FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. Title of the Invention. - "METER TESTING DEVICE"
2. Applicants)

(a) NAME: Reliance Infrastructure Ltd.
(b) NATIONALITY: An Indian Company
(c) ADDRESS: Devidas Lane, Borivali (West), Mumbai- 400 092.
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed:

FIELD OF THE INVENTION
The present invention relates to testing of electricity meters on site. More particularly, the invention pertains to a handheld meter testing device with inbuilt Phantom Load and easy to handle by a single person on sites.
BACKGROUND AND THE PRIOR ART
Dealing with the high consumption complaints of residential customer is an important factor in the Energy Supply and Distribution Sector. While resolution of high consumption complaints on site, convincing the Customer about the correctness of the electricity meter is a difficult task.
Currently, two commonly used methods for electricity meter testing on site are:
• Lamp testing (Manual pulse counting and comparing with calculated pulse for fixed connected lamp load)
• Standard electricity meter Testing - ACCU CHECK (Comparison of consumed energy of meter under test and standard meter connected across consumer load)
Under the Reliance Energy Supply and Distribution area, the numbers of high consumption cases observed for a period of last six months during April 2011 to September 2011 in the Central Division were 7777. Using lamp testing method, 356 out of 7777 cases were registered with repeated visits and again 90 cases required accucheck as lamp testing method is not accurate method.
Also, accucheck has limitations like heavy weight, high cost; require skilled labors for operational requirements.

Hence, the idea of developing electricity meter testing on-site with features like portability, numerical display, and inbuilt load as customer load is not fixed and sometime load is too small so that accurate testing is not possible.
This led to the innovation of the Testing Equipment. The aim of this project is One-Time Resolution of High Consumption customer complaints.
Some prior art and methods are listed below:
Lamp Testing Method
It uses an incandescent bulb as load and the pulses were counted manually for
a fixed time interval and compared with calculated pulses.
Limitations;
Lack of precision during testing and hence accuracy in results varies.
No numerical display of results possible.
Incandescent bulb used as load requires careful handling.
Variation of voltage is not accounted in measurement.
Standard Meter Testing
Standard Meter. Testing devices compares actual energy recorded by meter under test with energy calculated by accucheck using comparison of energy consumed by both. Limitations:
Dependency on customers' connected load as accucheck requires
minimum current.
Complicated testing process, demands skillful work and atleast two
persons.
Test time is about half an hour for a single result
Equipment being bulky needs a four wheeler for transportation
Separate Accucheck meters for testing 1 phase and 3 phase meters.
High cost (in millions)

Class of meter is 0.5%.
US 4646003 describes an apparatus and method for verifying the accuracy of watt-hour meters at their operational site includes applying a phantom load to the meter and to a watt transducer. The relative watt hour readings of the meter are compared to the watt hours computed from the power to the watt transducer and represented as a percentage error of the meter. The phantom load is constituted by a loading transformer with optional load adjustments to take into account different loads to the meter and there are also adjustment means to take into consideration different meter characteristics.
In US 4646003, the meter testing device uses Phantom loading
transformer in the current loop which causes variable current to
circulate resulting in poor thermal stability.
Also the use of Phantom loading transformers on current circuit and
voltage circuit makes the phantom load bulky. Hence the overall
instrument size is large and bulky (not handy).
This bulky structure of Phantom Load indicates that the Phantom load is
not inbuilt.
Current circuit of phantom load is directly looped with current coil of the
reference meter making the reference meter bulky.
Standard meter used is electromechanical meter with restricted accuracy
and not static electric meter.
Use of photo pickup instead of photosensor makes the scanner
attachment complicated and bulky and is also less accurate. And the use
of halogen in the photo pickup can cause rise in temperature.
For error calculations gate control and calculators are used which take
more time as compared to the advanced embedded systems including
microcontrollers. And as a result the overall testing period increases.

Start-Stop hand switch (44) enables the gate controlling circuitry to start and stop of counting, correct instant of Start / Stop of counting may not be possible and will introduce human error.
The above mentioned points make the instrument bulky and less accurate. But the proposed invention discards all this drawbacks by using a reduced size Phantom Load with current transformer (a distinguishing feature) instead of the use of potential transformers (Loading Transformer).
♦ The dimensions of Phantom load thus obtained are 130 X 80 X 25mm {L X B X H). This allows the Phantom Load to be inbuilt since it has less volume.
♦ The important distinguishing feature is that even with this small volume it can circulate the current of 20 Amp/ 240 volts with deviation of lAmp at thermal stability of ldegree Celsius temperature rise.
♦ Hence, the size and volume of the phantom load allows it to be inbuilt thus making the instrument a handheld instrument with overall dimensions 238 X 132 X 43mm (L X B X H) and weight about 2kg such that a single person can handle it with ease at operational sites.
US 5650717 describes an apparatus for testing a meter in a vehicle or any other location where utility power is not available. The apparatus generally includes a stationary fixture and an instrumentation unit. The stationary fixture includes a meter box and power source configured to provide an a.c voltage at the meter box. The stationary fixture further includes a leveling mechanism for mounting and leveling the meter box.
In US 5650717, the electricity meter testing provides power supply at
stationary, fixtures where power supply is not available.
It does not emphasize on the technique of meter testing. Instead, it
simply focuses on the additional provision i.e. power supply.
It is common practice of including power supply with meter testing
instrument in single apparatus but including a load with meter testing

instrument (proposed invention) is a difficult task and hence a distinguishing feature.
US20030025493 describes a solid-state electricity meter uses a sensor to measure a current supplied to a load. In one aspect, the electricity meter housing includes a meter base, a register cover, and a meter cover. The meter base includes a plurality of meter cover lock notches disposed about a periphery of the meter base. However, the meter described in this prior art does not test the accuracy of electricity meter and has no optical sensor.
US20030038621 describes a watthour meter testing device for testing watthour meters is provided that includes a measuring device, a switch, a transmitter and a receiver. The measuring device is in communication with the power measured by the watthour meter. The switch is operable to test electromechanical watthour meters in a first position and operable to test electronic watthour meters in a second position.
The present inventors used an inbuilt Phantom load which is to be connected across the CC of the meter under test instead of customer load. The principle working is based on logical comparison between the number of pulses obtained at the output of pulse counter and the number of pulses given by the standard meter.
OBJECTS OF THE INVENTION
One object of the proposed invention is to overcome the disadvantages / drawbacks of the prior art.
A basic object of the present invention is to provide a system with early revenue realization by resolving the consumer complaint in minimum time and

consumer satisfaction thereby improvement in Brand Image of the organization.
Another object of the present invention is to provide a device which reduce the multiple visits of the field staff.
Yet another object of the present invention is to resolve consumer's Energy Meter related complaints in minimum time on site.
These and other advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.
According to one of the aspect of the present invention there is provided a device for meter testing, said device comprising:
at least one optical sensor connected with a meter to be tested; a pulse counter connected with said optical sensor; a controller means having a comparator means connected with said pulse counter; a standard meter pulse means connected with said controller means providing standard meter pulses to said controller means; a meter constant means; an inbuilt phantom load connected

with CC of the said meter; a display means operatively connected with said
controller means;
wherein said sensor sensing the pulse of the meter provides input pulses to
said pulse counter which in turn feeds the pulses to said controller means
along with standard meter pulses;
wherein said comparator means compares both the pulses and displays the
error percentage on said display means.
Another aspect of the present invention there is provided a method for meter testing, said method comprising steps of: an inbuilt Phantom load being connected across a CC of a meter to be tested, sensing LED pulses of said meter by an optical sensor, determining said LED pulses of said meter by a pulse counter, comparing the said pulses with a standard meter pulses by a comparator and displaying the error percentage on a display means.
Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.
BRIEF DESCRIPTION OF THE FIGURES
The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:
Figure 1 illustrates the block diagram of the meter testing device.
Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be

exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
DETAILED DESCRIPTION OF THE INVENTION
According to one of the embodiment of the present invention there is provided a device for meter testing. The device comprises an optical sensor operatively connected with the meter to be tested, a pulse counter operatively connected with the optical sensor, a controller means having a comparator means operatively connected with the pulse counter , a standard meter pulse means operatively connected with the controller means providing standard meter pulses to the controller means for load current sampling , ammeter constant means, an inbuilt phantom load connected with CC of the meter under test providing it to be hand held device and a display means operatively connected with the controller means.
The LED of said meter starts blinking and the pulses are sensed by the sensor and the counter counts the pulses and said pulses are provided as input to the controller means with standard meter pulses. Both the pulses are compared by the comparator means and displayed along with the error percentage on said display means. The comparator means used in the present invention is a micro-controller based one.
The LED of meter under test starts blinking and the pulses are sensed by the sensor. The counter counts the pulses and the pulses are provided as input to the controller means with standard meter pulses. The comparator means compares both pulses and displays the error percentage on the display means.

The controller means is operatively connected with a meter constant means. The meter constant means selected externally is given as reference the comparator means.
In another embodiment of the present invention there is provided a method for meter testing. The method for meter testing comprising: an inbuilt Phantom load being connected across a CC of a meter to be tested, sensing LED pulses of said meter by an optical sensor, determining said LED pulses of said meter by a pulse counter, comparing the said pulses with a standard meter pulses by a comparator and displaying the error percentage on a display means
The metering device also comprises a metal casing enclosing all the components of the meter testing device. The metal casing is 150 X 150 X 70mm.
The device further comprises a Bakelite casing enclosing the metal casing. The Bakelite casing is of size 220 X 112 X 51mm adapted to make it a handheld device and also detachable connections.
Further comprises a plastic casing enclosing the Bakelite casing is provided to enhance the device exterior appearance and endurance.
The device has an accuracy standardized to 0,2 class with current stability of 1A deviation.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWING
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are

to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
It is to be understood that the singular forms "a," "an,9 and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.
By the term "substantially" it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.
Figure 1 illustrates the present metering device as developed by enclosing the components in a metal casing of 150 X 150 X 70mm which had 94% less volume compared to the prior art meters. It also had hanging wires for connection.

The second stage of development involved reduced size of 220 X 112 X 51mm using a bakelite casing, thus making it a handheld device and also detachable connections.
The final stage, an ABS (plastic) casing was used to enhance the device exterior appearance and endurance.
The electricity meter testing device is used to resolve high consumption complaints at operational sites. Testing begins with disconnecting the customer load and connecting the inbuilt Phantom load across the CC of the meter under test. The meter LED on it starts blinking. These pulses are sensed using optical sensor (5). A pulse counter (1) counts these optical pulses. This count (INI) is given to the comparator (2) as one of the input and standard meter pulse (IN3) as the second input for accuracy calculation. Standard meter (3) uses Current Transducer for load current sampling. The meter constant selected externally is also given as reference (IN2) to the comparator (2).
The comparator logically compares both pulses i.e. meter under test and inbuilt reference standard meter arid displays the error in percentage.
The main feature is use of an inbuilt phantom load (4) in the proposed meter. This is different from the onsite testing instruments available in the market because they depend on the customer load as customer load is not fixed and varying with time. Inbuilt load is certified from IDEMI for its current stability.
The inbuilt phantom load makes the instrument a handheld device i.e. reference energy meter and load is packed in single box, thus its size and weight are lesser compared to those in the market without inbuilt load. Accuracy shouts as calibrated from IDEMI is ±0.2%.

The device can be made to work essentially in three Steps. The prearrangements are common for all the three Steps. They are as follows:
The customer load is disconnected and the Phantom load is connected
across the CC (Current Terminal) of the meter under test.
Power supply terminal of the device is connected to the supply.
Proper alignment of the optical scanner has to be done with the help of
vacuum based arrangement so that proper tuning of pulsating LED can
be achieved.
The next step is to select the select constant of meter under test. This is
done by selecting the meter constant for present device reference.
The 3 modes are:
Start the test by pressing Reset button.
The device displays the % error after completing the 250 reference pulses
(time period- 3 min 15 sec)
Features
Compact and sturdy polyamide glass PCB
Membrane keypad for dust proof and water proof operations
Inbuilt memory chip for data storage
Real Time Data available
Computer / computer network communication using RS232 cable
Downloading and printing of data possible
Meter serial no. related data analysis possible
ABS plastic enclosures for overall finishing and robustness of instrument
especially for outdoor purposes.
Accuracy standardized to 0.2 class with current stability of 1A deviation
accredited by IDEMI Lab.
Advantages Compact instrument (238 X 132 X 43 mm).

Light in weight (2 kg).
Handheld device, easy to handle.
Better current stability as required for testing of electricity meters.
Shorter testing time (max 5 min).
Common for both 1 phase and 3phase electricity meters (with looping of
phases).
Economical.

WE CLAIM
1. A device for meter testing, said device comprising:
at least one optical sensor connected with a meter to be tested;
a pulse counter connected with said optical sensor;
a controller means having a comparator means connected with said
pulse counter;
a standard meter pulse means connected with said controller means
providing standard meter pulses to said controller means;
a meter constant means;
an inbuilt phantom load connected with CC of the said meter;
a display means operatively connected with said controller means;
wherein said sensor sensing the pulse of the meter provides input pulses
to said pulse counter which in turn feeds the pulses to said controller
means along with standard meter pulses;
wherein said comparator means compares both the pulses and displays
the error percentage on said display means.
2. The device as claimed in claim 1, wherein said comparator means adapted to logically compare the number of pulses obtained at the output of the pulse counter and the number of pulses given by the standard meter.
3. The device as claimed in claim 1 further comprising a current transducer connected to the standard meter output for load current sampling to be fed into the controller means.
4. The device as claimed in claim 1, wherein said meter constant means
comprising providing a predetermined value for comparison of inputs received
by the controller from the standard meter and the pulse counter.

5. The device as claimed in claim 1 further comprising inbuilt memory chip for data storage.
6. The device as claimed in claim 1, wherein said device optionally connectable to a computer or a group of computers connected in a network.
7. The device as claimed in claim 1, wherein said device is adapted to be used for single phase applications.
8. The device as claimed in claim 7 is optionally adapted to be used for three phase meters using Phase Looping method .
9. The device as claimed in claim 1 further comprising an inbuilt thermal
printer.
10. A method for meter testing by the said device as claimed in claim 1,
wherein said method comprising;
an inbuilt Phantom load being connected across a CC of a meter to be tested,
sensing LED pulses of said meter by an optical sensor, determining said LED pulses of said meter by a pulse counter, comparing the said pulses with a standard meter pulses by a comparator and displaying the error percentage on a display means.
11. The method as claimed in claim 10, wherein said comparator means
logically compares the number of pulses obtained at the output of the pulse
counter and the number of pulses given by the standard meter.

12. The method as claimed in claim 10 further comprising sampling of load currents by means of current transducer connected to the standard meter output for feeding into the controller means.
13. The method as claimed in claim 10, wherein said comparison of inputs received by the controller from the standard meter and the pulse counter is performed with reference to a predetermined value provide by the meter constant means.
14. A device for meter testing substantially as herein described with reference to the accompanying drawings and the description.
15. A method for meter testing substantially as herein described with reference to the accompanying drawings and the description,