The popular loop-powered transmitters we know as guided wave radar (GWR) burst onto the scene in the late 1990s. Here are some insights into this breakthrough technology and the effect it has had on the level measurement world.
In GWR transmitters, the principle of time domain reflectometry (TDR) utilizes pulses of high frequency electromagnetic energy to measure distances. When a pulse reaches a dielectric discontinuity created by the surface of the process medium, the pulse is reflected and modern low power circuitry measures the time of flight.
Magnetrol® experts were among the pioneers in the field of guided wave radar. In 1998, MAGNETROL released the first guided wave radar transmitter, the Eclipse® Model 705. Over the years, the ECLIPSE family has expanded to include a variety of probes for a broad range of applications, an enhanced version of the Model 705, and most recently the high-performance, cutting-edge Model 706 with best-in-class performance.
Initially, the ECLIPSE was not considered to be very revolutionary. Why would a customer use a “RF capacitance-looking device” with a probe? Non-contact devices were also available at that time, and appeared to have clear advantages over a contacting device. With ultrasonic and radar transmitters already carving out their own niche in the marketplace, installing a probe seemed almost archaic.
However, what the process industries have discovered over the past 20 years is that a probe contacting the process medium can be the key to accurate level measurement in those difficult low dielectric, high temperature applications. A probe offers a conductive path into the vessel upon which the extremely low energy signal can travel. This allows the maximum amount of energy to reach the surface, where it is reflected and sent back to the transmitter for interpretation. Liquids with very low dielectrics and specific gravities can be measured accurately. In addition, since the probe is a conductive path that maintains control of the signal, energy is not scattered within the tank where it can encounter objects that can create false targets. In other words, the initial perceived weakness of the product requiring a probe is actually the strength of the entire system.
The ECLIPSE family has also solved many nagging measurement problems over the 20 years of its existence. One major issue often found with radar devices is a relatively low signal-to-noise ratio, or SNR. If there is a noise level interfering with detection of the actual signal, level measurement can be affected. MAGNETROL leads the industry in guided wave radar devices with superior SNR. ECLIPSE devices also feature Overfill Safe Operation, a function that allows the probe to measure true level throughout the tank, with no “dead zones” at the top of the probe.
Difficult process conditions, such as high-temperature, high-pressure, or saturated steam applications, do not affect ECLIPSE devices, which are able to measure accurately even in challenging environments. These are just a few of the ways that MAGNETROL guided wave radar transmitters stand head and shoulders above other radar-based products.
MAGNETROL continues to innovate in the field of guided wave radar, as we have for the past 20 years. To learn more about our transmitters, visit radar.magnetrol.com.