Compact and flexible components, available at low cost, are in high demand in the plant engineering sector. Thanks to its varied applications, the Gemü 3030 mFlow is a more cost-effective option than some conventional flowmeters.
Magnetic induction as a measurement principle
With this measurement principle, a moving conductor induces a voltage in a magnetic field which is proportional to the speed of the medium. The flowing medium, which must be electrically conductive, (20 μS/cm) is the moving conductor. This makes it possible to measure the flow velocity of liquids precisely. The flow rate is then calculated using the pipe cross section previously entered by the user. Flow velocities of 0,1–10 m/s are measured. Furthermore, the measurement result is largely independent of process pressure, temperature and viscosity.
The flowmeter operates reliably with conducting media in the temperature range of 0 to 135°C with a supply voltage of 24 VDC and an automatic adaptation of the measuring range (0–4 m/s or 0–10 m/s).
The magnetically inductive flowmeter can be used up to a maximum operating pressure of 10 bar and the ambient temperature should not exceed the range 0 to 60°C. Thanks to the low installation depth of the sensor, there is only a negligible loss in pressure.
Simple connection to the plant control system
The system is connected electrically using standard connectors which are fitted to the back of the flowmeter as 5-pin M12 connectors, making it easy to connect without needing to open the housing.
The Gemü 3030 mFlow can be optimally integrated in fully automatic plant control systems using standard signals (analog output 4-20 mA and pulse output 24 VDC) to transmit the flow rate to higher-level plant systems and interfaces such as the RS-232 and Profibus DP.
Status information, error messages and the operating range can be displayed and operated simply and easily thanks to these interfaces. The two visual indicators, integrated in the housing, indicate the status of the Profibus connection. This makes it possible to detect any connection problems in the fieldbus system or faulty data transmission of a device quickly and easily.
Variable application
The accompanying weld-in sleeve enables the meter to be installed in a variety of piping. Nominal sizes from DN 25-300 can be covered with this one device. A bolt hole is simply drilled into the piping so that the weld-in sleeve, the adaptation device for the unit can then be welded in place.
Apart from the weld-in sleeve, in-line housings and wafer-type flanges can be used as fittings. If required, a deadleg-free measurement or a measurement with full flow bore can be achieved. In-line housings by Neumo and Tuchenhagen are suitable for this purpose. These requirements are particularly important in the pharmaceutical and foodstuff industry, but also in the mining industry where pipes without constrictions are advantageous because of abrasion and deposits. The assembly fittings are suitable for all standard process connections and can be combined with one and the same measurement device.
Calibration at the factory ensures the flowmeter is immediately ready for operation once the operating voltage has been connected. However, if required in order to adapt to plant-specific conditions, the magnetically inductive flowmeter can be recalibrated on site, which improves its accuracy at the same time.
Fast and uncomplicated commissioning
In addition to the uncomplicated and fast installation of the Gemü 3030 mFlow, commissioning is simple, with versatile operating facilities, for example using the fascia buttons with illuminated display, PC connection with Internet browser and fieldbus interfaces. No special software is required for browser operation, as this is already integrated in the meter. All that is needed is a standard browser and a current operating system.
Two levels are available for operating the device using the front keyboard. After the supply voltage is switched on, the Gemü 3030 mFlow is at the working level, where the most important system parameters are displayed. It is also possible to adjust the individual display settings. As standard, the current flow rate and the flow velocity are displayed in one metric unit. The user can set and adapt different parameters during operation using the configuration level.
The configuration menu is clearly structured, making the required parameters easy to find, even for new users. A help text, available in different languages, provides additional assistance. This menu can be used to make a number of individual adjustments, e.g. the number of decimal places for the flow rate value and the unit in which the measured value is to be displayed.
Application in many sectors
The Gemü 3030 mFlow is suitable for a wide range of uses in the most varied of industrial sectors. In most cases, this entails the measurement of all types of liquid media.
Thanks to its contactless measurement principle, the flowmeter can also measure media with particles; this means it can be used to measure fruit juices, for example. In addition to the beverage industry, it can also be used in the mining industry, which very often involves work with slurry.
A huge variety of advantages
The unit has extensive diagnostic facilities, enabling errors to be detected and rectified as soon as possible. While conventional sensor and display units only report simple switch signals, the Gemü 3030 mFlow can save all these errors, immediately displaying the current problem using a distinctive error code. The saved error list can then be downloaded to a computer using the implemented RS-232 interface.
Settings can also be made using this connection and are then saved as parameter files, which can, in turn, be loaded onto other devices as required. This enables fast and uncomplicated parameterisation when using more than one device. Furthermore, adjustable relay functions can be used which can report additional information, for example when a flow rate value is exceeded or undershot.
Bi-directional measurement permits installation independent of the flow direction. However, we recommend installation in the flow direction indicated on the devices. Due to the measurement principle, there are no moving parts in the medium.
The Gemü 3030 mFlow contains two totalisers as well. These enable the flow to be determined over a specific time period. Depending on requirements, these totalisers can be reset, enabling hourly, daily, monthly or annual values to be determined. It can also be fitted with a temperature sensor which makes it possible to simultaneously detect the flow rate value and the medium temperature.
The housing is designed to protection class IP65, preventing dust penetration and protecting against water jets, allowing this device to be used in harsh system conditions thanks to its closed housing of high-quality plastic components.
For more information contact Claudio Darpin, Gemü Valves Africa, +27 (0)11 462 7795, [email protected], www.gemu-group.com
© Technews Publishing (Pty) Ltd | All Rights Reserved
printer friendly version