Flow Transmitter / Switch OMNI-XF
- Universal flow rate sensor with dynamic diaphragm
- Analog output, two switching outputs
- Clear, easily legible, illuminated LCD display
- Modifiable units in the display
- Designed for industrial use
- Small, compact construction
- Simple installation
Characteristics :
- A thin elastic diaphragm made of stainless steel, which covers the entire flow cross-section, is deflected by the flowing fluid, and thereby pushes against an arched end stop.
- There is a plastic-coated magnet on the diaphragm. When there is a deflection, its magnetic field changes, and this is detected by a sensor outside the area of flow.
- Flexible diaphragm made of stainless steel, with plastic-coated magnet.
- Because the diaphragm only bends, and functions without a bearing, there is almost no frictional effect. The movement therefore occurs practically free of hysteresis, and the test results have very good reproducibility.
- The diaphragm's low bulk results in a short response time. The almost complete covering of the flow cross-section in the neutral position produces very high start-up sensitivity. As soon as the slightest flow exists, the diaphragm is of necessity deflected.
- The evaluation of the entire flow cross-section means that there are no problems when routing pipes. Run-in and run-out sections are not necessary.
- The shaped end stop and the elastic properties of the diaphragm mean that even severe water hammer causes no damage. The low number of medium contact parts guarantees reliable operation and a low tendency to contamination.
- There are flanged connection pieces on the inlet and outlet; these are available in various nominal widths and materials. By removing the four bolts of the flange connection, it is simple to remove the measurement unit for servicing, while the connections remain in the pipework.
- The OMNI transducer located on the sensor has a backlit graphics LCD display which is very easy to read, both in the dark and in bright sunlight. The graphics display allows the presentation of measured values and parameters in a clearly understandable form.
- The measured values are displayed to 4 places, together with their physical unit, which may also be modified by the user. The electronics have an analog output (4..20 mA or 0..10 V) and two switching outputs, which can be used as limit switches for monitoring minimal or maximal, or as two-point controllers. The switching outputs are designed as push-pull drivers, and can therefore be used both as PNP and NPN outputs.
- Exceeding limit values is signalled by a red LED which is visible over a long distance, and by a cleartext in the display. The stainless steel case has a hardened non-scratch mineral glass pane.
- It is operated by a programming ring fitted with a magnet, so there is no need to open the operating controls housing, and its leakproofness is permanently ensured.
- By turning the ring to right or left, it is simple to modify the parameters (e.g. switching point, hysteresis...). To protect from unintended programming, it can be removed, turned through 180 ° and replaced, or completely removed, thus acting as a key.
Option C : Preset Counter with external reset option, complementary switching
outputs and actual value display.
Option C1 : Instantaneous value display with analogue output, pulse-volume
output and totalizer
Options : Through a range of options, the XF system is flexibly adaptable to very varied requirements.
Full metal construction
- The standard version has a plastic body with a pressure resistance of 16 bar. A metalled body (nickelled brass) with a pressure resistance of 100 bar is optionally available. The higher operating pressure requires a combination with metal connection pieces.
- Measurements and switching value settings in the range 1..80 l/min are possible.
High temperature : If the full metal model is fitted with high temperature sensors and a gooseneck, operation at media temperatures up to 150oC is possible.
Note : Operation using the plastic body is also possible at temperatures greater than 70oC. However, it should be noted that this reduces the stability to pressure .
Resistance to backflows :
- With forward flows, the diaphragm pushes against an arched end stop, and is undamaged by flow rates which are significantly higher than the intended metering range, or by water hammer.
- For flows or pressure surges in the reverse direction, in the standard version the diaphragm pushes against a circumferential support ring made of plastic or stainless steel, and almost completely closes the flow cross-section.
- This causes pressure to build up which can damage the diaphragm. In applications where such conditions can arise (e.g. from elastic hoses to the rear of the measuring equipment) the use of the "resistance to backflows" option is recommended.
- Here, the support ring is replaced by another arched end stop made of stainless steel, so that the diaphragm is provided with the same overload and pressure surge resistance in the reverse direction as in the forward direction.
- However, a measurement or setting of switching value in the reverse direction is not possible.