FAQ

In single-jet water meters the principle of operation is given by the incidence of a single tangential stream of water with a turbine mounted in a radial position within the body of the meter. The rotation of the turbine transmits the motion to the reading mechanism allowing the measurement of the volume of water passing through the meter. The rotation speed of the turbine is proportional to the water flow in inlet and any variation in the relationship between the characteristics of the turbine and the water flow would entail an alteration of the error curve of the meter. In multi-jet water meters the principle of operation is to force the passage of the inlet water flow through a series of ducts open in a capsule called distributor, containing the turbine. The entrance of the water through the ducts generates a series of symmetrical water jets that impact the turbine keeping it in perfect balance.

Metrological checks following the initial verification of heat meters are prescribed by the rules in force in the country where the meters themselves are used. In Italy, for example, the Decree 155 of October 30, 2013 states that the heat meters must be reassessed as follows.

Heat meters with Qp flow up to 3 m³/h
a) with mechanical flow sensor: within 6 years
b) with static flow sensor: within 9 years

Heat meters with Qp flow higher than 3 m³/h
a) with mechanical flow sensor: within 5 years
b) with static flow sensor: within 8 years

The heat cost allocators quantify the amount of energy consumed by a single heating unit through a parameter defined as 'UNIT OF CONSUMPTION ". Such parameter expresses a proportional quantification (dimensionless) of the amount of energy consumed by the heating body on which the allocator is installed. The standard that indicates the requirements for the construction and the algorithm used for the execution of the measurement is the UNI EN 834.

The dry dial water meter has the reading mechanism hermetically separated from the water flow chamber. In this case the transmission to the reading mechanism gears takes place via magnetic coupling between the turbine and the reading mechanism itself. The wet dial water meters has the reading mechanism the reading mechanism completely immersed in the water and the transmission is direct from the turbine to the gears of the mechanism itself. The semi dry dial water meter has the reading mechanism completely immersed in the water but the dial is partially separated from it remaining dry and the rollers are protected in a sealed capsule. The transmission from the turbine to the gears of the reading mechanism is direct.

Heat cost allocators can only be installed on radiators and convectors part of centralized heating systems with both vertical and horizontal distribution. They cannot be installed on fan-coils.

For proper and safe installation and configuration of the B METERS products please refer to the installation and software manuals specific to each product, available in the download area.

As requested by the 2004/22 / EC (MID) Directive and by the norm EN14154, the measuring range of a water meter is determined by the ratio between the value of its permanent flow rate (Q3) and the one of the minimum flow rate (Q1). The meter can measure for short periods, without deteriorating, at the maximum flow rate (Q4).
As an example, if we find reported on the dial of a meter the information Q3 = 2.5 m3 / h R100H, R50V, this means that this meter can be used, when installed horizontally, up to a minimum flow rate of 25l /h while, if installed vertically, up to a minimum flow rate of 50l / h. The overload flow is always 1.25 * Q3, in this case therefore, equal to 3,125m3 / h.

The MPE, positive or negative, on volumes between the transitional flowrate (Q2) (included) and the overload flowrate (Q4) is:
2% with a water temperature ≤ 30 ° C
3% with a water temperature > 30 ° C.
The MPE, positive or negative, on volumes between the minimum flowrate (Q1) and the transitional flowrate (Q2) (excluded) is equal to 5% regardless the water temperature.

For proper and safe installation and configuration of the B METERS products please refer to the installation and software manuals specific to each product, available in the download area.

Metrological checks following the initial verification of water meters are prescribed by the rules in force in the country where the meters themselves are used. In Italy, for example, the Decree 155 of October 30, 2013 states that the meters must be reassessed as follows.

Mechanical water meters: within 10 years
Water meters of static and Venturi type: within 13 years

The MID - Measuring Instruments Directive - (2004/22 / EC) is a European Union directive which aims to harmonize different aspects of the Legal Metrology in all EU member countries. The most important principle established by the Directive is that all measuring instruments, including water and heat meters in possession of an MID certification, can be used in the various EU member countries. The MID Directive was published on April 30, 2004 in the Official Journal of the European Union and has become effective from October 30, 2006. It is currently undergoing a transition period lasting 10 years (expiring in October 2016) that still allows the use of the previous EC Directive approved measuring instruments and implementation of the MID Directive by the individual countries are currently being evaluated .

For proper and safe installation and configuration of the B METERS products please refer to the installation and software manuals specific to each product, available in the download area.