English
ItalianoIMP-8FC + ALIMP-8
IMP-8FC is a type 1 electronic gas volume conversion device, a data logger and a communicator. It is in compliance with the Italian regulation UNI/TS 11629:2016 “Sistemi di misurazione del gas - Sistemi di misurazione del gas su base oraria direttamente allacciati alla rete di trasporto”, class 1 or class 2.
The IMP 8FC uses the energy produced by the ALIMP 8 device as primary power supply source.
The ALIMP 8 can be powered by 230Vac mains electricity or by 12Vdc or by 24Vdc.
ALIMP 8 is installable in safe zone. A GPRS/GSM/SMS 3G modem is installed on ALIMP 8.
A backup battery integrated in the IMP-8FC device ensures full functionality in case of lack of primary power supply.
IMP 8FC complies with the standard UNI EN12405 1:2010 and meets the MID requirements according to the annex MI 002 (gas volume electronic conversion device) according to the Welmec 7.2 Issue 5 guide.
The gas compressibility computation is carried out according to the follow norms:
- ISO 12213-2 (AGA8-92DC) (Only Class 2 device)
- ISO 12213-3 (SGERG-88)
Measured volumes are converted into standard or base volumes, at reference values of 0°C or 15°C and 1,01325 bar, according to the EN12405 1:2010 regulation. These values are programmable by user.
Physical parameters necessary to implement the gas compressibility law and the conversion factor are::
GAS TEMPERATURE (T)
Measured by a temperature probe connected to the module
GAS PRESSURE (P)
Measured by a pressure transducer connected to the module
GAS VOLUME (Vm)
Measured by the gas meter pulse emitter (HF or BF).
The scale factor of the acquired pulses, both BF and HF, is programmable.
In case of HF input, the volumes can be corrected by a programmable table of 10 values.
PARAMETERS TO DEFINE THE CHEMICAL/PHYSICAL CHARACTERISTICS OF MEASURED GAS
Values can be programmed either locally or remotely, using the communication protocol, or they can be received from a gas chromatograph or gas quality analyzer connected to the dedicated serial port.
This device elaborates the measured volume (Vm) and transforms it into base volume (Vb) using parameters acquired on the field (P and T) and the whole of the gas parameters to compute Zb/Z as described above.
where:
Vm = Volume at measurement conditions (in case of HF is the corrected volume)
Vb = Volume converted at base conditions
T = Gas temperature at measurement conditions
Tb = Absolute temperature at base conditions
P = Absolute pressure of the gas at measurement conditions
Pb = Absolute pressure of the gas at base conditions
Z = Gas compressibility factor at measurement conditions
Zb = Gas compressibility factor at base conditions
C = Conversion factor
All parameters relevant to metrological purposes are protected with seals according to EN12405-1:2018
Temperature (T)
PT1000
Pressure (P)
Endress Hauser pressure transducer
Volume (Vm)
Low frequency input (max 3Hz)
High frequency input (max 10KHz) (Only Class 2 device)
Received pulses are multiplied by the pulse weight
QUALITY ANALYZER OF GAS OR GAS CHROMATOGRAPH
Gas parameters can be modified, without generating a MID event, if a gas quality analyzer is connected. In this case the presence of the quality analyzer must be enabled in conformity to the programmed calculation formula AGA-8 or sGERG-88 or GERG-2008 or AGA-NX19 mod.
PARAMETERS DISPLAY AND PROGRAMMING
Parameters are displayed on the IMP-FC backlit graphic display. Metrological data is composed of the following:
Volumes at measurement conditions (Vm)
Corrected volumes (Vc)
Converted volumes (Vb)
Energy (E)
Conversion factor (C)
Compressibility factor (Z)
Pressure at measurement conditions (P)
Temperature at measurement conditions (T)
All gas chemical/physical characterization parameters (gas parameters)
STORAGE
Acquired and computed parameters are stored in a temporal recording section. Among others are stored the following:
- monthly traces for 12 months
- daily traces for 12 months
- 15 minutes traces for 31 days
Communication functions as stated in the Italian UNI CIG norm or ModBus RTU protocol through ALIMP 8 device
TECHNICAL SPECIFICATIONS
| Dimensions | 190 x 130 x 100 mm |
|---|---|
| Weight | 1500g |
| Ambient temperature | -30°C ÷ +65°C |
| Gas temperature | -20°C ÷ +60°C |
| Protection level | IP65 |
| Power supply |
From ALIMP8-FC Internal battery pack Li Ion 3,6Vdc (only Class 1 device) Battery life > 5 years for MID section (only Class 1 device) |
| Pressure sensors |
Connected with shielded cable and MID seal applied in factory Measurement range: 0,8÷2,5 bar absolute 0,8÷6 bar absolute 2÷6 bar absolute 2÷10 bar absolute 5÷20 bar absolute 8÷40 bar absolute 10÷80 bar absolute |
| Temperature probe | Pt1000 4 cables class A, connected with shielded cable and MID seal applied in factory. Ø 6mm |
| Digital inputs |
|
| Keyboard | 3 keys |
| Display | 2 row x 16 character, backlit |
| Z computation formulas |
ISO 12213-2 (AGA8-DC92) ISO 12213-3 (SGERG-88) Z fixed |
| Precision |
According to EN12405 1: Better than 0,5% at reference conditions Better than 1% on the whole operative range |
| Local communication | Optical port IEC 62056-21 (ex IEC 1107) for manufacturer use only |
| Remote communication | 3G Modem SMS, GSM, GPRS (built on ALIMP 8 device) |
| Mechanical class | M2 (in accordance with EN12405-1) |
| Electrical class | E2 (in accordance with EN12405-1) |
|
UE Certification |
MID: 2014/32/UE ATEX: 2014/34/UE EMC: 2014/30/UE |
| Miscellaneous |
Connection to gas quality analyzer or gas chromatograph (only Class 2 version) Firmware updatable both locally and remotely |