SG25

Static measuring principle

The measurement is performed in static mode (without moving mechanical parts) and is expressed in m3 at base conditions (standard m3) on the meter display.

The default base conditions are:

• Tb=15°C
• Pb=1013,25mBar

The technology is based on a MEMS sensor that measures the temperature differential between two detection points and is proportional to the gas flow through them.

Additional sensors allow the measurement of the temperature and pressure of the gas inside the meter.

The internal fluid dynamics are designed to allow high immunity to any contaminants present in the gas.

The system maintains measurement accuracy even in the presence of variations in gas composition within groups H and L, as defined by the EN437 standard; The measurement of some characteristics of these gases makes it possible to compensate for the effects due to the change in density.

The measurement principle also makes it possible to identify the presence of air inside the meter; This allows air to be used for its calibration and to generate an alarm if the phenomenon occurs after installation.

The meters can work with biogas mixtures and with a maximum H2 percentage of 20%.

Hardware

• System with two processors, one for measurement and a second for communication
• Battery powered; There are two replaceable batteries, one for measurement and one for communication
• Devices for detecting any unauthorized access
• Alphanumeric display and icons for the presentation of metrological and additional data
• 6-button front keypad for menu navigation
• Digital outputs for pulse repetition of measured volume

Connectivity

The meters are equipped with an NBIoT modem for remote data communication and for updating the application software.

• DLMS communication protocol compliant with UNI/TS 11291-13 
• Local interface via optical port compliant with EN 62056-21 and DLMS UNI/TS 11291-13 protocol.
• Internal antenna with provision for remote antenna connection.
• Field replaceable microSIM accessible from the battery compartment without removal of metrological seals.

Data management

• Totalization Base Volumes and Volumes measured under error condition
• Management of 3 tariffs and consumption based on weekdays, holidays and daylight saving time.
• Management of hourly and daily consumption
• Alarm log management
• Event Log Management
• Error Log Management
• Message management for user

Approvals

The SD10/16/25 meters have been verified and approved according to the following directives:

• MID Directive 2014/32/EU, EN17526 standard
• ATEX Directive 2014/34/EU, EN60079-0; EN60079-11 standards
• RED Directive 2014/53/EU