Gas Meter

EG25 Nbiot

Why choose it

The EG25 Nbiot meter is a deformable wall volumetric measuring instrument for natural gas, manufactured gas, LPG and technical gases, for industrial use. It is designed and built according to the highest standards, and in compliance with EN1359 and the MID directive.

Measurement precision and accuracy are guaranteed by the production control process and by an automated calibration system, which is used at the internal Metrological Laboratory on 100% of the meters produced.

The quality of the plastic and metal components renders the meters highly sensitive, even with a minimum gas flow, and ensures excellent performance over time.

The accuracy and reliability of the measurement over time is guaranteed by the consolidated mechanical principle of measurement itself, which is performed using a membrane and spool valve system.

EG25 Nbiot is the "electronic" version of Sacofgas’s traditional mechanical meter, which has been integrated with an electronic module having the following characteristics and functions:

LCD display with multi-level menu.
Logging of consumption values.
Remote transmission of the readings (compensated by temperature and pressure).

EG25 Nbiot meter performs the PT type volume conversion at standard reference conditions (basic conditions).

Data protection and the security of programming parameters are ensured by both sealable switches and programmable passwords.

The meters are battery powered.

Normative requirements

ATEX 2014/34/EU Directive
MID 2014/32/EU Directive
Standard EN 1359:1998/A1:2006
OIML R137-1&2:2012
WELMEC 7.2

Characteristics

Power supply: No. 2 size D 3,6 V lithium batteries (estimated battery life > 8 years under standard conditions).
Casing available in galvanized steel sheet painted with polyester paint. Electronic casing in polycarbonate + ABS.
Equipped with mechanical anti-return device.
No. 2 digital outputs (impulsive for correct and programmable binary volume repetition).
High measurement stability.
Low noise and pressure absorption.
Temperature measurement range -25 °C/+55 °C; pressure measurement range 0,8/1,5 bar.
Alphanumeric LCD three lines 16 characters display.
Integrated anti-tampering protection.
6-button keypad for setting basic parameters.
SGERG-88 compressibility formula.
ATEX Zone 1----II 2(1)G Ex ib [Ex ia Ga] T3 IIB T3 Gb -25 ≤ T amb ≤ 70 °C.
Membrane in synthetic material.
The meter with galvanized steel sheet casing guarantees excellent corrosion protection and is resistant to high temperatures "T" according to EN1359:1998/A1:2006 standard (at 100 mbar).
Device according to UNI TS 11291-3 and UNI TS 11291-5D.
Cert. B n° I-2142-MI002-TG052 Rev. 0 MID - 26.10.2023.

Data Communication

Nbiot communication (narrow band)
DLMS data communication protocols.
Local communication via ZVEI infrared optical port according to EN 62056-21.

Functionality

The pressure difference between the inlet and outlet of the meter results in the cyclic filling and emptying of the measuring chambers through the alternating movement of the deformable membranes.

The motion is converted into electrical pulse signals via the kinematic measuring system, consisting of spool valves with a connecting crank-rod coupling, and an electronic transduction module, the motion is converted into impulsive electrical signals transmitted to the metrology board.

The transduction module has a temperature sensor for volume correction and is equipped with an effective fraud detection system.

A pressure sensor is also installed on the metal body to compensate the measured volumes.

The measured volume is converted using an algorithm that requires the following variables:

The volume of gas acquired by the transduction module.
Temperature: measured by an integrated sensor.
Gas pressure: measured by an integrated digital transducer.

The device calculates the gas compressibility ratio using standard methods or a constant value, and then provides the value of the converted volume (in standard m³).

Technical features EG25 Nbiot

Operating temperature	-25 °C / + 55 °C
Storage temperature	-25 °C / + 70 °C
Basic conditions temperature	15 °C
Accuracy class	1,5
Degree of protection	IP66
Mechanical Class	M2
Electromagnetic environment	E1
Standard connection (According to ISO 228-1)	2 ½"
Cyclic volume	10 dm³
Class	G 25
Max working pressure	500 mbar
Min flow rate (m³/h)	0,25
Max flow rate (m³/h)	40
Inter-axes distance	335 mm
Dimensions (mm)	A 335 B 422,5 C 142,6 E 184,2 F 472,8

Features and specifications approximate and subject to change.