Magnetrol Eclipse 706 GWR - Guided Radar Level Transmitter 706-511A-310 +

7AT-5300-A10-00-035  

The Magnetrol 706 Guided Wave Radar (GWR) transmitter works on the principle of Time Domain Reflectometry (TDR), sending electromagnetic pulses down a probe and measuring the time it takes for a reflected pulse from the liquid surface to return. The time delay is converted into a precise distance, providing an accurate liquid level measurement. The technology is also capable of sensing the interface between two liquids of differing dielectric constants, such as oil and water

Here's a breakdown of the principle:

1. Pulse Transmission: The Model 706 generates a pulse of electromagnetic energy that travels down the GWR probe, which acts as a transmission line.  
2. Reflection: When this pulse reaches the surface of a liquid (or a solid), a portion of the pulse is reflected back up the probe. The amount of reflection depends on the dielectric constant of the material at the surface.
3. Time Measurement: The device's high-speed circuitry precisely measures the time it takes for the pulse to travel from the transmitter to the liquid surface and back.
4. Level Calculation: This measured transit time is then converted into a distance, providing the liquid level reading.
5. Interface Measurement: For applications with two liquids, like oil over water, a portion of the pulse continues past the low-dielectric oil and is reflected again by the higher-dielectric water layer, allowing the transmitter to sense the interface between them.
6. High Sensitivity: The Model 706 incorporates advanced circuitry to reduce noise and enhance signal-to-noise ratio, which improves its ability to detect signals even from very low dielectric media or under turbulent conditions.

Enlarged Coaxial Probe

The Magnetrol 7AT, part of the Eclipse® 700 Series, is a Guided Wave Radar (GWR) level transmitter that operates on the principle of Time Domain Reflectometry (TDR). It sends electromagnetic pulses down a probe or waveguide. When a pulse hits the liquid surface (which has a higher dielectric constant than the vapor), it reflects back to the transmitter. Sophisticated high-speed circuitry measures the time it takes for the pulse to travel and return, and this time is converted into a distance, which is then displayed as the level reading

How it works in detail

1. Pulse Generation: The transmitter generates a short pulse of electromagnetic energy.
2. Probe Propagation: This pulse travels down a metal probe or waveguide.
3. Reflection: When the pulse reaches a liquid surface, a portion of it reflects back to the probe. The strength of this reflection depends on the liquid's dielectric constant.
4. Time Measurement: Ultra-high-speed timing circuitry measures the time it takes for the pulse to travel to the liquid surface and return to the transmitter.
5. Level Calculation: The measured transit time is converted into a distance, which is then displayed as the level of the liquid.

Key Features & Benefits:

• Time Domain Reflectometry (TDR): The core principle of operation.
• Robust Performance: The technology is largely unaffected by changes in media density, turbulence, foaming, boiling, or flashing.
• Interface Measurement: The Eclipse Model 700 can also detect liquid-liquid interfaces by measuring multiple reflections from different dielectric layers.
  Wide Application: The Eclipse transmitter can be used in a diverse range of industrial applications, from light hydrocarbons to water-based media.

 Full Datasheet Devices

Transmitter Feature  

• Manufacturer :  Magnetrol 
• Product No. : 706-511A-310
• Model : Eclipse 706 
• BASIC MODEL NUMBER: 706 -  ECLIPSE 4th Generation Guided Wave Radar (GWR) Level Transmitter
• POWER: 5 - 24 VDC, Two-Wire 
• SIGNAL OUTPUT : 1 -  4–20 mA with HART
• SAFETY OPTIONS: 1 - special certification
• ACCESSORIES/MOUNTING: A -Digital Display and Keypad - Integral
• CLASSIFICATION: 3 - Explosion-proof (FM & CSA CL 1 Div 1, Grps B, C, D)
• HOUSING: 1 - Die-cast Aluminum, Dual-compartment, 45-degree
• CONDUIT CONNECTION:  0  - 1/2" NPT

There are several Model of pressure transmitters, for more details read the PDF below 

Basic Ordering Information Transmitter

Probe Feature  

• Manufacturer :  Magnetrol 
• Product No. : 7AT-5300-A10-00-035
• TECHNOLOGY : 7  - ECLIPSE GWR Probes - Model 706
• MEASUREMENT SYSTEM: A - English
• CONFIGURATION/STYLE (RIGID): T - Enlarged Coaxial, Overfill Standard O-Ring Seal (+200 °C/+400 °F) — Not available with 10th digit N or D
• PROCESS CONNECTION – SIZE/TYPE: 53 - 3" 150# ANSI RF
• CONSTRUCTION CODES: 0 - Industrial
• FLANGE OPTIONS: 0 -  none
• MATERIAL OF CONSTRUCTION - FLANGE/NUT/ROD/INSULATION: A -  316 SS/316L SS (Probe O.D. 45 mm (1.75”))
• SPACER MATERIAL: 1 -  TFE (+200 °C/+400 °F) — Available only with 3rd digit P or T — ε_r ≥ 1.4
• O-RING MATERIALS/SEAL OPTIONS: 0 -  Viton® GFLT — Available only with 3rd digit T
• PROBE SIZE/ELEMENT TYPE/FLUSHING CONNECTION: 0 -  Standard Enlarged Coaxial Probe
• SPECIAL OPTIONS — See datasheet page 94: 0 -  Single Length Probe (Non-Segmented)
• INSERTION LENGTH: 035 - 035" (889mm)

Probe Drawing 

Basic Ordering Information probe