With their sensitivity and accuracy, the BONEGA® water-meters contribute to a more equitable clearing of water consumption significantly. They reduce the differences in measurements between the base of a building and the sum of household water-meters. Nowadays, it is one of the most accurate household water-meters worldwide.
After a thoroughly done quality comparison of four best selling dry-running water-meters in the Czech Republic, we have been assessed as the best ones. The tests compared mainly the measurement accuracy, the starting flow-rate, the sanitary requirements etc.
Source: VaK, 2004
According to the measurement accuracy, the water-meter are divided into the A, B and C classes – the A class is the least accurate, the C class the most accurate. In general practice, the water-meters of the “B” class or of the “A” class are installed at the flats almost exclusively. The water-meters of the “C” class are seldom used because of their high price.
All the BONEGA®water-meters are involved into the “B” class, but their parameters come very close to the most accurate “C” class, whereby they surpass a lot of competitors. The metrological stability of the BONEGA water-meters is given mainly by their suitable construction of turbines and both regulating units.
Every manufacturer is obliged to mention the accuracy class on the dial (in the horizontal and vertical position - see the detailed description below).
The proofs on measurement accuracy can be found in the Certificates of Calibration .
The differences between the metrological classes are even multiple (see the Table). In addition, there exist, however, very significant differences between water-meters within the same class.
|Comparison of parameters for the most used flow-rates within the metrological classes A,B,C:|
|Sign||Flow-rate||Class A for DN 15(1/2")||Class B for DN 15(1/2")||Class C for DN 15(1/2")||Class A for DN 20(3/4")||Class B for DN 20(3/4")||Class C for DN 20(3/4")|
|Qmin||Minimum flow-rate (l/h)||60||30||15||100||50||25|
|Qt||Transient flow-rate (l/h)||150||120||22,5||250||200||37,5|
|0,2 Qn||20 % of nominal flow-rate (m3/h)||0,3||0,3||0,3||0,5||0,5||0,5|
|0,3 Qn||30 % of nominal flow-rate (m3/h)||0,45||0,45||0,45||0,75||0,75||0,75|
|0,5 Qn||50 % of nominal flow-rate (m3/h)||0,75||0,75||0,75||1,25||1,25||1,25|
|Qn||nominal flow-rate (m3/h)||1,5||1,5||1,5||2,5||2,5||2,5|
|Qmax||maximum flow-rate (m3/h)||3||3||3||5||5||5|
Chart of the measurement accuracy behavior in individual flow-rates:
Key: Qmin = minimum flow-rate (l/h), Qt = transient flow-rate (l/h), 0,2 Qn = 20 % of nominal flow-rate (m3/h), 0,3 Qn = 30 % of nominal flow-rate (m3/h), 0,5 Qn = 50 % of nominal flow-rate (m3/h), Qn = nominal flow-rate (m3/h), Qmax = maximum flow-rate (m3/h)
The higher is the measurement accuracy, the higher is the probability that
the difference in measured values on the base water-meter and in the sum of
household water-meters will be minimum.
Those proofs can be read in the EHS Certificates, Decision on Approval of the TCM meter and Certificates of Calibration.
BONEGA® water-meters reach the accuracy class “B” in both
installation positions, as ones of the few in Europe. This extraordinary
advantage can be reached through a suitable construction of the bottom (wet)
part of the water-meter.
a very precise seating of the turbine in two bearings (only one is usually used)
the bearings are made of agate
the water-meter includes
not only the upper, but also the bottom regulating board
Is it known that the water-meters seated in the vertical installation position usually show the worse measurement accuracy than in the horizontal position (the turbine bedding has the biggest influence thereon.)
Every manufacturer is obliged to mention the accuracy class on the dial,
separately for the horizontal (“H”) and the vertical (“V”) positions. At the
older water-meters, you can find only one-letter designation (the same class in
both positions) which does not comply with the European requirement more.
The most water-meters available on the market, have usually the B class (H-B) for the “H” position and the worst A class (V-A) for the “V” position. Generally, if a water-meter has a higher accuracy class in the most demanding vertical position, it will be even more accurate in its horizontal position.
a) If B-H A-V is mentioned on a water-meter, it means that the water-meter has the worst A class in its vertical position and the B class in the horizontal position. The most water-meters used in Europe have this design.
b) If only the A letter is mentioned on a water-meter, it means, that the water-meter reaches only the worst A measurement accuracy in both installation positions,
The proofs on very high measurement accuracy of the BONEGA® water-meters can be found for the B class in both installation positions in the measurement results (see Certificates & Declarations) and in the EHS Certificates, Decision on Approval of the TCM meter.
Compare the accuracy of the BONEGA® water-meters with other brands.
Another very important parameter of the water-meter accuracy is at what real minimum flow-rate (not at Qmin specified by the standard) the counter begins to rotate evenly (not by jerks) and thus to register the water flow.
If does not concern the minimum flow-rate Qmin, stated by the standard.
The minimum flow-rate, stated by the standard, for ½” water-meters for the B
class amounts to 30 liters per hour.
The A class permits even up to 60 liters per hour (see measurement accuracy in installation positions)
If 29 liters per hour drop (consciously or unconsciously) by an end user, his
water-meter might not register it at all, even if it is involved within the B
class. Annually, the volume of not-registered water can amount up to 254 040
liters = 254 m3. It corresponds to 516 840 liters for the A class (59 liters per
Unfortunately, some end users misuse this phenomenon consciously whereby unfair differences in clearing among the consumers appear.
An unconscious non-registration of the flow-rate appears at the water-meters of low quality, always in the first stage of water flow or when the water inlet is closed (which happens many times a day) and also if the valves are not tightened (water dropping).
The BONEGA® water-meters show extraordinary values also with the above parameter.
- within the range of 5 – 8 liters, thus even better than required by the
C class (min. 15 l/h).
We thus guarantee better parameters for the response to start (sensitivity), than those specified by the highest class.
The reliability is given especially:
It avoids the water-meter turbine to be blocked by impurities
The blade wheel is bedded on a stainless shaft in an agate bearing
It has a very good influence on the lifetime and the exact measurement behavior within the entire guaranteed period between “re-gaugings”
It is not necessary to use complicated installation tools
TRASCO, spol. s r.o.
1. Máje 1000, Rožnov pod Radhoštěm
phone 571 845 484
mobile 777 141 045, 603 517 342
fax 571 842 284
email [email protected]
The renovations are done obligatory after 4 years on the warm-water
water-meters and after 6 years on the cold-water water-meters. The purpose is
ensuring accuracy and eventual repair.
We provide the renovations:
These renovations are done mainly by our contractual workshop - Brněnské vodárny a kanalizace a.s. Thanks to high quality materials, it is usual enough to clean our water-meters thoroughly and to replace the O-ring. Upon wish, we will provide you with the other contacts to the service workshops in both the Czech and Slovak Republics.
Please see: Confirmation about repairing and calibration from BVK
Recently, we can notice that the repairs (renovations) after 4 or 6 years do not pay off more (as it is in Western Europe). The used water-meters are replaced by the new ones. The household water-meters become“short-time” utility goods.
Within the Czech and Slovak Republics, we are able to ensure both the installations, and the clearings of water consumption or other utilities by means of verified renowned companies.
We provide the completed service, such as:
Within the Czech and Slovak Republics, we offer training for installation and engineering companies.
The usage of quality materials is a warranty for long lifetime. The water-meters are suitable even for multiple renovations.
Within the service, we offer also:
|BONEGA® ND 01A||Water-meter’s nickel-coated brass body for the 1/2" water-meter|
|BONEGA® ND 01B||Water-meter’s nickel-coated brass body for the 3/4" water-meter|
|BONEGA® ND 02||Turbine + magnet + spindle + turbine body|
|BONEGA® ND 03||Main shaft (spindle) made of stainless steel|
|BONEGA® ND 04||Bottom regulating board|
|BONEGA® ND 05||Upper regulating board with ruby bearing|
|BONEGA® ND 06A||Packing "O"- ring underneath the upper regulating board for cold water|
|BONEGA® ND 06B||Packing "O"- ring underneath the upper regulating board for warm water|
|BONEGA® ND 07||Plastic sieve|
|BONEGA® ND 08||Delimitating plastic ring|
|BONEGA® ND 09||Brass securing nut|
|BONEGA® ND 10||"O"-ring for counter tightening|
|BONEGA® ND 11||Separate transparent lid|
|BONEGA® ND 12A||Removable protective plastic lid (blue)|
|BONEGA® ND 12B||Removable protective plastic lid (red)|
|BONEGA® ND 13||Counter device|
|BONEGA® ND 14A||Securing ring (blue)|
|BONEGA® ND 14B||Securing ring (red)|
|BONEGA® ND 15||Seal|
|BONEGA® ND 16||Sealing wire|
1) Nickel-coated brass body
2) Turbine + magnet + spindle + ruby bearing
3) Main shaft (spindle) made of stainless steel
4) Bottom regulating board
5) Upper regulating board with ruby bearing
6) Tightening "O"-ring underneath the upper regulating board
7) Plastic sieve
8) Delimitating plastic ring
9) Brass securing nut
10) "O"-ring for counter tightening
11) Separate transparent lid
12) Removable protective plastic lid
13) Counter device
14) Securing ring
Export Manager: Ing. Michal Hudeček, [email protected]