Manufacturer: Vindum Engineering
Model Number: NERAS3000
The NERAS-3000 measures the level of two fluids and a gas in a gravity-based 3-phase high-pressure separator. It provides output signals (serial, ethernet) proportional to either absolute level or relative to a user-selectable set-point.
NERAS-3000 measurements are carried out under the control of one or more embedded computers in the electronics console. The acquisition process starts when the control system initiates an ultrasonic pulse transmitted from the transducer. The ultrasonic energy is transmitted into the fluid in the vessel. This energy wave first encounters the reference target that is placed a known distance away from the transducer face. Some of the transmitted energy is then reflected back to the ultrasonic transducer. This reflection from the target is received by an ultrasonic amplifier and routed to the data acquisition subsystem and stored in memory.
However, most of the ultrasonic energy passes by the reference target and continues past. When a fluid interface is reached, again some of the energy is reflected back toward the ultrasonic transducer. This reflected signal is also acquired and saved to be processed.
The embedded computer processes this information, automatically matching the acquired waveforms with a stored reference waveform. From this match an accurate and stable “pick time” can be calculated.
The system automatically calibrates out any pressure and temperature effects on the fluid by using the information from the reference target waveform. The speed of the heavy fluid is then calculated. Next the arrival of the fluid interface is processed, and along with the stored vessel geometry information, the fluid volumes can be calculated. This information is then displayed on the video output, and is made available to the digital serial link, if present.
This entire process is automatic and does not require any user intervention or threshold adjustments. In addition, the raw waveforms and a plot of the match quality is displayed on the video output. This makes the NERAS-3000 one of the easiest and most reliable ultrasonic level measuring systems available.