Radar level sensors are utilized in the continuous level measurement of conductive or non-conductive liquids, pulps, and slurries. The sensors have two primary technologies: Non-Contact and Guided Wave. Both radar sensing technologies operate on the well-known time domain reflectometry (TDR) principle. Radar technology is unaffected by the properties of the media and the space above it. Measurement is also unaffected by the change in the physical properties of the materials, such as temperature or pressure.
Types of Radar Sensors:
Non-Contact Radar Sensors
Non-contact radar sensors send microwaves signals through the air. As soon as the impulse reaches the surface of the media, it reflects back to the electronic module. Level distance is directly proportional to the flight time of the impulse and the reflected signal is dependent on the dielectric constant of the media.
Non-Contact Radar Benefits
- The non-contact design eliminates the requirement of material compatibility between the liquid and the sensor since it's a through the air sensing technology.
- The non-contact design also ensures no issues with viscous medias coating contact-based sensors.
- Non-contact level sensors do not require the routine cleaning that contact-based sensors require.
- Non-contact level sensors are smaller by design, reducing shipping cost and transit time compared to large probes on guided wave radar sensors.
- Non-contact level sensors' small design reduces installation time, and the amount of personnel needed to install.
- Minimal upper and lower dead bands compared to guided wave radar sensors.
- Bluetooth connectivity is available for simple tank configuration and measurement viewing.
Non-Contact Radar Features
- Non-contact
- 2" NPT mounting
- PVDF housing
- Intrinsically-Safe
- UL/c-UL
- ATEX
- IECEx
- 50’ (15m) sensing range
- 0.2” (5mm) accuracy
- Modbus
- 4-20mA
- Bluetooth®
- IP 67
- 15' or 30' TPE Jacketed Cable
- 1 ¼”-12 For Bracket Mounting
- Full vacuum to 43 PSI (3 bar)
- -40° to 176° F (80° C)
Guided Wave Radar Sensors
Guided wave radar sensors send microwaves along a probe or cable. When the impulse reaches the surface of the media, it also reflects back to the electronic module. In guided wave radar, level distance is directly proportional to the flight time of the impulse and the reflected signal is dependent on the dielectric constant of the media.
Guided Wave Radar Benefits
- Works in lower dielectric liquids, 1.4 versus two on non-contact radar sensor.
- Higher temperature and pressure rating than non-contact radar sensor.
- More extensive sensing range, 80' (24m) versus 50' (15m) on non-contact radar sensor.
- Built-in display for local measurement viewing and configuration.
Guided Wave Radar Features
- Multiple mountings
- 316 Stainless Steel Probes and Cables
- 80’ (24m) sensing range
- 0.2” (5mm) accuracy
- 4-20mA
- Local display
- IP 67
- ½” NPT Conduit Connection
- Full vacuum to 580 PSI (40 bar)
- -22° F (-30° C) to 194° F (90° C)