Wolman type water meters can be used for flow rates higher than Qn 15 m3/h. They are thereby distiguished by ensuring especially low head loss, even with high flow rates.
The newly developed measuring insert with a special construction of the turbine where the water flows through, guareantees a high measuring accuracy and long-term stability of the measuring results. Large number rollers on the dry dial counter ensure the readability of the numbers at all times.
Similar to multi-jet meters, Wolman meters measure the velocity of the water flowing through with the help of a turbine. The volume is mechanically calculated through the known volume of the measuring chamber, and indicated with the roller counters in cubic meters, The unique from of the “paddle wheels” enable the Wolman meters to cver a very large measuring range with especially low head loss. Aside-from their construction for high flow rates, they also reliably start measuring with small water quantities.
Active or passive sensors are available for communication with pulse counting modules or automation and control systems. Inductive NAMUR optical and Reed sesnsors can be retrofitted without damaging the calibration seal. Active sensors have a pulse value, depending on the meter size, of either 1 or 10 L/lmp. Reed sensors have a pulse value of 100 L/lmp. Up to 10 m3/lmp depending on the meter size.
The hydrodynamic optimize is reliablity operated already at small flow rates and “upwards” it has enough power reserves to reliably measures flow rate peaks. Especially strong bearings with low friction guarantee a long life of the meter.
Retrofitting with active and passive pulsers is possible at any time without damaging the calibration seal. With the reed sensors, optical and inductive-NAMUR sensors all common sensor variations are posibble and make thr integration in data communication or automation in control system very easy.
Performance Characteristic in Overview
- Removable measuring insert
- Evacuated counter protected from condensation
- Low starting flow and high measuring accuracy
- Integrated filter made of stainless steel
- Hydraulic bearing relieve for long-term measuring stability
- Dry dial counter with large number rollers simplifies the readability
- Retrofittable with active and passive pulsers
- High pressure model PN25/40 upon request
- For cold water to 30°C, with security up to 50°C
- For horizontal installation position
- Optional short installation lengths for DN 80 and DN 100 available
Technical Data :
| Nominal Flow Qn | 15 m3/h |
| Nominal Diameter (DN) | 50 mm |
| Nominal flow secondary meter (Qn) | 2.5 m3/h |
| Overal Length (L) | 270/300 mm |
| Metrological class | B*H |
| Maximum Flow (Short-term)Qmax | 30 m3/h |
| Maximum Flow (Constant) | 20 m3/h |
| Transitional Flow | 1 m3/h |
| Minimum Flow Qmin | 0.15 m3/h |
| Flow rate with 0.1 bar head loss | 20 m3/h |
| Display range | min 0.5 max (9.999.999 m3) |
| Maximum temperature | 30°C |
| Operating pressure, max (PN) | 16 bar |
| Head loss at Qmax | 0.2 bar |
| Flange diameter (D) | 165 mm |
| Height | 228 mm |
| Weight | 14 kg |