VEGAFLEX 81 Guided Wave Radar Level Transmitter Overview
VEGAFLEX 81 is a guided wave radar level transmitter launched by VEGA, based on the time-domain reflectometry (TDR) principle, suitable for continuous level measurement of liquids and solid bulk materials. The instrument uses a guided rod or guided cable probe, with high measurement accuracy, and is not affected by medium conductivity, temperature, pressure, or vapor.
This Chinese manual is intended to help engineering technicians and procurement personnel quickly understand the installation, wiring, commissioning, and maintenance key points of VEGAFLEX 81.
Main Technical Parameters
| Parameter | Specification |
|---|---|
| Measurement principle | Guided wave radar (TDR) |
| Measuring range | Max. 6 m (guided rod) / 75 m (guided cable) |
| Accuracy | ±2 mm |
| Process temperature | -40 … +200 °C |
| Process pressure | -1 … +40 bar |
| Output signal | 4 … 20 mA / HART, PROFIBUS PA, FOUNDATION Fieldbus |
| Protection rating | IP 66 / IP 67 |
Installation Guide
Installation Location Selection
- Keep away from the feed inlet and agitator to avoid false echoes.
- The guided rod/cable should be perpendicular to the bottom of the vessel, ensuring it is perpendicular to the medium surface.
- Avoid installation in the center of the vessel to prevent multiple reflections.
Installation Steps
- Confirm that the vessel connection size matches the instrument process connection (e.g., G¾, G1½, flange, etc.).
- Slowly insert the guided rod/cable into the vessel, avoiding bending or damage.
- Tighten the process connection to ensure good sealing.
- For the guided cable, use a suitable weight to tension it and keep the cable vertical.
Download VEGAFLEX 81 Chinese manual.pdf
Electrical Connection
Terminal Description
- Supply voltage: two-wire 9 … 32 V DC; four-wire 20 … 253 V AC/DC.
- Output signal: 4 … 20 mA / HART connect to terminals 1(+) and 2(-).
- The shielded wire should be grounded at one end to avoid interference.
Wiring Precautions
- Ensure correct power polarity to prevent damage to the instrument.
- Use shielded cables and keep them away from power cables.
- After wiring, tighten the cable entry to maintain the protection rating.
Commissioning and Operation
Local Display and Buttons
VEGAFLEX 81 can be optionally equipped with a PLICSCOM display module, and menu operations are performed through four buttons. The display content includes level, distance, current value, etc.
Parameter Setting Steps
- Enter the menu and select "Basic Setup".
- Set the medium type (liquid/solid) and dielectric constant range.
- Enter the vessel height and measuring range.
- Perform "false echo suppression" to record false echoes.
- Set the output current corresponding to the level value (0% and 100%).
- Save the parameters and return to the measurement interface.
Troubleshooting and Maintenance
Common Faults and Handling
| Symptom | Possible Cause | Solution |
|---|---|---|
| No current output | Power supply interrupted or reversed polarity | Check power supply and wiring |
| Measured value fluctuating | Guided rod/cable scaling or agitator interference | Clean the probe and re-suppress false echoes |
| Measured value fixed and unchanging | Probe short circuit or electronic module failure | Check probe insulation and replace the electronic module |
Routine Maintenance
- Regularly check whether the guided rod/cable is bent, scaled, or corroded.
- Use a soft cloth and neutral detergent when cleaning to avoid damaging the insulation layer.
- Check whether the terminals are loose every six months.
Summary
VEGAFLEX 81 guided wave radar level transmitter is widely used in chemical, water treatment, food, and other industries due to its high precision and strong adaptability. Correct installation, wiring, and commissioning are key to ensuring long-term stable operation. For the complete Chinese manual, please click the link above to download the PDF file.