Thermistor type: VF series
This flowmeter is a kind of vortex shedding flowmeter, which makes use of the regular and periodic characteristics of Karman vortex street. A thermistor sensor picks up changes in flow velocity that come with vortex shedding in the manner - changes in thermistor temperature — changes in resistance value — a train of pulses proportional to the flow velocity.
In the gas purge type, changes in fluid velocity that come with vortex shedding are replaced by changes in fluid velocity of a purge gas (clean gas) introduced from an external source. Thanks to this arrangement, the thermistor sensor constantly remain in contact with clean, room temperature purge gas, permitting precise flow measurement of gases containing dust and mist, high or low temperature gases, or others previously thought difficult to be measured.
Specification
| Type | VF series | |||
| Standard | Gas purge | Insertion | ||
Nominal size |
Wafer type (fixed sensor) |
20 to 150mm | 50 to 150mm | - |
| Flange type (replaceable) |
200 to 500mm | 50 to 150mm | - | |
| Acceptable pipeline diameter |
- | - | 200 to 2000mm (mounts on a 100mm flange) |
|
| Flow range |
Gas (0.2MPa air) |
3 to 19000m3/h | 21 to 19000m3/h | 239 to 339000m3/h |
| Operating temp. range | - 30 to 130°C (in SUS304) |
- 30 to 130°C (for ambient) Max. 350°C (for high temp.) Min. -196°C (for low temp.) |
- 30 to 130°C | |
| Max. operating pressure | 5MPa, but 1.89 for 400mm and bigger (Depends on process connection rating) |
0.971MPa | 3.04MPa | |
| Accuracy | ± 1% of RD | ± 1% of RD | ± 2% of FS | |
| Converter | Display | No display or analog instantaneous flow rate indication (with pointer) | ||
| Output | Pulse | |||
| Power source | 32VDC | |||
| Configuration | Non-explosionproof or explosionproof |
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Applicable Fluid:
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