Model 704 Intermediate Guided Wave Radar Transmitter
The HorizonTM 704 is a loop-powered, 24 VDC liquid level transmitter based upon the revolutionary Guided Wave Radar (GWR) technology. The electronics of the HORIZON 704 is integral mount on the GWR probe and allows local calibration via a 3 pushbutton keypad / LCD screen. HORIZON 704 electronics are compatible with different types of GWR probes each encompassing different application challenges (coaxial or twin rod types).
The transmitter is designed to provide all of the performance advantages of GWR. Available in a nonrotatable, single compartment plastic or aluminium housing, this transmitter offers simple configuration with three push buttons and a 2-line × 8 character liquid crystal display. The Model 704 covers a broad application range by utilising coaxial and twin rod probes.
Operating Principle
HORIZON Guided Wave Radar is based upon Time Domain Reflectometry (TDR). TDR utilises pulses of high frequency electromagnetic energy transmitted down a probe. When a pulse reaches a surface that has a higher dielectric than the vapour space in which it is travelling, the pulse is reflected. High-speed timing circuitry precisely measures the total transit time and provides an accurate measure of the liquid level.
Applications
- Liquids or slurries
- Hydrocarbons to water-based media (dielectric 1.7 – 100)
- Most process or storage vessels
- Bridles and by-pass chambers
- Standard process applications
- Storage and buffer tanks
Features
- Two-wire, 24 VDC loop-powered level transmitter
- Low dielectric measurement capability
- 4.90 m (16 foot) maximum range
- IS (intrinsically safe), XP (explosion proof), and
Non-Sparking approvals
Options
- HART® digital communications
- Display/keypad
- Single compartment cast aluminum or Valox®housing
