Secure Liberty EG4v12 Operating manual

Liberty EG4v12 (G1.6) gas meter
User cum maintenance guide
BGX701-240-R01

Page 2 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
Commercial and Confidential
Copyright © 2019-20, SIHPL. All rights reserved. E&OE.
Liberty EG4v12®is a registered trade name of Secure Meters Ltd.
Other product names are trademarks or registered trade names of their respective owners.
As part of Secure Meters’ continuous endeavours to improve its products, specifications mentioned are liable
to change.
The gas meter is compliant with the following:
Standard(s):
BS EN 1359
Directives:
● Weight & Measure, Legal Metrology, Govt. of India
● WPC
● MID Directive (2014/32/EU)
● ATEX Directive(2014/34/EU)
● ROHS Directive (2011/65/EU)

BGX701-240-R01 Liberty gas EG4v12 user cum maintenance manual Page 3 of 32
Table of Contents
1Introduction .................................................................................................................................... 5
1.1Target audience...............................................................................................................................................................................5
1.2About this manual..........................................................................................................................................................................5
1.3Important safety information....................................................................................................................................................5
1.4Installation, maintenance and environment .......................................................................................................................5
2Product overview and operating principle .................................................................................. 7
3Product description ........................................................................................................................ 8
3.1Liberty EG4v12 main features.....................................................................................................................................................8
3.1.1Electronic unit (EU)......................................................................................................................................................9
3.1.2Battery ..............................................................................................................................................................................9
3.1.3Integral shut-off valve................................................................................................................................................9
3.1.4Tamper detection..........................................................................................................................................................9
3.2Using the display............................................................................................................................................................................9
3.2.1Display icons ................................................................................................................................................................10
3.2.2Keypad functions........................................................................................................................................................10
3.2.3Financial display ..........................................................................................................................................................11
3.2.4Display timing...............................................................................................................................................................11
4Meter specifications .................................................................................................................... 12
4.1General specification .................................................................................................................................................................. 12
4.2Handling, storage and operating conditions..................................................................................................................... 13
4.3Liberty EG4v12 dimensions........................................................................................................................................................ 13
5Functional specification .............................................................................................................. 14
5.1Meter operating modes.............................................................................................................................................................. 14
5.1.1Prepayment mode ...................................................................................................................................................... 14
5.1.2Commissioning mode ............................................................................................................................................... 14
5.2Registers and snapshots............................................................................................................................................................ 15
5.2.1Registers ........................................................................................................................................................................ 15
5.2.2Snapshot logging........................................................................................................................................................ 15
5.3Timekeeping.................................................................................................................................................................................... 16
5.4Accounting....................................................................................................................................................................................... 16
5.4.1Standing charge deduction .................................................................................................................................... 16

Page 4 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
5.4.2Accounting zones in prepayment mode.............................................................................................................17
5.4.3Emergency credit (EC)...............................................................................................................................................18
5.4.4Friendly credit(FC) ...................................................................................................................................................... 19
5.5UTRN transaction.......................................................................................................................................................................... 19
5.6Retain credit ...................................................................................................................................................................................20
5.7Meter configuration and functionality ................................................................................................................................20
5.8Account-based prepay alerts....................................................................................................................................................20
5.9Meter valve state.......................................................................................................................................................................... 21
5.9.1Opening the valve from the ‘READY ‘state....................................................................................................... 21
5.9.2Gas valve connection displays .............................................................................................................................. 21
5.10Detecting events...........................................................................................................................................................................22
5.10.1Hardware events.........................................................................................................................................................22
5.10.2Tamper events .............................................................................................................................................................22
5.10.3Prepayment events....................................................................................................................................................23
5.10.4Valve operation events ............................................................................................................................................23
5.11Communication channels..........................................................................................................................................................23
6Maintenance ................................................................................................................................. 24
6.1Replacing the battery in the Liberty EG4v12 gas meter ................................................................................................24
6.2Replacing Liberty EG4v12 gas meter......................................................................................................................................26
7Working with the mobile app ..................................................................................................... 27
7.1Logging-in........................................................................................................................................................................................ 27
7.2Connecting the device ................................................................................................................................................................28
7.3Recharge options..........................................................................................................................................................................28
7.3.1Purchasing a token (Online)...................................................................................................................................28
7.3.2Saving a purchased token.......................................................................................................................................29
7.3.3Applying a pending token .......................................................................................................................................29
8Glossary ........................................................................................................................................ 30
9Notes ............................................................................................................................................. 31

BGX701-240-R01 Liberty gas EG4v12 user cum maintenance manual Page 5 of 32
1 Introduction
1.1 Target audience
This document is intended for technical users, utilities and fully qualified, registered installers of Liberty
EG4v12 meters.
1.2 About this manual
The manual describes functions and features of the Liberty EG4v12 meter and provides necessary information
needed to use the meter.
1.3 Important safety information
Attention is drawn as follows in the individual chapters of this user manual with classified word symbols
and pictographs to the relevant danger level, i.e. the severity and probability of any danger:
Definition of danger
This symbol is used to indicate a possibly dangerous situation which could
result in severe physical injury or a fatality.
Definition of warning
This symbol is used to indicate a possibly dangerous situation which could
result in minor physical injury or material damage.
The meter should only be installed by trained personnel safely and securely in accordance with local best
practices.
1.4 Installation, maintenance and environment
 The product should be installed in line with PNGRB guidelines. Install in a location where it is
protected from impact and friction.
 A visual inspection should be performed before installing the meter. The following should be
checked, as a minimum:
o No evidence of external damage or missing parts
● The product conforms to ATEX zone 2 requirements. ATEX code is
II 3 G Ex ic nA IIA T6
 There is no maintenance, repair or adjustment intended for this meter. There are no interchangeable
or serviceable parts (except primary battery which can be exchanged in service by authorised
personnel only), without breaking metrology seal.
Attention
Danger

Page 6 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
 The primary battery in the meter can be replaced by authorised personnel, when in service. However,
this battery must only be supplied by Secure Meters Ltd.
 You may contact the sales team representative at Secure Meters Limited for further information.
 When replacing the gas meter battery, ensure that you follow appropriate Electrostatic discharge
(ESD) procedures before you open the meter cover. This will eliminate risk or possible damage to the
meter circuit. A few methods are mentioned below:
o Wear or use well-grounded ESD protective gear such as a wrist strap or pad during the
operation.
o Wear anti-static ‘Finger cots’ before you touch the meter cover.
o Touch the Inlet/Outlet port of the Gas meter or any earthed metallic surface to discharge
static electricity before you touch the meter cover.
Observe local safety norms when disposing of the product and any batteries that it
contains, at the end of their life, to ensure that they do not enter the household
waste stream.
The meters will be sent to an approved dealer for secure disposal.
 The product surfaces can be cleaned/wiped only with a damp or anti-static cloth.

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2 Product overview and operating principle
Liberty EG4v12 supports Prepayment mode of operation. The meter is based on a positive displacement
principle. It has a well-defined measurement compartment that alternately fill and empty when gas is
consumed. By knowing the volume displaced in each cycle and by applying proper gear ratio, the meter will
read the gas consumption in cubic meters.
Figure 1: Operating scenario
The meter has a Bluetooth interface (BLE 4.2) for communication with the mobile app and a user interface
comprising of a custom LCD and 12-key keypad. The user interface provides a means of manually entering
prepayment Unique Transaction Reference Numbers (UTRNs). UTRNs can also be entered via mobile app over
Bluetooth.
Commands or configuration changes can be delivered to the meter in the form of UTRNs (recharge tokens).
UTRNs are encrypted codes and are valid only for the meter for which they are generated.
The whole communication (token entry and data reading) between the mobile app and meter over the
Bluetooth takes between one to three minutes depending on location. The data read from the meter is
transferred to the meter data server of Secure at the backend whenever data (internet) connection is
available in the mobile. For sending data to the backend, the mobile app should be open in view mode.
The meter has an integral shut-off valve (SOV) that enables or prevents the flow of gas. The integral shut-off
valve is NOT a safety valve.
The electronic unit (EU) is powered by a long-life non-rechargeable lithium battery which also powers the
unit’s internal clock.
Note:
Communication with the meter over BLE is restricted from 10* pm to 7* am.
* This information is subjected to change

Page 8 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
3 Product description
3.1 Liberty EG4v12 main features
Figure 2: Liberty EG4v12 meter
The integrity of the meter seals should be checked periodically.
LCD information window (Display)
Liberty EG4v12 has a backlit, monochrome LCD for displaying metering data, alerts and other relevant
information. The meter is battery-powered, and therefore the display is enabled only on demand (key press).
The meter display will return to ‘sleep mode’ if there is no user interaction after approximately 30 seconds.
Keypad
The keypad has ten 0-9 numeric keys and two special keys marked ‘A’ (blue) and ‘B’ (red). Key ‘5’ has a raised
dot to help visually impaired users to navigate.
The EU front cover
The EU front cover has a transparent window to view the display and a flange to protect it from dust and
moisture ingress. The cover is secured to the meter base with two sealable M4 machine screws, on either
Direction of flow of gas

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side, at the front. Provision is also made for front/battery cover ‘open’ detection. Removal of the cover and
access to the battery compartment requires breaking the plastic seals and undoing the screws.
3.1.1 Electronic unit (EU)
The electronic unit (EU) is fitted on the front of the mechanical gas meter using mounting studs. The
enclosure has an ingress rating of IP-54. The EU houses the processor and battery.
Figure 3: Electronic unit with the cover removed
Functions of the EU
● Computes the volume of gas passed through the gas meter, processes and stores the information in
its memory and communicates the information to mobile app over Bluetooth (on request).
● Carries out all accounting and billing activities for gas consumption
● Detects and records flags of tamper events/faults
● Monitors battery voltage for detection of low battery condition
The EU generates a ‘low battery’ alert when the battery voltage is continuously below 3.3 volts for 48
hours. In the case of battery failure, the EU will close the gas meter valve, stop metrology and all
communications as well as take backups of all registers.
3.1.2 Battery
A 3.6 V D-Cell battery provides power to the EU. The battery is fitted in a small compartment inside the EU
and has an independent cover with cover removal detection and a tamper-evident sealing arrangement.
Under normal operating conditions, the battery is expected to last for approx ten years. The hardware and
firmware in the EU is designed to work with low power consumption to conserve battery life.
3.1.3 Integral shut-off valve
The meter has an integrated supply shut-off valve mounted inside the metal meter enclosure. The EU can be
factory configured to close the valve when it detects any of the following events:
a) Battery cover open detection
b) Magnet tamper detection
c) Tilt detection
3.1.4 Tamper detection
The meter has anti-tamper features including tilt sensor, magnetic tamper sensor and battery cover open
sensor.
3.2 Using the display
The figure below shows the illuminated segments during display test when key 0 is pressed:
EU front cover/battery open sensor
Replaceable battery
Self-tapping screws
Metrology seal
Self-tapping screws
Mounting studs

Page 10 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
Figure 4: Meter display in ‘Test Mode’
Note:
Only a few icons as described in section 3.2.1 are applicable for Liberty EG4v12 gas meter.
The meter is programmed to display information on manually pressing any numeric key on the meter
keypad. Sets of information relating to a function are grouped on each numeric key. Repeated pressing of
the same key manually jumps the display through the configured display list. Pressing key ‘B’ manually
allows the displays to go backwards.
3.2.1 Display icons
The following table lists the icons displayed on the meter LCD and their significance:
Display icon Significance
Displays alpha-numeric data such as gas consumption or a UTRN token
number during token entry or an alert message.
Indicates the volume of gas
Indicates the supply status – ON, READY, OFF
Table 1: Interpretation of LCD icons
3.2.2 Keypad functions
Number keys (0-9) functions:
 Used to display meter data
 Used to input tokens.
Key ‘A’ functions:
 Initiates token entry;
 Used as backspace during
token entry;
 Used to enable Emergency
Credit when made available;
 Initiates supply reconnection
from ARM state.
Key ‘B’ functions:
 Used to scroll back through a
display sequence;
 Initiates token authentication
process;
 Used to confirm supply
reconnection from ARM state.
Key ‘0’ functions:
 Initiates Commissioning
process if applicable.
 Displays test mode, time
and date (after successful
commissioning)
Balance, Volume and Days left
Emergency credit value and status
Friendly credit status

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3.2.3 Financial display
All financial information will be displayed in Rupees and Paisa. Most numerical displays use the decimal
points predefined in the display graphics, as shown below:
3.2.4 Display timing
Display timings are preconfigured for each data item in a display sequence with each item being preceded
by a relevant title. A title is displayed for two (2) seconds, followed by the data for four (4) seconds followed
by the next set of information.

Page 12 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
4 Meter specifications
4.1 General specification
Specification Description
Mechanical
Weight (in kg) Approx. 2.5 kg
Case work Pressed steel
Finish Powder coating
Diaphragms Synthetic
Shut off valve Internal electrically operated, operational life 2000 cycles
(2000 On and 2000 Off operations)
Sealing provisions Two sealable battery cover screws
Index English
Max index reading 99999.999 m3
Gas connections 3/4” BS 746
Keypad Silicon material
Display
LCD with backlight, ten starburst character (7mm high)
with icons.
Viewing angle
180to 200at 12 o’clock and 6 o’clock
250at 3 o’clock and 9 o’clock from normal to window
Compliance
Metrology BS EN 1359
Fire resistant EN1359 (pressed steel version)
Metrology
Cyclic volume 1.2dm3(Liberty EG4v12)
Flow
range
Qmax 2.5 m3/hr
Qmin 0.016 m3/hr
Starting flow rate 3.0 dm3/hr
Maximum working
pressure (Pmax) 0.5 bar
Gas type Natural
Environmental
Operating temperature
(Tmin to Tmax) - 10 °C to + 55 °C
Storage temperature - 25°C to + 60 °C
Ingress protection IP54 (EN60529)

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4.2 Handling, storage and operating conditions
Liberty EG4v12 meter is an electro-magnetic device containing delicate components and should be handled
carefully during transit, storage and installation to ensure accuracy and endurance. The meter should be
stored upright with inlet and outlet boss dust caps in place and protected from physical vibration and
shocks. Wherever possible the meter should be kept in its original packaging on a shelf or pallet until it is
installed at the customer’s site.
Proper installation and removal procedures should be followed to prevent damage or injury. Physical damage
to the meter’s case could indicate damage to internal components. Under no circumstances should an
attempt be made to install a damaged meter.
Ideally, the meter should be stored and operated in a dry, well ventilated, climate-controlled building. Rapid
changes in temperature and humidity should be avoided.
4.3 Liberty EG4v12 dimensions
The following diagram shows the outer dimensions of the Liberty EG4v12. All dimensions are in millimetres
(mm):
Figure 5: Liberty EG4v12 front and side views

Page 14 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
5 Functional specification
The following functional features of Liberty EG4v12 are described in this section:
1. Meter operating modes
2. Registers and snapshots
3. Time keeping
4. Accounting
5. UTRN Transaction
6. Meter configuration and functionality
7. Meter valve state
8. Detecting and logging events
9. Communication channels
10. Meter reading data
11. Engineering Codes
5.1 Meter operating modes
Liberty EG4v12 meter operates in pre-payment mode. Also, there is a commissioning mode for commissioning
of the meter.
5.1.1 Prepayment mode
In Prepayment mode, the meter will perform billing actions as detailed in ’Device information
Device information consists of the meter serial number, meter program name, commodity type and the
meter type.
Billing snapshot’ in Section 5.2.2.1. Prepayment mode supports four different accounting zones as detailed in
Section 5.4.2 ‘Accounting zones in prepayment mode’ and generates account-specific visual alerts. Also, this
mode supports the following features:
● Adding an absolute value to the meter’s account through meter keypad or mobile app
● Displaying account-specific messages
● Emergency Credit and Friendly Credit support
● Meter valve operation based on the account state, Friendly Credit and Emergency Credit
configurations.
● Retain credit
The meter activates the following functionality when operating in this mode:
● Slab or Block tariff
● Events and tamper detection
● Prepayment features:
o Sending visual alerts on display when meter credit becomes low
o Updating, activating and repaying of Emergency Credit
o Disconnecting and reconnecting supply
5.1.2 Commissioning mode
After physically installing the meter, the commissioning process is carried out. This process is initiated by
the gas meter when it is put into commissioning mode (by pressing key ‘0’). If carried out correctly, the

BGX701-240-R01 Liberty gas EG4v12 user cum maintenance manual Page 15 of 32
entire commissioning process, including the gas test but excluding gas meter installation, should take less
than ten (10) minutes.
Note: Once the commissioning is carried out successfully, standing charge deduction becomes applicable.
5.2 Registers and snapshots
5.2.1 Registers
The gas meter EU records the volume of gas consumed in m3.
Measurement and recording of the gas flow
The gas meter EU is designed to receive pulses from its gas meter. Each pulse indicates the quantity of gas
flow.
5.2.2 Snapshot logging
The gas meter EU logs the following three types of data which will be sent to the mobile app on the receipt
of a snapshot request:
a) Device information
b) Billing snapshot
c) Current snapshot
The snapshot data consists of the following details as per configuration:
● Cumulative volume (resolution is 1 litre)
● Prepayment information consisting of currency code, meter account balance, cost of consumption
and standing charges deducted.
Note:
Cumulative volume and standing charges are not shown on the mobile app.
5.2.2.1 Device information
Device information consists of the meter serial number, meter program name, commodity type and the
meter type.
5.2.2.2 Billing snapshot
Meter will log the billing data of cumulative volume consumed during billing period, cost of consumption,
deducted standing charges and billing flags.
The meter will take a snapshot of its energy registers for billing purpose due to any of the following actions:
● Scheduled billing date
● The occurrence of an abnormal event, for example, corruption of energy register or rollover of
consumption amount
The meter stores a total of 3 billing snapshot. Billing snapshot data is updated on a FIFO basis.
5.2.2.3 Current snapshot
The meter will send the present value of its gas volume, meter balance, emergency credit limit, bill amount
since the last billing, average cost/day, days left, cost of the previous day, cost of last seven days’
consumption and diagnostic flags.

Page 16 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
5.3 Timekeeping
The gas meter clock maintains time in hour, minutes, and seconds format.
All data logging (e.g. events data and snapshots) and scheduled task activation (e.g. rate register switching,
Friendly Credit timing, minimum charge deduction, etc.) takes place using the country’s standard time.
When the time is invalid for any reasons, an RTC failure flag is logged. The date and time on the meter
display will appear as ‘--------’
5.4 Accounting
This section describes the accounting features in the Liberty EG4v12 meter.
5.4.1 Standing charge deduction
Liberty EG4v12 meter can be configured at the factory end to deduct a specified amount of standing charge
from its current account and Emergency Credit account (if applicable); this deduction takes place in one of
the following two ways:
1. Daily
2. At the end of the billing period (monthly/bimonthly/quarterly)
5.4.1.1 Daily
When configured as ‘daily’, the standing charges are deducted every day at midnight.
Example 1,
Consumption = Rs10
Standing charge = Rs6
Deduction at midnight = Rs6 besides the consumption
Example 2,
Consumption = Rs0
Standing charge = Rs6
Total deduction at midnight = Rs6
5.4.1.2 At the end of the billing period
When configured as ‘at the end of billing period’, the standing charges are deducted at bill end
(monthly/bimonthly/quarterly). The following cases are possible:
If the consumption amount within the billing period is more than the standing charge for that billing period,
no amount is deducted besides the consumption.
For example,
Consumption = Rs150
Standing charge = Rs100
No amount is deducted at the end of the billing period in addition to the consumption.
If the consumption amount within the billing period is less than the standing charge for that billing period,
the difference amount is deducted besides the consumption.

BGX701-240-R01 Liberty gas EG4v12 user cum maintenance manual Page 17 of 32
For example,
Consumption = Rs20
Standing charge = Rs100
Rs100- Rs20 = Rs80 will be deducted at the end of billing period in addition to the consumption.
Notes:
● It is possible for the account balance to go in negative after deduction of standing charges.
● The deduction takes place irrespective of the volume of gas consumed or the meter’s account status.
● To stop the deduction of standing charges in the meter, a Retain credit transaction needs to be
performed.
5.4.2 Accounting zones in prepayment mode
Liberty EG4v12 meters operating in Prepayment mode will have the following four accounting zones:
● Credit zone
● Low credit zone
● Emergency credit zone
● No credit zone
Figure 6: Liberty EG4v12 accounting zones in prepayment mode
In Prepayment mode, the meter maintains two internal accounts: the main account and the emergency
credit account. Minimum charges are deducted at billing date.
Each time the meter account passes through a credit zone threshold, it generates a visual alert.
‘Low credit’ threshold and ‘Low emergency credit’ threshold values can be configured during manufacturing.
In Prepayment mode the meter will provide the following information on Emergency Credit:
a) When emergency credit is available for selection
b) When emergency credit is in use
c) When emergency credit has been fully used

Page 18 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
5.4.2.1 Credit zone
In the credit zone, the value of the meters’ account, after a reduction, is checked against the meter’s Low
Credit threshold. No action is taken if the value is above the threshold. When the value goes below the
threshold, the meter generates an alert.
5.4.2.2 Low credit zone
In the low credit zone, the value of the meter account, after a reduction, is checked against the meter’s cut-
off threshold. No action is taken if the value is above the cut-off threshold. In this zone, emergency credit is
made available to the user before the value reaches the cut-off threshold. A visual indicator on the meter’s
display indicates that emergency credit is available. While the meter is operating in this zone, if
emergency credit (Refer section 5.4.3 for details )is made available, the user can enable it by pressing
key ‘A’ on the meter’s keypad to prevent supply disconnection when the meter reaches the cut-off
threshold.
5.4.2.3 Emergency credit zone
In the emergency credit zone, the value of the meter account, after a reduction, is checked against the
meter’s low emergency credit threshold. No action is taken if the value is above the threshold. A visual
indicator on the meter display will indicate when emergency credit is in use. Also, the meter provides
information on the emergency Credit amount remaining.
If the entire emergency credit allowance is used up, but the meter is operating in friendly credit (Refer
section 5.4.4 for details) period, the supply will remain ‘On’ till friendly credit ends. The user must add
sufficient credit to put the meter’s account into positive balance before supply restoration is permitted.
5.4.2.4 No credit zone
In the no credit zone, there is no emergency credit left to be used by the user. Therefore, the supply will
remain disconnected until the user tops up the meter’s account sufficiently to the amount which is shown
as –ve balance on the meter.
5.4.3 Emergency credit (EC)
Liberty EG4v12 operating in Prepayment mode supports Emergency Credit functionality which if enabled will
prevent immediate supply disconnection when the meter account becomes zero or negative. Emergency
Credit is made available to users when their meter account passes the Low Credit threshold. A visual
indication on the meter’s display will indicate the availability of Emergency Credit. It can be enabled by
pressing key ‘A’ on the meter keypad. If Emergency Credit is available but ignored by the user previously,
then it can again be availed by pressing key 7 on the meter keypad.
‘Not now’, ‘Selected’, ‘In use’ or ‘Used up’ display will appear on the meter as per the current EC status.

BGX701-240-R01 Liberty gas EG4v12 user cum maintenance manual Page 19 of 32
Users can also enable Emergency Credit (if not already exhausted) after supply disconnection by pressing
Key 7. If the meter is running in EC, the mobile app will show account status as follows:
IF EC is not availed, the mobile app will show ‘low money’.
5.4.4 Friendly credit(FC)
Friendly Credit is a factory configurable non-disconnection period which prevents account-related supply
disconnection at certain times of the day, days of the week or on defined dates in the year such as public
holidays.
In a Friendly Credit period if the meter’s account balance becomes zero and Emergency Credit is not enabled
or is used up then the supply will not disconnect because a grace period of x minutes is configured at the
end of Friendly Credit period which interrupts supply disconnection.
Pressing key 8 on the meter keypad displays the current status of FC and the time at which it ends or starts
depending upon its current state.
5.5 UTRN transaction
A Unique Transaction Reference Number is an encrypted code used for adding money to the meter’s account.
UTRNs can be uploaded to the meter from a mobile app or entered using the meter’s keypad.
Account’s current
status
Account’s current
balance
Figure 7: Account status on mobile app

Page 20 of 32 Liberty gas EG4v12 user cum maintenance manual BGX701-240-R01
The meter will reject UTRNs if they fail authentication (for example, UTRN is not for this meter, duplicate,
etc.) and are invalid. Each time a UTRN is rejected, the meter displays a failure message along with a failure
reason.
When entering a UTRN via the meter’s keypad, there is a timeout period of 20 seconds after which time, if no
key has been pressed the meter will begin automatic authentication of the UTRN.
The meter allows five (5) successive incorrect UTRN entries (via keypad) after which it locks key ‘A’ (key ‘A’ is
used for initiating UTRN entry) for 30 seconds with a ‘Keypad Locked’ message on its display. After that, the
lock period doubles with each incorrect UTRN until the 10th attempt is reached when the lock period is 16
minutes. Acceptance of a correct UTRN resets the incorrect UTRN counter and the lock period to zero and
takes necessary action based on the UTRN type.
In case, the tokens are sent from the mobile app:
If seven transactions are already performed in the last 30 minutes, the app blocks the user for the next 15
minutes.
5.6 Retain credit
This transaction is performed to stop the deduction of standing charges in the meter when you are not
consuming the gas for a longer duration.
A retain credit token of less than or equal to ten rupees is generated from the vending station. This token is
entered into the meter and a refund code is generated for the remaining balance. This token stops the
deduction of standing charges in the meter. Once a new recharge token is entered, the meter starts
deducting the standing charges normally.
5.7 Meter configuration and functionality
The EU verifies and authenticates the commands it receives before executing them. If authentication fails,
the meter will reject the command.
The following parameters are configurable in field Liberty EG4v12 meters via authenticated UTRNs (‘Vend +
tariff’ type):
● Tariff rates and slabs
● Standing charge
● Credit addition (recharge through vend)
5.8 Account-based prepay alerts
Liberty EG4v12 meters operating in prepayment mode displays visual alerts (see Figure 6 ) under the
following circumstances based on the state of its account:
● ‘Low credit’ alert if the credit level in the meter’s account reaches or passes below the configured
low credit threshold.
● ‘Emergency credit available’ alert if the credit level in the meter’s account reaches or passes below
the configured emergency credit threshold, thereby making the users aware of the availability of
Emergency Credit.
● ‘No credit’ alert if the credit level in the meter’s account reaches or passes below zero credit
threshold.