3-Phase Acoustic Separator

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.


Working Pressure 1-10000psi
Temperature 15-150 degrees C
Weight 27 kg
Fluids Reservoir Oil, Gas and Brine
Total volume 390 ml
Maximum change of water volume 200 ml
Maximum change of oil volume 200 ml
Typical volume resolution 0.08 ml
Hysteresis1 0.3 ml
Bandwidth 0.05 Hz
Fittings 1/4 inch AE SpeedBite W
Housing Hastelloy C-276 or Titanium
Transducer Plastics and Epoxy
Bore diameter 25.4 mm
Bore length 384.81 mm
Required Vertical Positioning +/- 2.5 degrees from true vertical

1 Due to fluid surface mechanics, i.e., reversal of the meniscus surface when changing from rising to falling liquid levels or vice versa, a hysteresis effect occurs in the measurements. To minimize this, the user should prepare the inner surfaces of the separator in accordance with section: Cleaning and Preparation.


Sampling frequency Up to 30 Hertz
Warm-up time 30 minutes
“Time of flight” resolution 40 nS
Transducer resonance frequency 1.5 MHz
PC interface EIA RS-232C, ASCII, Quizix PumpWorks compatible, ethernet


Mains supply 100/120, 220/240 AutoSwitching VAC