Introduction
The Integrated Sensing Systems Inc. (ISS) MassSense® (MS-LFV) is the next step in low flow liquid mass measurement technology by using a patented* microCoriolis™ fluidic sensor utilizing silicon MEMS technology. The traditional components of a steel Coriolis flow meter, are now fabricated using silicon processing technology. The result is a sensor that provides low mass flow measurement in a package smaller than a fingernail. Silicon’s low weight (1/3 that of stainless steel) and very high strength (3x that of stainless steel) makes it a perfect material to construct a low-flow Coriolis mass flowmeter.
Designed for Hazardous Environments
Generally recognized electrical safety requirements were taken into consideration when designing the MS-LFV. It can be installed in almost any pilot plant/lab environment with safety approvals to support the installation. For mounting in exposed locations, the LFV is available with a IP-67 sealed enclosure. A simple low cost installation is possible since the sensor and electronics are packaged in a integrated small enclosure. All electrical connectors are seal protected for reliable long-term operation.
Low Power Operation
The power consumption of the MS-LFV is so low that a solar panel can supply power for remote fluid monitoring applications. For laboratory operation, the power supplied from a computer USB port** is enough to power the unit. For pilot plant or process operation, the unit can be powered using a dedicated DC power supply.
Multivariable Measurement: Temperature, Density and Viscosity
The microCoriolis fluidic sensor at the heart of the MS-LFV is a multivariable sensor. By monitoring the resonant frequency of the silicon microtube, fluid density is available as an option. Embedded in the chip is a platinum RTD temperature sensor. The closely coupled temperature sensor and high thermal conductivity of silicon results in an accurate fluid temperature measurement. A binary fluid concentration can be calculated using measured fluid density and temperature and the embedded polynomial equation available in the MS-LFV. By monitoring the damping effect of the fluid viscosity on tube vibration and careful calibration, fluid viscosity can be measured using the MS-LFV.
Communication Options
Options available to the user for data communication include a case mounted backlit LCD display with push buttons for operation and programming. A USB port is available for connection to a laptop running the included ISS Fluidic Communication Software. This software will graph and store in memory data generated by the MS-LFV. The unit also can be reconfigured with this software. For hazardous area installations, a RS232 serial port is available. Modbus RTU communication protocol is available over the RS232 or optional RS485 serial port. Two current loops (4-20ma) are available for data communication. For long term secure storage, 2 GB of internal flash memory is available as an option.
Performance of microCoriolis Technology
A microCoriolis sensor is the perfect solution for low flow measurement in research, pilot plant and lab applications. Coriolis technology measurement accuracy is not dependent on knowledge of the thermal properties of the fluid. It measures mass flow directly. The small volume, siliconsensing tube, vibrates at high frequency >20kHz, eliminating the effect of external vibration. The mass flow of fluid causes a twist in the vibrating U shaped silicon tube, proportional to the mass flow. The MassSense LFV has a very large dynamic measurement range, from 5 grams/hr to 1000 grams/hr with an accuracy of +/- Z.S. plus +/-0.2% of rate.
MS-LFV Performance Specifications
Liquid Mass Flow Range: 5 to 1000 grams/hr
Zero Stability (Z.S.): +/- 2 grams/hr
Liquid Density Range: 0.6 to 1.3 gram/cc
Density Accuracy: 0.00003 gram/cc
Density Resolution: 0.000001 grams/cc
Operating Temp Range: -20 to 60C
Temperature Accuracy: +/- 0.03C
Max Pressure: 300 psig
Viscosity Range: 0-50 cP
Viscosity Accuracy: 0.2 cP
MS-LFV Additional Capabilities
The MS-LFV has available features that allow for flexibility in installation and operation:
- LCD backlit display with pushbutton programming and operation
- RS232 communication port
- RS485 communication port
- Modbus communication protocol
- Qty (2) 4-20ma outputs, user selectable
- 2 GB of internal flash memory for secure data storage
- External pressure or temperature sensor
- Density and viscosity measurement
- External temperature sensor
MS-LFV Selected Options
Model Code Description MassSense Liquid Flow Meter Code MS-LFV -USB -232 -MOD -VIS -4CF -8CF -LCD -420 -MEM -300PS -ETI -STP -DEN -CON -EXC -IP67 USB data port RS232 data port Modbus communication protocol Viscosity measurement 1/4” Compression fittings 1/8” Compression fittings LCD Display with buttons 4-20ma Outputs 2GB Internal flash memory External pressure sensor, 0-300 psia PT100 Temp input (NA with pressure) PT 100 RTD temperature probe Liquid Density measurement Chemical concentration calculation Hazardous area certificate IP67 Sealed case