Download 6BAB Chinese Manual.pdf
Working Principle and Core Advantages
Thermal Measurement Principle
The sensor contains two platinum resistance probes, one for heating and one for temperature measurement. When gas flows through, it takes away heat, and the heating power is proportional to the mass flow, thereby directly obtaining the mass flow. This principle is insensitive to changes in gas composition and is suitable for mixed gas measurement.
Main Advantages
- Direct mass flow measurement, no additional temperature and pressure compensation required
- High sensitivity at low flow rates, wide turndown ratio up to 100:1
- Minimal pressure loss, almost no obstruction, good energy-saving effect
- Rugged structure, suitable for harsh industrial environments
Technical Parameters Quick Reference
The table below lists the key performance indicators of the 6BAB thermal mass flow meter for selection and procurement reference.
| Parameter | Typical Value | Remarks |
|---|---|---|
| Measurement Range | 0~120 Nm/s (optional) | Converted according to pipe diameter and gas |
| Accuracy | ±1% FS | Under standard conditions |
| Repeatability | ±0.5% FS | — |
| Operating Temperature | -40~+200°C (probe) | High-temperature version optional |
| Operating Pressure | ≤4.0 MPa | Higher pressure customizable |
| Output Signal | 4-20 mA / RS485 | HART optional |
| Power Supply | 24 VDC | ±10% |
| Protection Rating | IP66/IP67 | — |
Installation and Wiring Steps
Installation Location Selection
Ensure that the upstream and downstream straight pipe sections meet the requirements: upstream ≥10D, downstream ≥5D (D is the pipe diameter). Avoid installing near valves, elbows, or vibration sources to ensure measurement accuracy.
Installation Steps
- Close the pipeline, depressurize, and drain the medium.
- Open a hole in the pipeline and weld the mounting base, ensuring sealing.
- Insert the sensor probe into the pipeline and adjust the depth to the center position.
- Tighten the locking nut, being careful not to overtighten and damage the probe.
- Connect the cable and wire the power and signal lines according to the wiring diagram.
- After power-on, check the zero point and calibrate if necessary.
Wiring Points
- Use shielded cables, with the shield grounded at one end.
- Route power and signal lines separately to avoid interference.
- Confirm the power supply voltage is 24 VDC and the polarity is correct.
Operation and Maintenance Points
Daily Operation
After power-on, the instrument automatically enters measurement mode. Flow, temperature, and other data can be viewed via local buttons or remote communication. If you need to modify the range or output mode, please refer to the complete manual.
Maintenance Recommendations
- Regularly check whether the probe is contaminated and clean it with a soft cloth if necessary.
- Calibrate the zero point and range annually to ensure accuracy.
- Check the aging of seals and replace them in time.
- Avoid live disassembly and assembly in flammable and explosive environments.
Common Questions and Selection Tips
Common Questions
- Low reading: Possibly due to probe contamination or insufficient straight pipe sections.
- No output: Check the power supply and wiring polarity.
- Large fluctuation: Confirm whether the gas flow rate is stable and eliminate vibration interference.
Selection Tips
When selecting, provide the gas type, pipe diameter, flow range, temperature and pressure, and output requirements. For corrosive gases, please choose corrosion-resistant probe materials. 6BAB thermal mass flow meter supports customization to meet different working conditions.